kmpdfkit_demo/Demo/Examples/PDFViewer/MainPage.xaml.cs

using ComPDFKit.PDFDocument;
using ComPDFKit.PDFPage;
using Compdfkit_Tools.Data;
using Compdfkit_Tools.Edit;
using Compdfkit_Tools.Helper;
using Compdfkit_Tools.PDFControl;
using ComPDFKitViewer;
using ComPDFKitViewer.AnnotEvent;
using ComPDFKitViewer.PdfViewer;
using Microsoft.Win32;
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using Path = System.IO.Path;

namespace PDFViewer
{
    public partial class MainPage : UserControl, INotifyPropertyChanged
    {
        #region Property
        private bool isFirstLoad = true;
        private string currentMode = "Viewer";
        private PDFViewControl passwordViewer;
        private PDFViewControl pdfViewControl = new PDFViewControl();
        private CPDFAnnotationControl pdfAnnotationControl = null;
        private UIElement pdfEditControl = null;
        private CPDFPageEditControl pageEditControl = null;
        private FromPropertyControl pdfFormControl = new FromPropertyControl();
        private PDFImageEditControl imageEditControl = null;
        private CPDFDisplaySettingsControl displayPanel = null;

        private double[] zoomLevelList = { 1f, 8f, 12f, 25, 33f, 50, 66f, 75, 100, 125, 150, 200, 300, 400, 600, 800, 1000 };
        public bool CanSave
        {
            get
            {
                if (pdfViewControl != null && pdfViewControl.PDFView != null)
                {
                    return pdfViewControl.PDFView.UndoManager.CanSave;
                }
                return false;
            }
        }

        public bool CanUndo
        {
            get
            {
                if (pdfViewControl != null && pdfViewControl.PDFView != null)
                {
                    return pdfViewControl.PDFView.UndoManager.CanUndo;
                }
                return false;
            }
        }

        public bool CanRedo
        {
            get
            {
                if (pdfViewControl != null && pdfViewControl.PDFView != null)
                {
                    return pdfViewControl.PDFView.UndoManager.CanRedo;
                }
                return false;
            }
        }

        private PDFEditEvent lastPDFEditEvent = null;
        public event Func<string[], bool> CheckExistBeforeOpenFileEvent;
        public event PropertyChangedEventHandler PropertyChanged;
        public event EventHandler FileChangeEvent;
        #endregion

        public MainPage()
        {
            InitializeComponent();
            DataContext = this;
            if (pdfFormControl != null)
            {
                pdfFormControl = new FromPropertyControl();
            }
        }

        #region Initial Load Unload

        public void InitialPDFViewControl(PDFViewControl newPDFViewer)
        {
            pdfAnnotationControl.SetPDFViewer(newPDFViewer.PDFView);
            FormBarControl.InitWithPDFViewer(newPDFViewer.PDFView, pdfFormControl);
            pdfFormControl.SetPDFViewer(newPDFViewer.PDFView);
            pdfAnnotationControl.AnnotationCancel();
            AnnotationBarControl.ClearAllToolState();
            ExpandRightPropertyPanel(null, Visibility.Collapsed);
            newPDFViewer.PDFView.WidgetClickHandler += PDFView_WidgetClickHandler;
            newPDFViewer.CustomSignHandle = true;
        }

        private void UserControl_Loaded(object sender, RoutedEventArgs e)
        {
            pdfAnnotationControl = new CPDFAnnotationControl();
            BotaSideTool.AddBOTAContent(BOTATools.Thumbnail | BOTATools.Outline | BOTATools.Bookmark | BOTATools.Search | BOTATools.Annotation);
            LoadDocument();
        }

        public void SetPDFViewer(PDFViewControl newPdfViewer)
        {

            if (newPdfViewer != null)
            {
                pdfViewControl = newPdfViewer;
            }

        }

        private void CPDFTitleBarControl_Loaded(object sender, RoutedEventArgs e)
        {
            CPDFTitleBarControl.OpenFileEvent -= CPDFTitleBarControl_OpenFileEvent;
            CPDFTitleBarControl.OpenFileEvent += CPDFTitleBarControl_OpenFileEvent;

            CPDFTitleBarControl.SaveAsFileEvent -= CPDFTitleBarControl_SaveAsFileEvent;
            CPDFTitleBarControl.SaveAsFileEvent += CPDFTitleBarControl_SaveAsFileEvent;

            CPDFTitleBarControl.SaveFileEvent -= CPDFTitleBarControl_SaveFileEvent;
            CPDFTitleBarControl.SaveFileEvent += CPDFTitleBarControl_SaveFileEvent; ;
        }

        private void AnnotationBarControl_Unloaded(object sender, RoutedEventArgs e)
        {
            AnnotationBarControl.AnnotationPropertyChanged -= AnnotationBarControl_AnnotationPropertyChanged;
            AnnotationBarControl.AnnotationCancel -= AnnotationBarControl_AnnotationCancel;
        }

        private void AnnotationBarControl_Loaded(object sender, RoutedEventArgs e)
        {
            CPDFAnnotationType[] annotationProperties = { CPDFAnnotationType.Highlight, CPDFAnnotationType.Underline, CPDFAnnotationType.Strikeout, CPDFAnnotationType.Squiggly, CPDFAnnotationType.Freehand, CPDFAnnotationType.FreeText, CPDFAnnotationType.Note, CPDFAnnotationType.Circle, CPDFAnnotationType.Square, CPDFAnnotationType.Arrow, CPDFAnnotationType.Line, CPDFAnnotationType.Image, CPDFAnnotationType.Stamp, CPDFAnnotationType.Signature, CPDFAnnotationType.Link, CPDFAnnotationType.Audio };

            AnnotationBarControl.InitAnnotationBar(annotationProperties);
            AnnotationBarControl.AnnotationPropertyChanged += AnnotationBarControl_AnnotationPropertyChanged;
            AnnotationBarControl.AnnotationCancel += AnnotationBarControl_AnnotationCancel;
        }
        #endregion

        #region  UI 
        /// <summary>
        /// InfoChanged
        /// When the PDF zoom ratio changes, the value of the zoom control also changes.
        /// </summary>
        private void PdfViewer_InfoChanged(object sender, KeyValuePair<string, object> e)
        {
            if (e.Key == "Zoom")
            {
                CPDFSaclingControl.SetZoomTextBoxText(string.Format("{0}", (int)((double)e.Value * 100)));
            }
        }

        private void EditLink_Click(object sender, RoutedEventArgs e)
        {
            RightPanelButton.IsChecked = true;
            PropertyContainer.Visibility = Visibility.Visible;
        }

        private double CheckZoomLevel(double zoom, bool IsGrowth)
        {
            double standardZoom = 100;
            if (zoom <= 0.01)
            {
                return 0.01;
            }
            if (zoom >= 10)
            {
                return 10;
            }

            zoom *= 100;
            for (int i = 0; i < zoomLevelList.Length - 1; i++)
            {
                if (zoom > zoomLevelList[i] && zoom <= zoomLevelList[i + 1] && IsGrowth)
                {
                    standardZoom = zoomLevelList[i + 1];
                    break;
                }
                if (zoom >= zoomLevelList[i] && zoom < zoomLevelList[i + 1] && !IsGrowth)
                {
                    standardZoom = zoomLevelList[i];
                    break;
                }
            }
            return standardZoom / 100;
        }

        private void PDFView_AnnotEditHandler(object sender, List<ComPDFKitViewer.AnnotEvent.AnnotEditEvent> e)
        {
            BotaSideTool.LoadAnnotationList();
        }

        private void UndoManager_PropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            OnPropertyChanged(e.PropertyName);
        }

        private void PasswordUI_Closed(object sender, EventArgs e)
        {
            PopupBorder.Visibility = Visibility.Collapsed;
            PasswordUI.Visibility = Visibility.Collapsed;
        }

        private void PasswordUI_Canceled(object sender, EventArgs e)
        {
            PopupBorder.Visibility = Visibility.Collapsed;
            PasswordUI.Visibility = Visibility.Collapsed;
        }

        private void PasswordUI_Confirmed(object sender, string e)
        {
            if (passwordViewer != null && passwordViewer.PDFView != null && passwordViewer.PDFView.Document != null)
            {
                passwordViewer.PDFView.Document.UnlockWithPassword(e);
                if (passwordViewer.PDFView.Document.IsLocked == false)
                {
                    PasswordUI.SetShowError("", Visibility.Collapsed);
                    PasswordUI.ClearPassword();
                    PasswordUI.Visibility = Visibility.Collapsed;
                    PopupBorder.Visibility = Visibility.Collapsed;
                    pdfViewControl = passwordViewer;
                    LoadDocument();
                    FileChangeEvent?.Invoke(null, EventArgs.Empty);
                }
                else
                {
                    PasswordUI.SetShowError("error", Visibility.Visible);
                }
            }
        }

        private void SaveFileBtn_Click(object sender, RoutedEventArgs e)
        {
            SaveFile();
        }


        private void PageView_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        {
            UIElement pageView = sender as UIElement;
            if (pageView != null)
            {
                pageView.MouseLeftButtonUp -= PageView_MouseLeftButtonUp;
            }
            if (lastPDFEditEvent != null && lastPDFEditEvent.EditType == CPDFEditType.EditImage)
            {
                if (imageEditControl == null)
                {
                    imageEditControl = new PDFImageEditControl();
                }
                imageEditControl.InitWithPDFViewer(pdfViewControl.PDFView);
                imageEditControl.SetPDFImageEditData(lastPDFEditEvent);
                pdfEditControl = imageEditControl as UIElement;
                PropertyContainer.Child = pdfEditControl;
                ExpandRightPropertyPanel(pdfEditControl, Visibility.Visible);
            }
        }

        private void PageInfoBtn_Click(object sender, RoutedEventArgs e)
        {
            PasswordUI.Visibility = Visibility.Collapsed;
            FileInfoUI.Visibility = Visibility.Visible;
            FileInfoControl.InitWithPDFViewer(pdfViewControl.PDFView);
            PopupBorder.Visibility = Visibility.Visible;
        }

        private void FileInfoCloseBtn_Click(object sender, RoutedEventArgs e)
        {
            PopupBorder.Visibility = Visibility.Collapsed;
        }

        private void PDFTextEditButton_Click(object sender, RoutedEventArgs e)
        {
            ToggleButton senderBtn = sender as ToggleButton;
            if (senderBtn != null && pdfViewControl != null)
            {
                ClearPDFEditState(senderBtn);
                if (senderBtn.IsChecked == true)
                {
                    pdfViewControl.PDFView?.SetMouseMode(MouseModes.PanTool);
                    pdfViewControl.PDFView?.SetPDFEditType(CPDFEditType.EditText);
                    pdfViewControl.PDFView?.SetPDFEditCreateType(CPDFEditType.EditText);
                    pdfViewControl.PDFView?.SetMouseMode(MouseModes.PDFEdit);
                    pdfViewControl.PDFView?.ReloadDocument();
                }
                else
                {
                    pdfViewControl.PDFView?.SetPDFEditCreateType(CPDFEditType.None);
                    pdfViewControl.PDFView?.SetPDFEditType(CPDFEditType.EditImage | CPDFEditType.EditText);
                    pdfViewControl.PDFView?.SetMouseMode(MouseModes.PDFEdit);
                    pdfViewControl.PDFView?.ReloadDocument();
                }
            }
        }

        private void PDFImageEditButton_Click(object sender, RoutedEventArgs e)
        {
            ToggleButton senderBtn = sender as ToggleButton;
            if (senderBtn != null && pdfViewControl != null)
            {
                senderBtn.IsChecked = false;
                OpenFileDialog openFileDialog = new OpenFileDialog();
                openFileDialog.Filter = "Image Files(*.jpg;*.jpeg;*.png;*.bmp)|*.jpg;*.jpeg;*.png;*.bmp;";
                if (openFileDialog.ShowDialog() == true)
                {
                    ClearPDFEditState(senderBtn);
                    pdfViewControl.PDFView?.ClearSelectPDFEdit();
                    pdfViewControl.PDFView?.SetPDFEditType(CPDFEditType.EditImage | CPDFEditType.EditText);
                    pdfViewControl.PDFView?.SetMouseMode(MouseModes.PDFEdit);
                    pdfViewControl.PDFView?.ReloadDocument();

                    ExpandRightPropertyPanel(null, Visibility.Collapsed);
                    pdfViewControl.PDFView?.SetPDFEditCreateType(CPDFEditType.EditImage);
                    pdfViewControl.PDFView?.AddPDFEditImage(openFileDialog.FileName);
                }
            }
        }

        private void UndoBtn_Click(object sender, RoutedEventArgs e)
        {
            if (pdfViewControl != null && pdfViewControl.PDFView != null)
            {
                pdfViewControl.PDFView.UndoManager?.Undo();
            }
        }

        private void RedoBtn_Click(object sender, RoutedEventArgs e)
        {
            if (pdfViewControl != null && pdfViewControl.PDFView != null)
            {
                pdfViewControl.PDFView.UndoManager?.Redo();
            }
        }

        private void ClearPDFEditState(ToggleButton ignoreBtn = null)
        {
            List<ToggleButton> clearBtnList = new List<ToggleButton>()
            {
                PDFTextEditButton,
                PDFImageEditButton
            };

            foreach (ToggleButton item in clearBtnList)
            {
                if (ignoreBtn == item)
                {
                    continue;
                }
                item.IsChecked = false;
            }
        }

        private void PdfAnnotationControl_ClearAnnotationBar(object sender, EventArgs e)
        {
            AnnotationBarControl.ClearAllToolState();
        }

        private void AnnotationBarControl_AnnotationCancel(object sender, EventArgs e)
        {
            pdfAnnotationControl.AnnotationCancel();
            ExpandRightPropertyPanel(null, Visibility.Collapsed);
            RightPanelButton.IsChecked = false;
            ViewSettingBtn.IsChecked = false;
        }
        #endregion

        #region ContextMenu

        /// <summary>
        /// Annotation Context menu
        /// </summary> 
        private void PDFView_AnnotCommandHandler(object sender, ComPDFKitViewer.AnnotEvent.AnnotCommandArgs e)
        {
            switch (e.CommandType)
            {
                case CommandType.Context:
                    e.Handle = true;
                    if (e.CommandTarget == TargetType.Annot)
                    {
                        e.Handle = true;
                        e.PopupMenu = new ContextMenu();
                        if (e.PressOnLink && AnnotationBarControl.CurrentMode == "Link")
                        {
                            e.PopupMenu.Items.Add(new MenuItem() { Header = "Delete", Command = ApplicationCommands.Delete, CommandTarget = (UIElement)sender });
                            MenuItem propertyMenu = new MenuItem();
                            propertyMenu = new MenuItem();
                            propertyMenu.Header = "Edit";
                            WeakEventManager<MenuItem, RoutedEventArgs>.AddHandler(propertyMenu, "Click", EditLink_Click);
                            propertyMenu.CommandParameter = e;
                            e.PopupMenu.Items.Add(propertyMenu);
                        }
                        else if (e.PressOnAnnot)
                        {
                            e.PopupMenu.Items.Add(new MenuItem() { Header = "Delete", Command = ApplicationCommands.Delete, CommandTarget = (UIElement)sender });
                            e.PopupMenu.Items.Add(new MenuItem() { Header = "Copy", Command = ApplicationCommands.Copy, CommandTarget = (UIElement)sender });
                            e.PopupMenu.Items.Add(new MenuItem() { Header = "Cut", Command = ApplicationCommands.Cut, CommandTarget = (UIElement)sender });
                        }
                        else if (e.PressOnMedia || e.PressOnSound)
                        {
                            e.Handle = true;
                            e.PopupMenu.Items.Add(new MenuItem() { Header = "Play", Command = MediaCommands.Play, CommandTarget = (UIElement)sender, CommandParameter = e });
                            e.PopupMenu.Items.Add(new MenuItem() { Header = "Delete", Command = ApplicationCommands.Delete, CommandTarget = (UIElement)sender });
                        }
                        else if (e.PressOnSelectedText)
                        {
                            e.PopupMenu.Items.Add(new MenuItem() { Header = "Copy", Command = ApplicationCommands.Copy, CommandTarget = (UIElement)sender });
                        }
                        else
                        {
                            e.Handle = true;
                            e.PopupMenu = new ContextMenu();

                            if (currentMode == "Annotations")
                            {
                                e.PopupMenu.Items.Add(new MenuItem() { Header = "Paste", Command = ApplicationCommands.Paste, CommandTarget = (UIElement)sender });
                                e.PopupMenu.Items.Add(new Separator());
                            }


                            MenuItem fitWidthMenu = new MenuItem();
                            fitWidthMenu.Header = "Automatically Resize";
                            fitWidthMenu.Click += (o, p) =>
                            {
                                if (pdfViewControl != null)
                                {
                                    pdfViewControl.PDFView?.ChangeFitMode(FitMode.FitWidth);
                                }
                            };

                            e.PopupMenu.Items.Add(fitWidthMenu);

                            MenuItem fitSizeMenu = new MenuItem();
                            fitSizeMenu.Header = "Actual Size";
                            fitSizeMenu.Click += (o, p) =>
                            {
                                if (pdfViewControl != null)
                                {
                                    pdfViewControl.PDFView?.ChangeFitMode(FitMode.FitSize);
                                }
                            };

                            e.PopupMenu.Items.Add(fitSizeMenu);

                            MenuItem zoomInMenu = new MenuItem();
                            zoomInMenu.Header = "Zoom In";
                            zoomInMenu.Click += (o, p) =>
                            {
                                if (pdfViewControl != null)
                                {
                                    double newZoom = CheckZoomLevel(pdfViewControl.PDFView.ZoomFactor + 0.01, true);
                                    pdfViewControl.PDFView?.Zoom(newZoom);
                                }
                            };

                            e.PopupMenu.Items.Add(zoomInMenu);

                            MenuItem zoomOutMenu = new MenuItem();
                            zoomOutMenu.Header = "Zoom Out";
                            zoomOutMenu.Click += (o, p) =>
                            {
                                if (pdfViewControl != null)
                                {
                                    double newZoom = CheckZoomLevel(pdfViewControl.PDFView.ZoomFactor - 0.01, false);
                                    pdfViewControl.PDFView?.Zoom(newZoom);
                                }
                            };

                            e.PopupMenu.Items.Add(zoomOutMenu);
                            e.PopupMenu.Items.Add(new Separator());

                            MenuItem singleView = new MenuItem();
                            singleView.Header = "Single Page";
                            singleView.Click += (o, p) =>
                            {
                                if (pdfViewControl != null)
                                {
                                    pdfViewControl.PDFView?.ChangeViewMode(ViewMode.Single);
                                }
                            };

                            e.PopupMenu.Items.Add(singleView);

                            MenuItem singleContinuousView = new MenuItem();
                            singleContinuousView.Header = "Single Page Continuous";
                            singleContinuousView.Click += (o, p) =>
                            {
                                if (pdfViewControl != null)
                                {
                                    pdfViewControl.PDFView?.ChangeViewMode(ViewMode.SingleContinuous);
                                }
                            };

                            e.PopupMenu.Items.Add(singleContinuousView);

                            MenuItem doubleView = new MenuItem();
                            doubleView.Header = "Two Pages";
                            doubleView.Click += (o, p) =>
                            {
                                if (pdfViewControl != null)
                                {
                                    pdfViewControl.PDFView?.ChangeViewMode(ViewMode.Double);
                                }
                            };

                            e.PopupMenu.Items.Add(doubleView);

                            MenuItem doubleContinuousView = new MenuItem();
                            doubleContinuousView.Header = "Two Pages Continuous";
                            doubleContinuousView.Click += (o, p) =>
                            {
                                if (pdfViewControl != null)
                                {
                                    pdfViewControl.PDFView?.ChangeViewMode(ViewMode.DoubleContinuous);
                                }
                            };

                            e.PopupMenu.Items.Add(doubleContinuousView);
                        }
                    }

                    else if (e.CommandTarget == TargetType.ImageSelection)
                    {
                        if (pdfViewControl != null && pdfViewControl.PDFView != null && pdfViewControl.PDFView.GetSelectImageCount() > 0)
                        {
                            e.Handle = true;
                            e.PopupMenu = new ContextMenu();

                            MenuItem imageCopyMenu = new MenuItem();
                            imageCopyMenu = new MenuItem();
                            imageCopyMenu.Header = "Copy Images";
                            WeakEventManager<MenuItem, RoutedEventArgs>.AddHandler(imageCopyMenu, "Click", CopyImage_Click);
                            imageCopyMenu.CommandParameter = e;
                            e.PopupMenu.Items.Add(imageCopyMenu);

                            MenuItem imageExtraMenu = new MenuItem();
                            imageExtraMenu = new MenuItem();
                            imageExtraMenu.Header = "Extract Images";
                            WeakEventManager<MenuItem, RoutedEventArgs>.AddHandler(imageExtraMenu, "Click", ExtraImage_Click);
                            imageExtraMenu.CommandParameter = e;
                            e.PopupMenu.Items.Add(imageExtraMenu);
                        }
                    }
                    break;
                case CommandType.Copy:
                    e.DoCommand();
                    break;
                case CommandType.Cut:
                case CommandType.Paste:
                case CommandType.Delete:
                    e.DoCommand();
                    break;
                default:
                    break;
            }
        }

        /// <summary>
        /// TextEdit context menu.
        /// </summary>
        private void PDFEditTextContextMenu(object sender, PDFEditCommand editCommand)
        {
            editCommand.PopupMenu = new ContextMenu();
            if (lastPDFEditEvent != null)
            {
                editCommand.PopupMenu.Items.Add(new MenuItem() { Header = "Copy", Command = ApplicationCommands.Copy, CommandTarget = (UIElement)sender });
                editCommand.PopupMenu.Items.Add(new MenuItem() { Header = "Cut", Command = ApplicationCommands.Cut, CommandTarget = (UIElement)sender });
                editCommand.PopupMenu.Items.Add(new MenuItem() { Header = "Delete", Command = ApplicationCommands.Delete, CommandTarget = (UIElement)sender });
                editCommand.PopupMenu.Items.Add(new MenuItem() { Header = "Paste", Command = ApplicationCommands.Paste, CommandTarget = (UIElement)sender });
            }
            else
            {
                editCommand.PopupMenu.Items.Add(new MenuItem() { Header = "Paste", Command = ApplicationCommands.Paste, CommandTarget = (UIElement)sender });
                if (editCommand.TextAreaCopied)
                {
                    editCommand.PopupMenu.Items.Add(new MenuItem() { Header = "Paste And Match Style", Command = CustomCommands.PasteMatchStyle, CommandTarget = (UIElement)sender });
                }
            }
        }

        /// <summary>
        /// ImageEdit right-click menu.
        /// </summary>
        private void PDFEditImageContextMenu(object sender, PDFEditCommand editCommand)
        {
            editCommand.PopupMenu = new ContextMenu();
            if (lastPDFEditEvent != null)
            {
                MenuItem rotateLeftMenu = new MenuItem();
                rotateLeftMenu.Header = "Left Rotate";
                rotateLeftMenu.Click += (o, p) =>
                {
                    if (lastPDFEditEvent != null && lastPDFEditEvent.EditType == CPDFEditType.EditImage)
                    {
                        lastPDFEditEvent.Rotate = -90;
                        lastPDFEditEvent.UpdatePDFEditByEventArgs();
                        imageEditControl?.SetImageThumb();
                    }
                };
                editCommand.PopupMenu.Items.Add(rotateLeftMenu);

                MenuItem rotateRightMenu = new MenuItem();
                rotateRightMenu.Header = "Right Rotate";
                rotateRightMenu.Click += (o, p) =>
                {
                    if (lastPDFEditEvent != null && lastPDFEditEvent.EditType == CPDFEditType.EditImage)
                    {
                        lastPDFEditEvent.Rotate = 90;
                        lastPDFEditEvent.UpdatePDFEditByEventArgs();
                        imageEditControl?.SetImageThumb();
                    }
                };
                editCommand.PopupMenu.Items.Add(rotateRightMenu);

                MenuItem replaceMenu = new MenuItem();
                replaceMenu.Header = "Replace";
                replaceMenu.Click += (o, p) =>
                {
                    if (lastPDFEditEvent != null && lastPDFEditEvent.EditType == CPDFEditType.EditImage)
                    {
                        OpenFileDialog openFileDialog = new OpenFileDialog();
                        openFileDialog.Filter = "Image Files(*.jpg;*.jpeg;*.png;*.bmp)|*.jpg;*.jpeg;*.png;*.bmp;";
                        if (openFileDialog.ShowDialog() == true)
                        {
                            lastPDFEditEvent.ReplaceImagePath = openFileDialog.FileName;
                            lastPDFEditEvent.UpdatePDFEditByEventArgs();
                            pdfViewControl.PDFView?.ClearSelectPDFEdit();
                            imageEditControl?.SetImageThumb();
                        }
                    }
                };
                editCommand.PopupMenu.Items.Add(replaceMenu);

                MenuItem exportMenu = new MenuItem();
                exportMenu.Header = "Export";
                exportMenu.Click += (o, p) =>
                {
                    if (pdfViewControl != null && pdfViewControl.PDFView != null)
                    {
                        Dictionary<int, List<Bitmap>> imageDict = pdfViewControl.PDFView.GetSelectedImages();
                        if (imageDict != null && imageDict.Count > 0)
                        {
                            System.Windows.Forms.FolderBrowserDialog folderBrowser = new System.Windows.Forms.FolderBrowserDialog();
                            if (folderBrowser.ShowDialog() == System.Windows.Forms.DialogResult.OK)
                            {
                                string choosePath = folderBrowser.SelectedPath;
                                string openPath = choosePath;
                                foreach (int pageIndex in imageDict.Keys)
                                {
                                    List<Bitmap> imageList = imageDict[pageIndex];
                                    foreach (Bitmap image in imageList)
                                    {
                                        string savePath = System.IO.Path.Combine(choosePath, Guid.NewGuid() + ".jpg");
                                        image.Save(savePath, System.Drawing.Imaging.ImageFormat.Jpeg);
                                        openPath = savePath;
                                    }
                                }
                                Process.Start("explorer", "/select,\"" + openPath + "\"");
                            }
                        }
                    }
                };
                editCommand.PopupMenu.Items.Add(exportMenu);

                MenuItem opacityMenu = new MenuItem();
                opacityMenu.Header = "Opacity";
                editCommand.PopupMenu.Items.Add(opacityMenu);

                AppendOpacityMenu(opacityMenu);

                MenuItem horizonMirror = new MenuItem();
                horizonMirror.Header = "HMirror";
                horizonMirror.Click += (o, p) =>
                {
                    if (lastPDFEditEvent != null && lastPDFEditEvent.EditType == CPDFEditType.EditImage)
                    {
                        lastPDFEditEvent.HorizontalMirror = true;
                        lastPDFEditEvent.UpdatePDFEditByEventArgs();
                    }
                };
                editCommand.PopupMenu.Items.Add(horizonMirror);

                MenuItem verticalMirror = new MenuItem();
                verticalMirror.Header = "VMirror";
                verticalMirror.Click += (o, p) =>
                {
                    if (lastPDFEditEvent != null && lastPDFEditEvent.EditType == CPDFEditType.EditImage)
                    {
                        lastPDFEditEvent.VerticalMirror = true;
                        lastPDFEditEvent.UpdatePDFEditByEventArgs();
                    }
                };
                editCommand.PopupMenu.Items.Add(verticalMirror);

                MenuItem cropMenu = new MenuItem();
                cropMenu.Header = "Crop";
                cropMenu.Click += (o, p) =>
                {
                    if (lastPDFEditEvent != null && lastPDFEditEvent.EditType == CPDFEditType.EditImage)
                    {
                        lastPDFEditEvent.ClipImage = true;
                        lastPDFEditEvent.UpdatePDFEditByEventArgs();
                    }
                };
                editCommand.PopupMenu.Items.Add(cropMenu);

                editCommand.PopupMenu.Items.Add(new MenuItem() { Header = "Copy", Command = ApplicationCommands.Copy, CommandTarget = (UIElement)sender });
                editCommand.PopupMenu.Items.Add(new MenuItem() { Header = "Cut", Command = ApplicationCommands.Cut, CommandTarget = (UIElement)sender });
                editCommand.PopupMenu.Items.Add(new MenuItem() { Header = "Delete", Command = ApplicationCommands.Delete, CommandTarget = (UIElement)sender });
            }
            else
            {
                editCommand.PopupMenu.Items.Add(new MenuItem() { Header = "Paste", Command = ApplicationCommands.Paste, CommandTarget = (UIElement)sender });
            }
        }

        /// <summary>
        /// ImageEdit transparency submenu.
        /// </summary>
        private void AppendOpacityMenu(MenuItem parentMenu)
        {
            List<int> opacityList = new List<int>()
            {
                25,50,75,100
            };

            foreach (int opacity in opacityList)
            {
                MenuItem opacityMenu = new MenuItem();
                opacityMenu.Header = string.Format("{0}%", opacity);
                opacityMenu.Click += (o, p) =>
                {
                    if (lastPDFEditEvent != null && lastPDFEditEvent.EditType == CPDFEditType.EditImage)
                    {
                        lastPDFEditEvent.Transparency = (int)Math.Ceiling(opacity * 255 / 100D);
                        lastPDFEditEvent.UpdatePDFEditByEventArgs();
                    }
                };
                parentMenu.Items.Add(opacityMenu);
            }
        }

        private void ExtraImage_Click(object sender, RoutedEventArgs e)
        {
            System.Windows.Forms.FolderBrowserDialog folderDialog = new System.Windows.Forms.FolderBrowserDialog();
            if (folderDialog.ShowDialog() == System.Windows.Forms.DialogResult.OK)
            {
                string choosePath = folderDialog.SelectedPath;
                string openPath = choosePath;
                Dictionary<int, List<Bitmap>> imageDict = pdfViewControl.PDFView?.GetSelectedImages();

                if (imageDict != null && imageDict.Count > 0)
                {
                    foreach (int pageIndex in imageDict.Keys)
                    {
                        List<Bitmap> imageList = imageDict[pageIndex];
                        foreach (Bitmap image in imageList)
                        {
                            string savePath = Path.Combine(choosePath, Guid.NewGuid() + ".jpg");
                            image.Save(savePath, System.Drawing.Imaging.ImageFormat.Jpeg);
                            openPath = savePath;
                        }
                    }
                }
                Process.Start("explorer", "/select,\"" + openPath + "\"");
            }
        }

        private void CopyImage_Click(object sender, RoutedEventArgs e)
        {
            Dictionary<int, List<Bitmap>> imageDict = pdfViewControl.PDFView?.GetSelectedImages();

            if (imageDict != null && imageDict.Count > 0)
            {
                foreach (int pageIndex in imageDict.Keys)
                {
                    List<Bitmap> imageList = imageDict[pageIndex];
                    foreach (Bitmap image in imageList)
                    {
                        MemoryStream ms = new MemoryStream();
                        image.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
                        BitmapImage imageData = new BitmapImage();
                        imageData.BeginInit();
                        imageData.StreamSource = ms;
                        imageData.CacheOption = BitmapCacheOption.OnLoad;
                        imageData.EndInit();
                        imageData.Freeze();
                        Clipboard.SetImage(imageData);
                        break;
                    }
                }
            }
        }
        #endregion

        #region Property changed

        protected void OnPropertyChanged([CallerMemberName] string name = null)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));
        }

        #endregion

        #region Open and save file

        public void InitWithFilePath(string filePath)
        {
            pdfViewControl = new PDFViewControl();
            pdfViewControl.PDFView.InitDocument(filePath);
        }

        private void LoadDocument()
        {
            //Load the Document
            pdfViewControl.PDFView?.Load();

            //Highlight the link annotation
            pdfViewControl.PDFView?.SetShowLink(true);

            //Add PDFViewControl to PDFGrid
            PDFGrid.Child = pdfViewControl;

            // Register the InfoChanged event handler,
            // which is used to notify the CPDFScalingControl of real-time changes in the displayed number when the page size changes.
            pdfViewControl.PDFView.InfoChanged -= PdfViewer_InfoChanged;
            pdfViewControl.PDFView.InfoChanged += PdfViewer_InfoChanged;

            //
            pdfViewControl.PDFView.PDFEditCommandHandler -= PDFView_PDFEditCommandHandler;
            pdfViewControl.PDFView.PDFEditCommandHandler += PDFView_PDFEditCommandHandler;

            pdfViewControl.PDFView.AnnotCommandHandler -= PDFView_AnnotCommandHandler;
            pdfViewControl.PDFView.AnnotCommandHandler += PDFView_AnnotCommandHandler;

            pdfViewControl.PDFView.UndoManager.PropertyChanged -= UndoManager_PropertyChanged;
            pdfViewControl.PDFView.UndoManager.PropertyChanged += UndoManager_PropertyChanged;

            pdfViewControl.PDFView.SetFormFieldHighlight(true);

            PasswordUI.Closed -= PasswordUI_Closed;
            PasswordUI.Canceled -= PasswordUI_Canceled;
            PasswordUI.Confirmed -= PasswordUI_Confirmed;
            PasswordUI.Confirmed += PasswordUI_Confirmed;
            PasswordUI.Canceled += PasswordUI_Canceled;
            PasswordUI.Closed += PasswordUI_Closed;

            pdfViewControl.PDFView.ChangeFitMode(FitMode.FitWidth);
            CPDFSaclingControl.InitWithPDFViewer(pdfViewControl.PDFView);
            CPDFSaclingControl.SetZoomTextBoxText(string.Format("{0}", (int)(pdfViewControl.PDFView.ZoomFactor * 100)));

            InitialPDFViewControl(pdfViewControl);
            pdfViewControl.PDFView.SetMouseMode(MouseModes.Viewer);

            FloatPageTool.InitWithPDFViewer(pdfViewControl.PDFView);
            BotaSideTool.InitWithPDFViewer(pdfViewControl.PDFView);
            BotaSideTool.SelectBotaTool(BOTATools.Thumbnail);
            ViewSettingBtn.IsChecked = false;
            PropertyContainer.Child = null;
            PropertyContainer.Visibility = Visibility.Collapsed;
        }

        /// <summary>
        /// Save the file to another PDF file.
        /// </summary>
        public void SaveAsFile()
        {
            {
                if (pdfViewControl != null && pdfViewControl.PDFView != null && pdfViewControl.PDFView.Document != null)
                {
                    CPDFDocument pdfDoc = pdfViewControl.PDFView.Document;
                    SaveFileDialog saveDialog = new SaveFileDialog();
                    saveDialog.Filter = "(*.pdf)|*.pdf";
                    saveDialog.DefaultExt = ".pdf";
                    saveDialog.OverwritePrompt = true;

                    if (saveDialog.ShowDialog() == true)
                    {
                        pdfDoc.WriteToFilePath(saveDialog.FileName);
                    }
                }
            }
        }

        /// <summary>
        /// Save the file in the current path.
        /// </summary>
        public void SaveFile()
        {
            if (pdfViewControl != null && pdfViewControl.PDFView != null && pdfViewControl.PDFView.Document != null)
            {
                CPDFDocument pdfDoc = pdfViewControl.PDFView.Document;
                if (pdfDoc.WriteToLoadedPath())
                {
                    pdfViewControl.PDFView.UndoManager.CanSave = false;
                    return;
                }

                SaveFileDialog saveDialog = new SaveFileDialog();
                saveDialog.Filter = "(*.pdf)|*.pdf";
                saveDialog.DefaultExt = ".pdf";
                saveDialog.OverwritePrompt = true;

                if (saveDialog.ShowDialog() == true)
                {
                    pdfDoc.WriteToFilePath(saveDialog.FileName);
                }
            }
        }

        public void OpenFile()
        {
            string filePath = CommonHelper.GetFilePathOrEmpty();
            string oldFilePath = pdfViewControl.PDFView.Document.FilePath;

            if (!string.IsNullOrEmpty(filePath) && pdfViewControl != null)
            {
                if (pdfViewControl.PDFView != null && pdfViewControl.PDFView.Document != null)
                {
                    if (oldFilePath.ToLower() == filePath.ToLower())
                    {
                        return;
                    }
                }

                if ((bool)CheckExistBeforeOpenFileEvent?.Invoke(new string[] { filePath, oldFilePath }))
                {
                    return;
                }

                passwordViewer = new PDFViewControl();
                passwordViewer.PDFView.InitDocument(filePath);
                if (passwordViewer.PDFView.Document == null)
                {
                    MessageBox.Show("Open File Failed");
                    return;
                }

                if (passwordViewer.PDFView.Document.IsLocked)
                {
                    PasswordUI.SetShowText(System.IO.Path.GetFileName(filePath) + " password encrypted.");
                    PasswordUI.ClearPassword();
                    PopupBorder.Visibility = Visibility.Visible;
                    PasswordUI.Visibility = Visibility.Visible;
                }
                else
                {
                    pdfViewControl = passwordViewer;
                    LoadDocument();
                    FileChangeEvent?.Invoke(null, EventArgs.Empty);
                }
            }
        }

        private void OpenFile_Click(object sender, RoutedEventArgs e)
        {
            OpenFile();
        }
        #endregion

        #region ToolPanel expand and collapse
        private void ExpandLeftPanel(bool isExpand)
        {
            BotaSideTool.Visibility = isExpand ? Visibility.Visible : Visibility.Collapsed;
            Splitter.Visibility = isExpand ? Visibility.Visible : Visibility.Collapsed;
            if (isExpand)
            {
                BodyGrid.ColumnDefinitions[0].Width = new GridLength(320);
                BodyGrid.ColumnDefinitions[1].Width = new GridLength(15);
            }
            else
            {
                BodyGrid.ColumnDefinitions[0].Width = new GridLength(0);
                BodyGrid.ColumnDefinitions[1].Width = new GridLength(0);
            }
        }

        private void LeftToolPanelButton_Click(object sender, RoutedEventArgs e)
        {
            ToggleButton expandBtn = sender as ToggleButton;
            if (expandBtn != null)
            {
                bool isExpand = expandBtn.IsChecked == true;
                ExpandLeftPanel(isExpand);
            }
        }

        private void ExpandSearchBtn_Click(object sender, RoutedEventArgs e)
        {
            ExpandLeftPanel(true);
            LeftToolPanelButton.IsChecked = true;
            BotaSideTool.SelectBotaTool(BOTATools.Search);
        }

        private void ViewSettingBtn_Click(object sender, RoutedEventArgs e)
        {
            ToggleButton toggleButton = sender as ToggleButton;
            if (toggleButton != null)
            {
                if (toggleButton.IsChecked == true)
                {
                    if (displayPanel == null)
                    {
                        displayPanel = new CPDFDisplaySettingsControl();
                    }
                    displayPanel.InitWithPDFViewer(pdfViewControl.PDFView);
                    PropertyContainer.Child = displayPanel;
                    PropertyContainer.Visibility = Visibility.Visible;
                    if ((bool)RightPanelButton.IsChecked)
                    {
                        RightPanelButton.IsChecked = false;
                    }
                }
                else
                {
                    PropertyContainer.Child = null;
                    PropertyContainer.Visibility = Visibility.Collapsed;
                }
            }
        }

        public void ExpandRightPropertyPanel(UIElement properytPanel, Visibility visible)
        {
            PropertyContainer.Width = 260;
            PropertyContainer.Child = properytPanel;
            PropertyContainer.Visibility = visible;
            if (visible == Visibility.Hidden || visible == Visibility.Collapsed)
            {
                RightPanelButton.IsChecked = false;
            }
        }

        private void RightPanelButton_Click(object sender, RoutedEventArgs e)
        {
            ToggleButton toggleButton = sender as ToggleButton;
            if (toggleButton != null)
            {
                if (toggleButton.IsChecked == true)
                {
                    if (currentMode == "Annotation")
                    {
                        ExpandRightPropertyPanel(pdfAnnotationControl, Visibility.Visible);
                    }
                    else if (currentMode == "Edit")
                    {
                        ExpandRightPropertyPanel(pdfEditControl, Visibility.Visible);
                    }
                    else if (currentMode == "Forms")
                    {
                        ExpandRightPropertyPanel(pdfFormControl, Visibility.Visible);
                    }
                    else
                    {
                        ExpandRightPropertyPanel(pdfAnnotationControl, Visibility.Visible);
                    }
                    if ((bool)ViewSettingBtn.IsChecked)
                    {
                        ViewSettingBtn.IsChecked = false;
                    }
                }
                else
                {
                    ExpandRightPropertyPanel(null, Visibility.Collapsed);
                }
            }
        }
        #endregion

        #region Event handle

        private void AnnotationBarControl_AnnotationPropertyChanged(object sender, CPDFAnnotationType e)
        {
            pdfAnnotationControl.LoadAnnotationPanel(e);
            if (e != CPDFAnnotationType.Audio && e != CPDFAnnotationType.Image)
            {
                ExpandRightPropertyPanel(pdfAnnotationControl, Visibility.Visible);
                RightPanelButton.IsChecked = true;
            }
        }

        private void PDFView_AnnotActiveHandler(object sender, AnnotAttribEvent e)
        {
            PropertyContainer.Child = pdfAnnotationControl;
            pdfAnnotationControl.SetAnnotEventData(e);
        }

        private void PDFView_WidgetClickHandler(object sender, WidgetArgs e)
        {
            if (e is WidgetSignArgs)
            {
                RightPanelButton.IsChecked = true;
                ExpandRightPropertyPanel(pdfFormControl, Visibility.Visible);
                pdfFormControl.SetPropertyForType(e, null);
            }
            else
            {
                RightPanelButton.IsChecked = false;
                ExpandRightPropertyPanel(null, Visibility.Collapsed);
            }
        }


        private void PDFView_PDFEditCommandHandler(object sender, PDFEditCommand e)
        {
            if (e == null)
            {
                return;
            }

            if (e.EditType == CPDFEditType.EditText)
            {
                e.Handle = true;
                PDFEditTextContextMenu(sender, e);
            }

            if (e.EditType == CPDFEditType.EditImage)
            {
                e.Handle = true;
                PDFEditImageContextMenu(sender, e);
            }
        }

        /// <summary>
        /// Text and Image Selected Event
        /// </summary>
        private void PDFView_PDFEditActiveHandler(object sender, ComPDFKitViewer.PDFEditEvent e)
        {
            lastPDFEditEvent = e;
            ViewSettingBtn.IsChecked = false;
            if (e == null)
            {
                pdfEditControl = null;
                PropertyContainer.Child = pdfEditControl;
                ExpandRightPropertyPanel(null, Visibility.Collapsed);
                return;
            }
            if (Mouse.RightButton == MouseButtonState.Pressed)
            {
                return;
            }
            if (e.EditType == CPDFEditType.EditText)
            {
                RightPanelButton.IsChecked = true;
                PDFTextEditControl textEditControl = new PDFTextEditControl();
                textEditControl.SetPDFTextEditData(e);
                pdfEditControl = textEditControl as UIElement;
                PropertyContainer.Child = pdfEditControl;
                ExpandRightPropertyPanel(pdfEditControl, Visibility.Visible);
                return;
            }

            if (e.EditType == CPDFEditType.EditImage && pdfViewControl != null)
            {
                RightPanelButton.IsChecked = true;
                UIElement pageView = sender as UIElement;
                if (pageView != null)
                {
                    pageView.MouseLeftButtonUp += PageView_MouseLeftButtonUp; ;
                }
                return;
            }
        }

        private void PDFView_FormEditHandler(object sender, List<AnnotEditEvent> e)
        {
            if (e != null && e.Count > 0)
            {
                AnnotEditEvent editEvent = e[e.Count - 1];
                if (editEvent.EditAction == ActionType.Add)
                {
                    pdfViewControl.PDFView.SelectAnnotation(editEvent.PageIndex, editEvent.AnnotIndex);
                }
            }
        }

        private void PDFView_FormActiveHandler(object sender, AnnotAttribEvent e)
        {
            if (e == null || e.IsAnnotCreateReset)
            {
                pdfFormControl.SetPropertyForType(null, null);
            }
            else
            {
                switch (e.GetAnnotTypes())
                {
                    case AnnotArgsType.WidgetViewForm:
                        WidgetArgs formArgs = e.GetAnnotHandlerEventArgs(AnnotArgsType.WidgetViewForm).First() as WidgetArgs;
                        switch (formArgs.WidgeType)
                        {
                            case ComPDFKit.PDFAnnotation.Form.C_WIDGET_TYPE.WIDGET_PUSHBUTTON:
                            case ComPDFKit.PDFAnnotation.Form.C_WIDGET_TYPE.WIDGET_COMBOBOX:
                            case ComPDFKit.PDFAnnotation.Form.C_WIDGET_TYPE.WIDGET_LISTBOX:
                                ExpandRightPropertyPanel(pdfFormControl, Visibility.Visible);
                                if ((bool)ViewSettingBtn.IsChecked)
                                {
                                    ViewSettingBtn.IsChecked = false;
                                }
                                RightPanelButton.IsChecked = true;
                                break;
                            default:
                                break;
                        }
                        pdfFormControl.SetPropertyForType(formArgs, e);
                        break;
                }
            }
        }

        private void PageEditControl_ExitPageEdit(object sender, EventArgs e)
        {
            ModeComboBox.SelectedIndex = 0;
        }

        private void PageEditControl_PageMoved(object sender, RoutedEventArgs e)
        {
            if (pdfViewControl == null || pdfViewControl.PDFView == null)
            {
                return;
            }
            BotaSideTool.InitWithPDFViewer(pdfViewControl.PDFView);
        }

        private void CPDFPageEditBarControl_PageEditEvent(object sender, string e)
        {
            pageEditControl.PageEdit(e);
        }


        private void CPDFTitleBarControl_SaveFileEvent(object sender, EventArgs e)
        {
            SaveFile();
        }

        private void CPDFTitleBarControl_SaveAsFileEvent(object sender, EventArgs e)
        {
            SaveAsFile();
        }

        private void CPDFTitleBarControl_OpenFileEvent(object sender, EventArgs e)
        {
            OpenFile();
        }
        #endregion

        #region Change mode

        /// <summary>
        /// Actions performed when switching modes:
        /// Separated into actions performed upon entering and exiting the mode.
        /// </summary>
        private void ComboBox_SelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if (isFirstLoad)
            {
                isFirstLoad = false;
                return;
            }

            var item = (sender as ComboBox).SelectedItem as ComboBoxItem;
            //Behavior when exit mode
            switch (currentMode)
            {
                case "Viewer":
                    break;
                /*
                 * Behavior when exit Edit mode
                 * Clear and collapse the ToolBar
                 * Clear And collapse the property panel.
                 * Change the mousemode to PanTool
                 * Unsubscribe the event handles
                 * Clear the undo history
                 */
                case "Annotations":
                    AnnotationBarControl.Visibility = Visibility.Collapsed;
                    AnnotationBarControl.ClearAllToolState();
                    pdfAnnotationControl.ClearPanel();
                    ExpandRightPropertyPanel(null, Visibility.Collapsed);
                    pdfViewControl.PDFView?.SetMouseMode(MouseModes.PanTool);
                    pdfViewControl.PDFView.AnnotEditHandler -= PDFView_AnnotEditHandler;
                    pdfAnnotationControl.ClearAnnotationBar -= PdfAnnotationControl_ClearAnnotationBar;
                    pdfViewControl.PDFView.AnnotActiveHandler -= PDFView_AnnotActiveHandler;
                    pdfViewControl.PDFView?.UndoManager.ClearHistory();
                    break;
                /*
                 * Behavior when exit edit mode:
                 * Collapsed the ToolBar
                 * Highlight the link annotation
                 * Set the mode to not allow edit
                 * Set the mouse mode to PanTool
                 * Reload Document
                 * Unsubscribe click event.
                 * Clear And collapse the property panel.
                 * Clear and collapse the ToolBar
                 * Clear undo history
                 * CPDFDisplaySettingsControl
                 * Enable the configuration of the split view.
                 */
                case "Content Editor":
                    PDFEditTool.Visibility = Visibility.Collapsed;
                    pdfViewControl.PDFView?.SetShowLink(true);
                    pdfViewControl.PDFView?.SetPDFEditType(CPDFEditType.None);
                    pdfViewControl.PDFView?.SetMouseMode(MouseModes.PanTool);
                    pdfViewControl.PDFView?.ReloadDocument();
                    pdfViewControl.PDFView.PDFEditActiveHandler -= PDFView_PDFEditActiveHandler;
                    ExpandRightPropertyPanel(null, Visibility.Collapsed);
                    ClearPDFEditState();
                    pdfViewControl.PDFView?.UndoManager.ClearHistory();
                    if (displayPanel != null)
                    {
                        displayPanel.SetSplitContainerVisibility(Visibility.Visible);
                    }
                    break;
                /*
                 * Behavior when exit form mode:
                 * Clear and collapsed the ToolBar
                 * Clear And Collapse the property panel. 
                 * Unsubscribe event.
                 * Clear undo history
                 */
                case "Forms":
                    ExpandRightPropertyPanel(null, Visibility.Collapsed);
                    FormBarControl.ClearAllToolState();
                    FormBarControl.Visibility = Visibility.Collapsed;
                    pdfViewControl.PDFView?.SetMouseMode(MouseModes.PanTool);
                    pdfViewControl.PDFView.AnnotActiveHandler -= PDFView_FormActiveHandler;
                    pdfViewControl.PDFView.AnnotEditHandler -= PDFView_FormEditHandler;
                    pdfViewControl.PDFView?.UndoManager.ClearHistory();
                    break;
                /*
                 * Unsubscribe event.
                 * Show Undo Redo Button
                 * Collapse PageEditBarControl
                 * Replace PDFGrid.Child to pdfViewControl.
                 * Reload Document
                 * Enable Button
                 */
                case "Docs Editor":
                    pageEditControl.ExitPageEdit -= PageEditControl_ExitPageEdit;
                    pageEditControl.PageMoved -= PageEditControl_PageMoved;
                    PageEditBarControl.PageEditEvent -= CPDFPageEditBarControl_PageEditEvent;
                    UndoRedoStackPanel.Visibility = Visibility.Visible;
                    PageEditBarControl.Visibility = Visibility.Collapsed;
                    PDFGrid.Child = pdfViewControl;
                    FloatPageTool.Visibility = Visibility.Visible;
                    pdfViewControl.PDFView.ReloadDocument();
                    LeftToolPanelButton.IsEnabled = true;
                    SearchButton.IsEnabled = true;
                    RightPanelButton.IsEnabled = true;
                    ViewSettingBtn.IsEnabled = true;
                    break;
                default:
                    break;
            }

            /* 
             * Behavior when switching to Viewer mode:
             * Hide the ToolBar
             * Set mousemode to Viewer
             */
            if ((string)item.Content == "Viewer")
            {
                ToolBarContainer.Visibility = Visibility.Collapsed;
                pdfViewControl.PDFView.SetMouseMode(MouseModes.Viewer);
            }

            /* 
             * Behavior when switching to Annotation mode:
             * Show the ToolBar
             * Show the AnnotationBar
             */

            else if ((string)item.Content == "Annotations")
            {
                ToolBarContainer.Visibility = Visibility.Visible;
                AnnotationBarControl.Visibility = Visibility.Visible;
                pdfViewControl.PDFView.SetMouseMode(MouseModes.PanTool);
                pdfAnnotationControl.ClearAnnotationBar += PdfAnnotationControl_ClearAnnotationBar;
                pdfViewControl.PDFView.AnnotEditHandler += PDFView_AnnotEditHandler;
                pdfViewControl.PDFView.AnnotActiveHandler += PDFView_AnnotActiveHandler;
            }

            /*
             * Behavior when switching to Edit mode:
             * Show the ToolBar
             * Show the EditBar
             * Set the mode to allow editing of both text and images
             * Set the mouse mode to PDFEdit
             * Reload Document
             * Set the splite mode to None and unable the split setting
            */
            else if ((string)item.Content == "Content Editor")
            {
                ToolBarContainer.Visibility = Visibility.Visible;
                PDFEditTool.Visibility = Visibility.Visible;
                PageEditBarControl.Visibility = Visibility.Collapsed;

                pdfViewControl.PDFView?.SetPDFEditType(CPDFEditType.EditText | CPDFEditType.EditImage);
                pdfViewControl.PDFView?.SetMouseMode(MouseModes.PDFEdit);
                pdfViewControl.PDFView?.ReloadDocument();

                pdfViewControl.PDFView.PDFEditActiveHandler += PDFView_PDFEditActiveHandler;
                pdfViewControl.PDFView.SetSplitMode(SplitMode.None);
                if (displayPanel != null)
                {
                    displayPanel.SetSplitContainerVisibility(Visibility.Collapsed);
                }
            }

            /*
             *  Behavior when switching to Form mode:
             *  
             */
            else if ((string)item.Content == "Forms")
            {
                ToolBarContainer.Visibility = Visibility.Visible;
                FormBarControl.Visibility = Visibility.Visible;

                pdfViewControl.PDFView?.SetShowLink(true);
                pdfViewControl.PDFView?.SetMouseMode(MouseModes.FormEditTool);

                pdfViewControl.PDFView?.ReloadDocument();
                pdfViewControl.PDFView.AnnotActiveHandler += PDFView_FormActiveHandler;
                pdfViewControl.PDFView.AnnotEditHandler += PDFView_FormEditHandler;
            }

            /*
             * 
             */
            else if ((string)item.Content == "Docs Editor")
            {
                ToolBarContainer.Visibility = Visibility.Visible;
                if (pageEditControl == null)
                {
                    pageEditControl = new CPDFPageEditControl();
                }
                pageEditControl.ExitPageEdit += PageEditControl_ExitPageEdit; ;
                pageEditControl.PageMoved += PageEditControl_PageMoved; ;
                PageEditBarControl.PageEditEvent += CPDFPageEditBarControl_PageEditEvent;
                pageEditControl.LoadThumbnails(pdfViewControl.PDFView);
                PDFGrid.Child = pageEditControl;
                UndoRedoStackPanel.Visibility = Visibility.Collapsed;
                PageEditBarControl.Visibility = Visibility.Visible;
                LeftToolPanelButton.IsChecked = false;
                LeftToolPanelButton.IsEnabled = false;
                SearchButton.IsEnabled = false;
                RightPanelButton.IsChecked = false;
                RightPanelButton.IsEnabled = false;
                ViewSettingBtn.IsChecked = false;
                ViewSettingBtn.IsEnabled = false;
                ExpandLeftPanel(false);
                ExpandRightPropertyPanel(null, Visibility.Collapsed);
                FloatPageTool.Visibility = Visibility.Collapsed;
            }

            currentMode = (string)item.Content;
        }

        #endregion
    }
}