kmpdfkit_demo/PDFViewer/View/CPDFDropDownView.m

//
//  DropDownView.m
//  PDFViewer
//
//  Created by kdanmobile_2 on 2022/11/21.
//

#import "CPDFDropDownView.h"

@implementation CPDFDropDownView

- (id)initWithFrame:(CGRect)frame WithString:(NSArray *)str{
    if (self = [super initWithFrame:frame]) {
        _list = str;
        _borderStyle = UITextBorderStyleRoundedRect;
        _showList = NO;
        _oldFrame = frame;
        _newFrame = CGRectMake(frame.origin.x, frame.origin.y, frame.size.width, frame.size.height*3);
        _lineColor = [UIColor lightGrayColor];
        _listBgcolor = [UIColor whiteColor];
        _lineWidth = 1;
        self.backgroundColor=[UIColor clearColor];

        [self drawView];
    }
    return self;
}

- (void)dropdown {
    [_textField resignFirstResponder];
    if (_showList) {
        return;
    } else {
        [self.superview bringSubviewToFront:self];
        [self setShowList:YES];
    }
    
}

- (void)drawView {
    //Textfield
    _textField = [[UITextField alloc] initWithFrame:CGRectMake(0, 0, _oldFrame.size.width, _oldFrame.size.height)];
    _textField.backgroundColor = [UIColor clearColor];
    _textField.opaque = YES;
    _textField.textColor = [UIColor blackColor];
    _textField.font = [UIFont fontWithName:@"Arial" size:12.0];
    _textField.borderStyle = _borderStyle;
    //_textField.textAlignment = UITextAlignmentLeft;
    [self addSubview:_textField];
    [_textField addTarget:self action:@selector(dropdown)forControlEvents:UIControlEventAllTouchEvents];
    //dropdown list
    _listView=[[UITableView alloc]initWithFrame:
     CGRectMake(_lineWidth,_oldFrame.size.height+_lineWidth,
    _oldFrame.size.width-_lineWidth*2,
    _oldFrame.size.height*2-_lineWidth*2)];
    _listView.dataSource = self;
    _listView.delegate = self;
    _listView.backgroundColor = _listBgcolor;
    _listView.separatorColor = _lineColor;
    _listView.hidden = !_showList;
    [self addSubview:_listView];
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    return  _list.count;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"listwid"];
    if (cell == nil) {
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:@"listwid"];
    }
    cell.textLabel.text = [_list objectAtIndex:indexPath.row];
    cell.textLabel.font = _textField.font;
    cell.selectionStyle = UITableViewCellSelectionStyleGray;
    return  cell;
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    return _oldFrame.size.height;
}

//When selecting a row in the drop-down list, set the value in the text box to hide the drop-down list
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    _textField.text = (NSString *)[_list objectAtIndex:indexPath.row];
    [self setShowList:NO];
}

- (void)setShowList:(BOOL)b {
    _showList = b;
    if (_showList) {
        self.frame = _newFrame;
    } else {
        self.frame = _oldFrame;
    }
    _listView.hidden = !b;
}

@end