当我在 ios 中展开和折叠 TableList 单元格时如何更改 UILabel 文本颜色

Posted 2023-03-08

【中文标题】当我在 ios 中展开和折叠 TableList 单元格时如何更改 UILabel 文本颜色

【英文标题】：How to change UILabel text-color when i expand and Collapse the TableList cells in ios

【发布时间】：2015-12-14 08:42:57

【问题描述】：

我是 ios 新手，我创建了一个 Expandable-ListView，这里我的主要要求是当我展开单元格时，我想将 UILabel textcolor 更改为“红色”颜色，其余所有单元格 UILabel textcolors 必须像下面的图片一样是“橙色”，当我折叠展开的单元格时，该单元格的UILabel textcolor 必须是“橙色”。

为此，我尝试了下面的代码，但是当我折叠单元格时，文本颜色没有像“橙色”那样改变，请帮助我。

我的代码：

.h 文件：-

#import <UIKit/UIKit.h>
@interface ViewController : UIViewController<UITableViewDataSource,UITableViewDelegate>

    NSMutableArray  *arrayForBool;
    NSArray *sectionTitleArray;


@property (weak, nonatomic) IBOutlet UITableView *expandableTableView;

@end

.m 文件：-

#import "ViewController.h"

@interface ViewController ()

    UILabel *viewLabel;
    BOOL collapsed;
    NSInteger collapsedSection;


@end

@implementation ViewController

- (void)viewDidLoad

    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    [self initialization];


#pragma  mark - Initialization

-(void)initialization

    arrayForBool=[[NSMutableArray alloc]init];
    sectionTitleArray=[[NSArray alloc]initWithObjects:
                       @"Apple",
                       @"Strawberry",
                       @"Grapes",
                       @"Orange",
                       @"Banana",
                       @"Papaya",
                       @"Guava",
                       @"pineapple",
                       nil];

    for (int i=0; i<[sectionTitleArray count]; i++) 
        [arrayForBool addObject:[NSNumber numberWithBool:NO]];
    



#pragma mark -
#pragma mark TableView DataSource and Delegate Methods

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section


    if ([[arrayForBool objectAtIndex:section] boolValue]) 
        return section+2;
    
    else
    return 0;



- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath



    static NSString *cellid=@"hello";
    UITableViewCell *cell=[tableView dequeueReusableCellWithIdentifier:cellid];
    if (cell==nil) 
        cell=[[UITableViewCell alloc]initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:cellid];
    
        BOOL manyCells  = [[arrayForBool objectAtIndex:indexPath.section] boolValue];

             /********** If the section supposed to be closed *******************/
        if(!manyCells)
        
            cell.backgroundColor=[UIColor clearColor];

            cell.textLabel.text=@"";
        
             /********** If the section supposed to be Opened *******************/
        else
        
            cell.textLabel.text=[NSString stringWithFormat:@"%@ %d",[sectionTitleArray objectAtIndex:indexPath.section],indexPath.row+1];
            cell.textLabel.font=[UIFont systemFontOfSize:15.0f];
            cell.backgroundColor=[UIColor whiteColor];
            cell.imageView.image=[UIImage imageNamed:@"point.png"];
            cell.selectionStyle=UITableViewCellSelectionStyleNone ;
        
    cell.textLabel.textColor=[UIColor blackColor];

                  /********** Add a custom Separator with cell *******************/
    UIView* separatorLineView = [[UIView alloc] initWithFrame:CGRectMake(15, 40, _expandableTableView.frame.size.width-15, 1)];
    separatorLineView.backgroundColor = [UIColor blackColor];
    [cell.contentView addSubview:separatorLineView];

    return cell;


- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView

    return [sectionTitleArray count];


- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath


    /*************** Close the section, once the data is selected ***********************************/
    [arrayForBool replaceObjectAtIndex:indexPath.section withObject:[NSNumber numberWithBool:NO]];

     [_expandableTableView reloadSections:[NSIndexSet indexSetWithIndex:indexPath.section] withRowAnimation:UITableViewRowAnimationAutomatic];




- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath

    if ([[arrayForBool objectAtIndex:indexPath.section] boolValue]) 
        return 40;
    
    return 0;



- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section

    return 40;


#pragma mark - Creating View for TableView Section

- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section

    UIView *sectionView=[[UIView alloc]initWithFrame:CGRectMake(0, 0, 280,40)];
    sectionView.tag=section;

    for (id subview in sectionView.subviews) 
        if ([subview isKindOfClass:[UIImageView class]]) 
            [subview removeFromSuperview];
         else if ([subview isKindOfClass:[UILabel class]]) 
            [subview removeFromSuperview];
        
    

    viewLabel=[[UILabel alloc]initWithFrame:CGRectMake(10, 0, _expandableTableView.frame.size.width-10, 40)];
    viewLabel.font=[UIFont systemFontOfSize:15];
    viewLabel.text=[NSString stringWithFormat:@"List of %@",[sectionTitleArray objectAtIndex:section]];
    [sectionView addSubview:viewLabel];

    if (collapsedSection ==  section) 

        viewLabel.textColor = [UIColor redColor];
    else

        viewLabel.textColor = [UIColor orangeColor];
    

    /********** Add a custom Separator with Section view *******************/

    UIView* separatorLineView = [[UIView alloc] initWithFrame:CGRectMake(15, 40, _expandableTableView.frame.size.width-15, 1)];
    separatorLineView.backgroundColor = [UIColor blackColor];
    [sectionView addSubview:separatorLineView];

    /********** Add UITapGestureRecognizer to SectionView   **************/

    UITapGestureRecognizer  *headerTapped   = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(sectionHeaderTapped:)];
    [sectionView addGestureRecognizer:headerTapped];

    return  sectionView;

#pragma mark - Table header gesture tapped

- (void)sectionHeaderTapped:(UITapGestureRecognizer *)gestureRecognizer


    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:gestureRecognizer.view.tag];

    collapsedSection = gestureRecognizer.view.tag;

    if (indexPath.row == 0) 

       collapsed  = [[arrayForBool objectAtIndex:indexPath.section] boolValue];

        for (int i=0; i<[sectionTitleArray count]; i++) 

            if (indexPath.section==i) 

                [arrayForBool replaceObjectAtIndex:i withObject:[NSNumber numberWithBool:!collapsed]];
            
        

        [_expandableTableView reloadSections:[NSIndexSet indexSetWithIndex:gestureRecognizer.view.tag] withRowAnimation:UITableViewRowAnimationAutomatic];
    


@end

【问题讨论】：

你想改变 Apple 1 文字的颜色吗？ @Krish

no @jay Bhalani 标题颜色（如上面的 Apple 列表，草莓列表）我想在单元格展开时将颜色更改为“红色”，当单元格折叠时颜色必须为“橙色”

希望您能理解我的要求

它完全取决于你的实现方式。

所以当你折叠单元格时你的问题是什么？ expand 与红色文本完美搭配？我是对还是错。

【参考方案1】：

只需要替换以下行：

if(collapsedSection ==  section) 

与

if ([[arrayForBool objectAtIndex:section] boolValue])