Ios 如何使uitableview的节标题中的按钮保持选中状态

我有一个按钮，我想改变背景图像，如果它被选中。我这里的代码可以工作，但如果我再次上下滚动，它将变为未选中

- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section {
    UIView *sectionHeader = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.tableView.frame.size.width, 33)];
    UILabel *sectionHeaderLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 0, 100, 30)];
    sectionHeaderLabel.text = [NSString stringWithFormat:@"Section %i",section+1];
    UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(200, 5, 42, 20)];
    [button setBackgroundImage:[UIImage imageNamed:@"unselected_image"] forState:UIControlStateNormal];
    [button setBackgroundImage:[UIImage imageNamed:@"selected_image"] forState:UIControlStateSelected];
    [button addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
    [sectionHeader addSubview:button];
    return sectionHeader;
}

- (void)buttonPressed:(id)sender {
    UIButton *allButton = (UIButton*)sender;
    allButton.selected = !allButton.selected;
}

---

发生这种情况的原因是，当表格上下滚动时，它将再次创建单元格，所以您必须以某种方式管理它，选择或不选择哪个按钮，并再次将选定状态设置为以前在viewForHeaderInSection中选择的按钮。您可以按如下所示进行操作

//Define in header file
NSMutableArray *mutArrSelected;

//Initlise in viewdidload
mutArrSelected = [[NSMutableArray alloc] init];


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

    if(mutArrSelected.count < section)
    {
        [mutArrSelected addObject:[NSNumber numberWithBool:NO]];
    }

    UIView *sectionHeader = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.tableView.frame.size.width, 33)];
    UILabel *sectionHeaderLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 0, 100, 30)];
    sectionHeaderLabel.text = [NSString stringWithFormat:@"Section %i",section+1];
    UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(200, 5, 42, 20)];
    if([[mutArrSelected objectAtIndex:section] boolValue])
    {
        button.selected = YES;
    }
    button.tag = section;
    [button setBackgroundImage:[UIImage imageNamed:@"unselected_image"] forState:UIControlStateNormal];
    [button setBackgroundImage:[UIImage imageNamed:@"selected_image"] forState:UIControlStateSelected];
    [button addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
    [sectionHeader addSubview:button];
    return sectionHeader;
}

- (void)buttonPressed:(id)sender
{
    UIButton *allButton = (UIButton*)sender;
    allButton.selected = !allButton.selected;

    [mutArrSelected removeObjectAtIndex:allButton.tag];
    [mutArrSelected insertObject:[NSNumber numberWithBool:allButton.selected] atIndex:allButton.tag];
}

//在头文件中定义
NSMUTABLEARRY*已选择MUTARRY；
//在viewdidload中初始化
mutArrSelected=[[NSMutableArray alloc]init]；
-（UIView*）表格视图：（UITableView*）表格视图用于标题部分：（NSInteger）部分
{
if（mutArrSelected.count<节）
{
[mutArrSelected addObject:[NSNumber numberWithBool:NO]]；
}
UIView*sectionHeader=[[UIView alloc]initWithFrame:CGRectMake（0,0，self.tableView.frame.size.width，33）]；
UILabel*sectionHeaderLabel=[[UILabel alloc]initWithFrame:CGRectMake（10,0,100,30）]；
sectionHeaderLabel.text=[NSString stringWithFormat:@“Section%i”，Section+1]；
UIButton*button=[[UIButton alloc]initWithFrame:CGRectMake（200,5,42,20）]；
if（[[mutArrSelected objectAtIndex:section]boolValue]）
{
button.selected=是；
}
button.tag=节；
[按钮setBackgroundImage:[UIImage ImageName:@“未选择的_图像”]用于状态：UIControlStateNormal]；
[按钮setBackgroundImage:[UIImage ImageName:@“selected_image”]用于状态：UIControlStateSelected]；
[按钮添加目标：自我操作：@选择器（按钮按下：）用于控制事件：UIControlEventTouchUpInside]；
[节头添加子视图：按钮]；
返回段标题；
}
-（无效）按钮按下：（id）发件人
{
UIButton*allButton=（UIButton*）发送方；
allButton.selected=！allButton.selected；
[mutArrSelected removeObjectAtIndex:allButton.tag]；
[mutArrSelected insertObject:[NSNumber numberWithBool:allButton.selected]atIndex:allButton.tag]；
}

这里发生的事情是，每次视图变为可见时，实际上都会创建一个全新的视图，并重置所有内容。不必这样做，您只需保存视图并每次重复使用相同的视图即可。改为在viewDidLoad中创建视图：

- (void)viewDidLoad
{
    sectionHeader = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.tableView.frame.size.width, 33)];
    UILabel *sectionHeaderLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 0, 100, 30)];
    sectionHeaderLabel.text = [NSString stringWithFormat:@"Section %i",section+1];
    UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(200, 5, 42, 20)];
    [button setBackgroundImage:[UIImage imageNamed:@"unselected_image"] forState:UIControlStateNormal];
    [button setBackgroundImage:[UIImage imageNamed:@"selected_image"] forState:UIControlStateSelected];
    [button addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
    [sectionHeader addSubview:button];
}

viewForHeaderInSection简单地变成：

- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section {
    return sectionHeader;
}

请注意，如果您有多个节，则需要创建节标题视图数组，并根据viewForHeaderInSection中节的值为每个节返回正确的一个节标题视图数组。此数组跟踪照片的名称，无论是否单击

- (void)viewDidLoad
{
    //this array is just an example, loop and add items to the array for the number of sections you want
    //in this example there are 5 sections with 5 images
    imageNameArray = [[NSMutableArray alloc] initWithObjects:@"unselected_image", @"unselected_image", @"unselected_image", @"unselected_image", @"unselected_image", nil];
}

2） 您的

标题视图部分

- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section
{
    UIView *sectionHeader = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.tableView.frame.size.width, 33)];
    UILabel *sectionHeaderLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 0, 100, 30)];
    sectionHeaderLabel.text = [NSString stringWithFormat:@"Section %i",section+1];
    button = [[UIButton alloc] initWithFrame:CGRectMake(200, 5, 42, 20)];
    [button setBackgroundImage:[UIImage imageNamed:[imageNameArray objectAtIndex:section]] forState:UIControlStateNormal];
    [button setTag:section];
    [button addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
    [sectionHeader addSubview:button];
    return sectionHeader;
}

3） 如果按下按钮，则更改阵列中图像的名称

- (void)buttonPressed:(id)sender
{
    UIButton *allButton = (UIButton*)sender;

    [imageNameArray insertObject:@"selected_image" atIndex:[allButton tag]];
    [allButton setBackgroundImage:[UIImage imageNamed:[imageNameArray objectAtIndex:[allButton tag]]] forState:UIControlStateNormal];
}