iphone - 如何重新加载当前的 UIView

Question

我有一个从我的主视图调用的方法，它设置我想在 ScrollView 中显示的图像的图像名称。

 - (void)loadImage:(NSString *)myImageName
    {
        if (myImageName == @"one") {
            imageName = myImageName;
        }
        if (myImageName == @"two") {
            imageName = myImageName;
        }
        if (myImageName == @"three") {
            imageName = myImageName;
        }

        //Reloads view here???
    }

我像这样在我的 viewdidload 方法中加载图像

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    //Create scrollview
    scrollView = [[UIScrollView alloc] initWithFrame:[[UIScreen mainScreen] applicationFrame]];
    scrollView.delegate = self;
    scrollView.bounces = NO;

    //Create scrollviewimage
    if (imageName == @"one") {
        image = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"ha.png"]];
    }
    if (imageName == @"two") {
        image = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"haha.png"]];
    }
    if (imageName == @"three") {
        image = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"hahaha.png"]];
    }



    containerView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 550)];
    //Add subview
    [containerView addSubview:image];
    //initViews
    scrollView.contentSize = containerView.frame.size;
    [scrollView addSubview:containerView];

    //scrolling
    scrollView.minimumZoomScale = 1.0;
    scrollView.maximumZoomScale = 31.0;
    [scrollView setZoomScale:scrollView.minimumZoomScale];

    //highrachy
    [self.view addSubview:scrollView];

}

当我从 tableviewcell 选择的父 View 中设置图像名称时会发生什么我将 nsstring 传递到 loadImage.. 然后加载图像在 viewdidload 中设置名称.. 但是发生的事情是只有第一个选择会做任何事情..所以你总是会看到你选择的第一张图片..所以如果你选择第二张图片，你选择的每隔一张图片都会显示第二张图片..

任何帮助都会很棒。

这是父 View 单元格选择的样子

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    //Sets the back button for the new view that loads (this overrides the usual parentview name with "Back")
    self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Back" style: UIBarButtonItemStyleBordered target:nil action:nil];

    if (!self.detailViewController) {
        self.detailViewController = [[ICDDetailViewController alloc] initWithNibName:@"ICDDetailViewController" bundle:nil];

        if (indexPath.section == 0) {
            _detailViewController.imageName = @"one";
            //        NSLog(@"%@", indexPath);
        }
        if (indexPath.section == 1) {
            _detailViewController.imageName = @"two";
            //        NSLog(@"%@", indexPath);
        }
        if (indexPath.section == 2) {
            _detailViewController.imageName = @"three";
            //        NSLog(@"%@", indexPath);
        }
    }
    [self.navigationController pushViewController:self.detailViewController animated:YES];

}

Answer 1

不要使用 myImageName == @"three"。有一种比较字符串的特殊方法。

试试这个:

if ([myImageName isEqualToString:@"three"]) {
    [image setImage:[UIImage imageNamed:myImageName]];
}

如果有文件扩展名，执行此操作:

NSString *imagePath = [NSString stringWithFormat:@"%@.png",myImageName];
[image setImage:[UIImage imageNamed:imagePath]];

顺便说一句，您仍在发布您在其他问题中的旧代码。您将 detailView 保留在原始类中，而不是释放和创建新实例。取出 if (!detailView) 语句。

更新:唯一的其他选择是从大的 if() block 中取出赋值。

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    //Sets the back button for the new view that loads (this overrides the usual parentview name with "Back")
    self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Back" style: UIBarButtonItemStyleBordered target:nil action:nil];

    if (!self.detailViewController) {
        self.detailViewController = [[ICDDetailViewController alloc] initWithNibName:@"ICDDetailViewController" bundle:nil];


    //MY CHANGES HERE:
    //If you left these if () statements inside the original code, they would never
    //fire if the detailView was already instantiated once.  Does this make sense?
    }  // <--- moved the bracket up here
        if (indexPath.section == 0) {
            _detailViewController.imageName = @"one";
            //        NSLog(@"%@", indexPath);
        }
        if (indexPath.section == 1) {
            _detailViewController.imageName = @"two";
            //        NSLog(@"%@", indexPath);
        }
        if (indexPath.section == 2) {
            _detailViewController.imageName = @"three";
            //        NSLog(@"%@", indexPath);
        }
    //}  <--- commented this one out
    [self.navigationController pushViewController:self.detailViewController animated:YES];

}

唯一的另一种方式是:

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    //Sets the back button for the new view that loads (this overrides the usual parentview name with "Back")
    self.navigationItem.backBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"Back" style: UIBarButtonItemStyleBordered target:nil action:nil];
    //commented out the next line, don't need to check to see if it's already present
    //just create a new instance to push on the stack
    //if (!self.detailViewController) {
        self.detailViewController = [[ICDDetailViewController alloc] initWithNibName:@"ICDDetailViewController" bundle:nil];

        if (indexPath.section == 0) {
            _detailViewController.imageName = @"one";
            //        NSLog(@"%@", indexPath);
        }
        if (indexPath.section == 1) {
            _detailViewController.imageName = @"two";
            //        NSLog(@"%@", indexPath);
        }
        if (indexPath.section == 2) {
            _detailViewController.imageName = @"three";
            //        NSLog(@"%@", indexPath);
        }
    //} <--- get rid of this bracket since the original if () was commented out
    [self.navigationController pushViewController:self.detailViewController animated:YES];

}