Question

我知道如果有一个名为Default.png的文件，它会自动显示图像。但是，我希望在它显示期间更改图像。仅供参考，我有2张图片Default.png和default2.png。我想在show Default.png之后显示default2.png。我尝试了跟随代码，但它没有用。我该怎么办？

-(BOOL) application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{

//..................................................................
//self.window bullabulla~

[self performSelectorOnMainThread:@selector(showIntro2View) withObject:nil waitUntilDone:YES];
//[self showIntro2View];  //also tried this, but not work.

[self.window addsubview:tabbarController];
[self.window makeKeyAndVisible];
}
-(void) showIntro2View {
UIImageView *intro2 = [[UIImageView alloc]initwithframe:cgrectmake(0,0,320,460)];
intro2.image = [UIImage imagenamed:@"default2.png"];
[self.window addSubview:intro2];
[self.window bringSubviewToFront:intro2];
[NSThread sleepfortimeinterval:2];
}

Answer 1

在APP DELEGATE中。这样的事情应该可以胜任：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    
    UIImageView *imageView = [[[UIImageView alloc] initWithFrame:self.window.bounds] autorelease];
    UIImage *image = [UIImage imageNamed:@"NAMEOFYOURSPLASHSCREEN.png"];
    imageView.image = image;
    [self.window addSubview:imageView];
    [self.window makeKeyAndVisible];
    [self performSelector:@selector(remove1stSplash:) withObject:imageView afterDelay:5];
    return YES;
}

- (void)remove1stSplash:(UIImageView *)1stView {
    UIImageView *imageView = ...
    [self.window addSubview:imageView];
    [self performSelector:@selector(remove2ndSplash:) withObject:imageView afterDelay:5];
    [1stView removeFromSuperView];
}

- (void)remove2ndSplash:(UIImageView *)2ndView {
    [self.window addSubview:.....
    [2ndView removeFromSuperView];
}

修改

示例项目的链接： Two Splash Screen display in iphone

Answer 2

您可能知道，您对Default img的显示时间没有实际影响。但是你知道什么时候显示和隐藏。它仅显示，当应用程序第一次运行时，应用程序不在后台或在一段时间未使用后终止。

第一个被调用的View Controller应该实现viewWillAppear，因为它类似于默认图像隐藏之前调用的最后一个方法。所有内容都已加载，您可以立即将子视图添加到主窗口。

我会用showOverrideDefaultImage和hideOverrideDefaultImage这两种不同的方法来做。在show方法中，您将自己的View添加到appDelegate窗口并触发

[self performSelector:@selector(hideOverrideDefaultImage) withObject:nil afterDelay:2];

在隐藏方法中，只需从superview中删除您的视图即可。因此，您必须有一个指向此对象的有效指针。

就是这样。不要使用NSThread。

Answer 3

这样做：

 -(void) showIntro2View 
{
  UIImageView *intro2 = [[UIImageView alloc]initwithframe:cgrectmake(0,0,320,460)];
  intro2.image = [UIImage imagenamed:@"default2.png"];
  intro2.animationImages = [NSArray arrayWithObjects:    
                           [UIImage imageNamed:@"Default.png"],
                           [UIImage imageNamed:@"default2.png"], nil];
  intro2.animationDuration = 2.0f;
  intro2.animationRepeatCount = 0;
  [intro2 startAnimating];

  [self.window addSubview:intro2];
  [self.window bringSubviewToFront:intro2];
  [NSThread sleepfortimeinterval:2];
}

如何在应用程序启动时显示2个介绍视图？

3 个答案: