淡出图像iphone中的动画

可能重复：
iphone褪色的图像

如何在一组图像（图像arrays）中实现淡出动画。 图像将逐一显示。 当我使用下面给出的代码时，它将只显示一个简单的幻灯片放映。

NSArray *imagearray = [NSArray arrayWithObjects: [UIImage imageNamed:@"image1.png"], [UIImage imageNamed:@"imag2.png"],[UIImage imageNamed:@"imag3.png"],[UIImage imageNamed:@"imag4.png"],[UIImage imageNamed:@"imag5.png"],[UIImage imageNamed:@"imag6.png"],[UIImage imageNamed:@"imag7.png"],nil]; imageview.animationImages=imagearray; imageview.animationDuration = 10.00; imageview.animationRepeatCount = 0; [imageview startAnimating]; 

如何实现褪色效果？

Answer 1

请访问此堆栈溢出问题其iphone淡入图像

 - (void)viewDidLoad { imgView.animationImages=[NSArray arrayWithObjects: [UIImage imageNamed:@"lori.png"], [UIImage imageNamed:@"miranda.png"], [UIImage imageNamed:@"taylor.png"], [UIImage imageNamed:@"ingrid.png"], [UIImage imageNamed:@"kasey.png"], [UIImage imageNamed:@"wreckers.png"], nil]; imgView.animationDuration=20.0; imgView.animationRepeatCount=0; [imgView startAnimating]; [self.view addSubview:imgView]; [imgView release]; //The timers time interval is the imageViews animation duration devided by the number of images in the animationImages array. 20/5 = 4 NSTimer *timer = [NSTimer timerWithTimeInterval:4.0 target:self selector:@selector(onTimer) userInfo:nil repeats:YES]; [[NSRunLoop currentRunLoop] addTimer:timer forMode:NSDefaultRunLoopMode]; [timer fire]; [super viewDidLoad]; } //It is important that the animation durations within these animation blocks add up to 4 //(the time interval of the timer). If you change the time interval then the time intervals //in these blocks must also be changed to refelect the amount of time an image is displayed. //Failing to do this will mean your fading animation will go out of phase with the switching of images. -(void)onTimer{ [UIView animateWithDuration:3.0 animations:^{ imgView.alpha = 0.0; }]; [UIView animateWithDuration:1.0 animations:^{ imgView.alpha = 1.0; }]; } 

Answer 2

动画视图的alpha属性：

 [UIView animateWithDuration:5 animations:^{ imageview.alpha = 0; }];