Question

我有一个标签，弹出显示我的应用程序中的点。我使用以下代码使标签的规模变大，然后变小。我还想将颜色从紫色变为绿色。有人能指出我实现这个目标的资源吗？

mLabel.textColor = [UIColor purpleColor];

 [UIView beginAnimations:nil context:NULL];
 [UIView setAnimationDuration:1.0];
 [UIView setAnimationDelegate:self];
 mLabel.transform = CGAffineTransformMakeScale(1.5,1.5);
 [UIView setAnimationRepeatCount:1];
 mLabel.transform = CGAffineTransformMakeScale(0.5,0.5);
 mLabel.textColor = [UIColor greenColor];
 [UIView commitAnimations];

Answer 1

您可以使用iOS 4.0的视图转换方法执行此操作：

[UIView transitionWithView:statusLabel duration:0.25 options:UIViewAnimationOptionTransitionCrossDissolve animations:^{
    [statusLabel setTextColor:[UIColor whiteColor]];
    [statusLabel setShadowColor:[UIColor blackColor]];
} completion:nil];

Answer 2

不幸的是，UIView动画的颜色没有动画效果。 this question的答案在不使用核心动画的情况下提供了一些很好的解决方法。

如果你不介意使用CATextLayer而不是UILabel，那么颜色（以及你的例子中的缩放）可以像这样动画：

#import <QuartzCore/QuartzCore.h>
//Also need to add QuartzCore framework to project (as well as the import).
//
-(void)animateTextLayer {

CGFloat animationDuration = 5;

CATextLayer *textLayer = [CATextLayer layer];
[textLayer setString:@"Hello World"];
[textLayer setForegroundColor:[UIColor purpleColor].CGColor];
[textLayer setFontSize:30];
[textLayer setFrame:CGRectMake(20, 200, 300, 40)];
[[self.view layer] addSublayer:textLayer];

CABasicAnimation *colorAnimation = [CABasicAnimation 
                                     animationWithKeyPath:@"foregroundColor"];
colorAnimation.duration = animationDuration;
colorAnimation.fillMode = kCAFillModeForwards;
colorAnimation.removedOnCompletion = NO;
colorAnimation.fromValue = (id)[UIColor purpleColor].CGColor;
colorAnimation.toValue = (id)[UIColor greenColor].CGColor;
colorAnimation.timingFunction = [CAMediaTimingFunction 
                                 functionWithName:kCAMediaTimingFunctionLinear];

CAKeyframeAnimation *scaleAnimation = [CAKeyframeAnimation 
                                        animationWithKeyPath:@"transform"];
NSArray *scaleValues = [NSArray arrayWithObjects:
    [NSValue valueWithCATransform3D:CATransform3DScale(textLayer.transform, 1, 1, 1)],
    [NSValue valueWithCATransform3D:CATransform3DScale(textLayer.transform, 1.5, 1.5, 1)],
    [NSValue valueWithCATransform3D:CATransform3DScale(textLayer.transform, 0.5, 0.5, 1)], nil];
[scaleAnimation setValues:scaleValues]; 
scaleAnimation.fillMode = kCAFillModeForwards;
scaleAnimation.removedOnCompletion = NO;

CAAnimationGroup *animationGroup = [CAAnimationGroup animation];
animationGroup.duration = animationDuration;
animationGroup.timingFunction = [CAMediaTimingFunction 
                                functionWithName:kCAMediaTimingFunctionLinear];
animationGroup.fillMode = kCAFillModeForwards;
animationGroup.removedOnCompletion = NO;
animationGroup.animations = 
        [NSArray arrayWithObjects:colorAnimation, scaleAnimation, nil];

[textLayer addAnimation:animationGroup forKey:@"animateColorAndScale"];
}

Answer 3

textColor不可动画的原因是UILabel使用常规CALayer而不是CATextLayer。

为了使textColor可以生成动画（以及文本，字体等），我们可以将UILabel子类化并使其使用CATextLayer。

这是相当多的工作，但幸运的是我已经做到了： - ）

您可以在article

中找到完整的解释+ UILabel的直接替代开源替代品

Answer 4

如果您需要使用为突出显示或选定状态指定的IB颜色，并希望使用淡出效果为颜色更改设置动画，则可以使用下一个代码：

<强>夫特：

@IBAction func buttonAction(sender: AnyObject) {

    // Set selected to leave same color as for highlighted
    // (default=black, highlighted=red, selected=red)
    self.openAllButton.selected = true

    // Delay before the color change animation 
    let delayInSeconds = 0.1;
    let delay = delayInSeconds * Double(NSEC_PER_SEC)
    let popTime = dispatch_time(DISPATCH_TIME_NOW, Int64(delay));
    dispatch_after(popTime, dispatch_get_main_queue(), {
        // Animate color change
        UIView.transitionWithView(self.openAllButton, duration: 1.0, options: UIViewAnimationOptions.TransitionCrossDissolve, animations: { () -> Void in
            self.openAllButton.selected = false          // selected->default
            }) { (v:Bool) -> Void in
        }
    });

}

Answer 5

这行代码适合我。确保将选项设置为交叉溶解夫特：

static func animationButtonTextColor(button : UIButton, toColor : UIColor, duration : NSTimeInterval) {
    UIView.transitionWithView(button, duration: duration, options: UIViewAnimationOptions.TransitionCrossDissolve, animations: {
      button.setTitleColor(toColor, forState: .Normal)
    }, completion: nil)
  }

Answer 6

在致电commitAnimations之前添加此内容：

[UIView setAnimationTransition:UIViewAnimationTransitionNone forView:mLabel cache:YES];

Answer 7

试试这个：

[UIView animateWithDuration:0.5 animations:^{

    label.alpha=0.3;


}completion:^(BOOL finished)
 {
    label.backgroundcolor=[uicolor purplecolor]; 


     [UIView animateWithDuration:0.5 animations:^{

         label.alpha=1.0;

     }completion:^(BOOL finished)
      {

      }];

 }];

iPad：动画UILabels变色

7 个答案: