按钮启动的 UIImage 动画

Question

我希望在屏幕上设置一个 50x50 的 UIImage 动画，就像触摸一个按钮时的心电图信号一样。

我正在使用一个测试项目，并且无需按钮即可运行：

@interface IPhoneViewController ()

@end

@implementation IPhoneViewController

- (void)viewDidLoad

{
    [super viewDidLoad];

}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];

}


 -(void)viewDidAppear:(BOOL)animated {
    [super viewDidAppear:animated];

    [UIView animateWithDuration:1.0F animations:^{
    CGPoint oldPosition = self.dot.layer.position;
    CGPoint newPosition = CGPointMake(oldPosition.x + 170, oldPosition.y);
    self.dot.layer.position = newPosition;


    }];

 }



@end

当我在此代码上方添加行- (IBAction)onButtonPressed:(id)sender; { 时，会在-(void)viewDidAppear:(BOOL)animated { 行创建一个错误，指出“使用未声明的标识符'viewDidAppear'”。

首先，如何使用按钮启动动画，其次，我想像 ECG 机器那样以上下运动改变动画的方向，但是如果我在第一个之后添加另一组方向，只执行最后的指令。

 -(void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];

[UIView animateWithDuration:1.0F animations:^{
    CGPoint oldPosition = self.dot.layer.position;
    CGPoint newPosition = CGPointMake(oldPosition.x + 170, oldPosition.y);
    self.dot.layer.position = newPosition;


}];
 [UIView animateWithDuration:1.0F animations:^{
     CGPoint oldPosition = self.dot.layer.position;
     CGPoint newPosition = CGPointMake(oldPosition.x + 10, oldPosition.y - 100);
     self.dot.layer.position = newPosition;


 }];

}

感谢您的帮助。

Answer 1

这是您的解决方案：

- (IBAction)onButtonPressed:(id)sender{
[UIView animateWithDuration:1.0F animations:^{
    CGPoint oldPosition = self.dot.layer.position;
    CGPoint newPosition = CGPointMake(oldPosition.x + 170, oldPosition.y);
    self.dot.layer.position = newPosition;


}completion:^(BOOL finished){
[UIView animateWithDuration:1.0F animations:^{
    CGPoint oldPosition = self.dot.layer.position;
    CGPoint newPosition = CGPointMake(oldPosition.x + 10, oldPosition.y - 100);
    self.dot.layer.position = newPosition;


}];
}];


}

这应该可行，并且您的动画应该一个接一个。