如何使用 uibuttons 为图像设置动画

Question

我有三个名为 1,2 和 3 的 uibuttons，在这些按钮的底部我有一个箭头图像，指示当前按下的按钮。 我希望当我按下任何按钮时，箭头开始动画并在按下的按钮底部滑动。

Answer 1

• (void)setImage:(UIImage *)image forState:(UIControlState)state;

并从中选择 UIControlState

enum {
UIControlStateNormal       = 0,                       
UIControlStateHighlighted  = 1 << 0,                  // used when UIControl isHighlighted is set
UIControlStateDisabled     = 1 << 1,
UIControlStateSelected     = 1 << 2,                  // flag usable by app (see below)
UIControlStateApplication  = 0x00FF0000,              // additional flags available for application use
UIControlStateReserved     = 0xFF000000               // flags reserved for internal framework use
};
typedef NSUInteger UIControlState;

Answer 2

将所有按钮与一个方法挂钩，或者在响应每个按钮单击的方法中也调用此方法。

- (IBAction)buttonTapped:(UIButton *)sender;
{
    CGPoint center = self.indicator.center;
    center.x = sender.center.x;

    [UIView animateWithDuration:0.25f
                     animations:^{
                         self.indicator.center = center;
                     }];
}

Answer 3

在您的按钮按下方法中执行以下操作：

// For Button 1
- (IBAction)pressedButton1:(id)sender{

        // Create an animation lasting 1 second
        [UIView beginAnimations:nil context:nil];
        [UIView setAnimationDuration:1.00];
        [UIView setAnimationDelegate:self];

        // Set your arrow image view's center x property to that of the button
        myArrowImageView.center = CGPointMake(myButton1.center.x, myArrowImageView.center.y);

        [UIView commitAnimations];

}

// For Button 2
- (IBAction)pressedButton2:(id)sender{

    // Create an animation lasting 1 second
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:1.00];
    [UIView setAnimationDelegate:self];

    // Set your arrow image view's center x property to that of the 2nd button
    myArrowImageView.center = CGPointMake(myButton2.center.x, myArrowImageView.center.y);

    [UIView commitAnimations];

}

// For Button 3
- (IBAction)pressedButton3:(id)sender{

    // Create an animation lasting 1 second
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDuration:1.00];
    [UIView setAnimationDelegate:self];

    // Set your arrow image view's center x property to that of the 3rd button
    myArrowImageView.center = CGPointMake(myButton3.center.x, myArrowImageView.center.y);

    [UIView commitAnimations];

}

附：当您提出问题时，也发布一些源代码总是好的。这有助于人们为您提供更好的答案。