Question

我有100张图片（a400e3x_0.png，.....，a400e3x_98.png，a400e3x_99.png）。这些图像根据UIImageView上的滑动而变化，就像用户可以控制的动画一样。问题是当用户停止平移然后再次启动时，动画将返回到图像0.我需要在用户停止平移时保存位置，我可以这样做。但是当我添加它时，添加总是在那里。示例：我在图像16处停止平移，然后从16开始，当（curX％100）为零时，它仍然会添加16。你可以帮我解决这个问题。

- (IBAction)PanGesAction:(id)sender
{
 CGPoint translation = [_PanGes translationInView:self.view];
 int curX = (int)translation.x;
 addition = (curX%100)+Savedif;

 NSLog(@"%d", addition);

 [_ImageV2 setImage:[UIImage imageNamed:[NSString stringWithFormat:@"a400e3x_%d.png", addition]]];


    if (_PanGes.state == UIGestureRecognizerStateEnded)
    {
        NSLog(@"End");
        Savedif = addition;
        //When user end

    }

    if (_PanGes.state == UIGestureRecognizerStateBegan)
    {
        NSLog(@"Began");
         //When user begin

    }
}

Answer 1

当一个新手势开始时，您有机会编辑它将要发送给您的值，因此我们可以将您的起始值转移到手势并保持简单：

- (IBAction)PanGesAction:(id)sender
{
    if (_PanGes.state == UIGestureRecognizerStateBegan)
    {
        NSLog(@"Began");
        //When user begin
        [_PanGes setTranslation:(CGPoint){Savedif, 0} inView:self.view];
        Savedif = 0;
    }

    CGPoint translation = [_PanGes translationInView:self.view];
    int curX = (int)translation.x;
    addition = (curX%100);

    NSLog(@"%d", addition);

    [_ImageV2 setImage:[UIImage imageNamed:[NSString stringWithFormat:@"a400e3x_%d.png", addition]]];


    if (_PanGes.state == UIGestureRecognizerStateEnded)
    {
        NSLog(@"End");
        Savedif = addition;
        //When user end
    }
}

Answer 2

有一种方法，你不必保存任何东西，

在transform，

中引入UIView属性

试试这段代码：

- (void)handlePanGesture:(UIPanGestureRecognizer *)gesture
{
    UIView *imageView = gesture.view;
    if (gesture.state == UIGestureRecognizerStateChanged) {
        CGPoint transition = [gesture translationInView:gesture.view];
        imageView.transform = CGAffineTransformMakeTranslation(imageView.transform.tx + transition.x, imageView.transform.tx + transition.y);
        [gesture setTranslation:CGPointZero inView:gesture.view];
    }
    else if (gesture.state == UIGestureRecognizerStateEnded) {
        imageView.center = CGPointMake(imageView.center.x + imageView.transform.tx, imageView.center.y + imageView.transform.ty);
        imageView.transform = CGAffineTransformIdentity;
    }
}

imageView的位置始终为：

imageView.center.x+image.transform.tx
imageView.center.y+image.transform.ty

你可以据此采取行动。

具有平移手势算法的图像序列

2 个答案: