Question

在我的项目中，我正在UIImageView上进行以下活动 1.）旋转它 2.）移动它 3.）缩放它。我的项目还有一个名为“New”的按钮，它将重置app.my的所有设置问题是，如果我旋转图像并单击新按钮，UIImageVIew的设置不会改变。可以有人有任何想法。谢谢提前

-(void)rotate:(id)sender {

    if([(UIRotationGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) {

        lastRotation = 0.0;
        return;
    }

    CGFloat rotation = 0.0 - (lastRotation - [(UIRotationGestureRecognizer*)sender rotation]);

    CGAffineTransform oldTransform = [(UIPinchGestureRecognizer*)sender view].transform;
    CGAffineTransform newTransform = CGAffineTransformRotate(oldTransform,rotation);

    [[(UIRotationGestureRecognizer*)sender view] setTransform:newTransform];

    lastRotation = [(UIRotationGestureRecognizer*)sender rotation];
}

以上我用于轮换的代码。

Answer 1

如果imageView是您的UIImageView对象，则重置transform属性已完成，

imageView.transform = CGAffineTransformIdentity;

此外，如果您未在其他地方使用rotate:，则可以稍微缩短lastRotation方法。

-(void)rotate:(UIRotationGestureRecognizer *)gesture {
    UIView * view = gesture.view;
    view.transform = CGAffineTransformRotate(view.transform, gesture.rotation);
    gesture.rotation = 0;
}

Answer 2

对于那些感兴趣的人来说，另一个实用的Swift示例，我能够构建Deepak的旋转图像示例，然后通过使用UIImageView的扩展来反转旋转

extension UIImageView {

    func rotateCounterClockwise() {
        UIView.animateWithDuration(0.3, animations: {
           self.transform = CGAffineTransformMakeRotation(CGFloat(-M_PI))
    })
 }

    func rotateToOriginal() {
        UIView.animateWithDuration(0.3, animations: { 
           self.transform = CGAffineTransformIdentity
    })
 }

}

如何重置UIImageView转换属性

2 个答案: