iphone - 转换矩形 :toView: works different on iPad retina and iPad 2

Question

我的这段代码在 iPad2 上完美运行，但在 Retina iPad 上缩放错误。

我在两台 iPad 上都执行了该应用程序，但行为完全不同。在 Retina iPad 上，图像返回到原始位置并且不会发生转换。

代码采用一组 View ，将它们添加到临时 View ，调整临时 View 的大小，然后将这些 View 添加回去，这样我就可以同时调整所有 View 的大小。

- (IBAction)scaleParts:(UIPinchGestureRecognizer *)sender {
if (sender.state == UIGestureRecognizerStateBegan) {
    self.tempCanvasView = [[UIView alloc] initWithFrame:self.canvas.bounds];
    self.tempCanvasView.backgroundColor = [UIColor redColor];
    for (UIView *view in [self.canvas subviews]) {
        CGRect currentFrame = view.bounds;
        CGRect newFrame = [view convertRect:currentFrame toView:self.tempCanvasView];
        view.bounds = newFrame;
        [self.tempCanvasView addSubview:view];
    }
    [self.canvas addSubview:self.tempCanvasView];
} else if (sender.state == UIGestureRecognizerStateChanged) {
    self.tempCanvasView.transform = CGAffineTransformScale(self.tempCanvasView.transform, sender.scale, sender.scale);
    sender.scale = 1.0;
} else if (sender.state == UIGestureRecognizerStateEnded) {
    for (UIView *view in [self.tempCanvasView subviews]) {
        CGRect currentFrame = view.bounds;
        CGRect newFrame = [view convertRect:currentFrame toView:self.canvas];
        view.frame = newFrame;
        [self.canvas addSubview:view];
    }
    [self.tempCanvasView removeFromSuperview];
    self.tempCanvasView = nil;
}
}

Answer 1

也许您需要检测应用程序使用的屏幕类型(iPad 的比例=1，iPadRetina 的比例=2)。

CGFloat scale = [[UIScreen mainScreen] scale];

在那之后..

 if (scale==1) {
        //code from above
    } else {
        //code from above with small modification
    }