将PinchRecognizer Objective-C代码转换为Swift

我正在尝试将Objective-C代码翻译为Swift，有人可以提供帮助。 我被困在一条线上。

Objective-C的

-(void)pinchDetected:(UIPinchGestureRecognizer *)pinchRecognizer { if([pinchRecognizer state] == UIGestureRecognizerStateBegan) { // Reset the last scale, necessary if there are multiple objects with different scales lastScale = [pinchRecognizer scale]; } if ([pinchRecognizer state] == UIGestureRecognizerStateBegan ||[pinchRecognizer state] == UIGestureRecognizerStateChanged) { ###I NEED TO CONVERT THIS LINE CGFloat currentScale = [[[pinchRecognizer view].layer valueForKeyPath:@"transform.scale"] floatValue]; const CGFloat maxScale = 1.5; const CGFloat minScale = 1.0; CGFloat newScale = 1 - (lastScale - [pinchRecognizer scale]); newScale = MIN(newScale, maxScale / currentScale); newScale = MAX(newScale, minScale / currentScale); thePageViewController.view.transform = CGAffineTransformScale(thePageViewController.view.transform, newScale, newScale); lastScale = [pinchRecognizer scale]; // Store the previous scale factor for the next pinch gesture call } } 

迅速

 func pinchDetected(pinchRecognizer: UIPinchGestureRecognizer) { var lastScale = pinchRecognizer.scale if(pinchRecognizer.state == UIGestureRecognizerState.Began) { // Reset the last scale, necessary if there are multiple objects with different scales lastScale = pinchRecognizer.scale } if (pinchRecognizer.state == UIGestureRecognizerState.Began || pinchRecognizer.state == UIGestureRecognizerState.Changed) { ###HOW DO I CONVERT THIS LINE TO SWIFT? var currentScale: CGFloat = [[[pinchRecognizer.view].layer valueForKeyPath:@"transform.scale"] floatValue]; let maxScale: CGFloat = 1.5; let minScale: CGFloat = 1.0; var newScale: CGFloat = 1 - (lastScale - pinchRecognizer.scale) newScale = min(newScale, maxScale / currentScale); newScale = max(newScale, minScale / currentScale); self.view.transform = CGAffineTransformScale(self.view.transform, newScale, newScale); lastScale = pinchRecognizer.scale // Store the previous scale factor for the next pinch gesture call } } 

Answer 1

您提到转换的行可以像这样完成。 这对我有用。

 var curScale = pinchRecognizer.view!.layer.valueForKeyPath("transform.scale")!.floatValue