iOS：通过捏缩放UITextView？ [英] iOS: Scaling UITextView with pinching?

问题描述

我有兴趣创建 UITextView ，它在键入文本时动态扩展，并在用户捏住屏幕时进行缩放（可在TinyPost中找到相似的行为）。

I'm interested in creating UITextView that is expanding dynamically while typing the text, and scaling as the user pinches the screen(Similar behaviour can be found in TinyPost).

当你输入（没有捏）时，textView扩展正常。当你只是捏（没有打字）工作正常，但当你捏然后键入，里面的文字被削减。

When you just type (without pinching) the textView expands fine. When you just pinch (without typing) is works fine, but when you pinch and then type, the text inside gets cut.

这是我的代码：

UIPinchGestureRecognizer *pinchGestRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(scaleTextView:)];
        pinchGestRecognizer.delegate = self;
        [bgFrameImageView addGestureRecognizer:pinchGestRecognizer];

    - (void)scaleTextView:(UIPinchGestureRecognizer *)pinchGestRecognizer{
        createTextView.transform = CGAffineTransformScale(createTextView.transform, pinchGestRecognizer.scale, pinchGestRecognizer.scale);

        pinchGestRecognizer.scale = 1;        
    }

    - (void)textViewDidChange:(UITextView *)textView{

        CGSize textSize = textView.contentSize;

        textView.frame = CGRectMake(CGRectGetMinX(textView.frame), CGRectGetMinY(textView.frame), textSize.width, textSize.height); //update the size of the textView  
    }

你怎么看？

推荐答案

尝试：

- (void)scaleTextView:(UIPinchGestureRecognizer *)pinchGestRecognizer{
     CGFloat scale = pinchGestRecognizer.scale;

    createTextView.font = [UIFont fontWithName:createTextView.font.fontName size:createTextView.font.pointSize*scale];

    [self textViewDidChange:createTextView];       
}

它基本上会缩放字体大小，然后使用您的代码重新计算内容大小textViewDidChange。

It basically scales the font size and then recalculates the content size using your code in textViewDidChange.

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