旋转的UIView的框架在iPhone中使用UIPanGesture增加减少

Question

我创建了一个UIView，应用UIPanGestureRecognizer，用一根手指旋转，也用一根手指增加和减少它的框架。

• 旋转视图放在UIView的左下角。
• 调整视图大小放在UIView的右下角。

让我写下其中的一些代码行。

//Rotate Apply with Pan Gesture 
    panRotateGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(rotateViewPanGesture:)];
    [rotateView addGestureRecognizer:panRotateGesture];
    //Resize View Apply with Pan Gesture 
    panResizeGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(resizeTranslate:)];
    [resizeView addGestureRecognizer:panResizeGesture];
    [panRotateGesture requireGestureRecognizerToFail:panResizeGesture]; 

这是使用一根手指的UIPanGesture调整视图大小的方法。

-(void)resizeTranslate:(UIPanGestureRecognizer *)recognizer
{
    if ([recognizer state]== UIGestureRecognizerStateBegan) 
    {
        prevPoint = [recognizer locationInView:self.superview];
        [self setNeedsDisplay];
    }
    else if ([recognizer state] == UIGestureRecognizerStateChanged)
    {
        if (self.frame.size.width < kFixW)
        {
            self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, kFixW, self.frame.size.height);
        }
        if(self.frame.size.height < kFixH)
        {
            self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, self.frame.size.width, kFixH);
        }
        CGPoint point = [recognizer locationInView:self.superview];
        float wChange = 0.0, hChange = 0.0;
        wChange = (point.x - prevPoint.x); //Slow down increment
        hChange = (point.y - prevPoint.y); //Slow down increment 

        self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, self.frame.size.width + (wChange), self.frame.size.height + (hChange));
        NSLog(@"self.frame : %@",NSStringFromCGRect(self.frame));
        prevPoint = [recognizer locationInView:self.superview];
        [self setNeedsDisplay];
    }
    else if ([recognizer state] == UIGestureRecognizerStateEnded)
    {
        prevPoint = [recognizer locationInView:self.superview];
        [self setNeedsDisplay];
    }
}

在这里，如果用于旋转UIView与UIPan手势与一根手指

-(void)rotateViewPanGesture:(UIPanGestureRecognizer *)recognizer
{
    if ([recognizer state] == UIGestureRecognizerStateBegan) 
    {
        deltaAngle = atan2([recognizer locationInView:self].y-self.center.y, [recognizer locationInView:self].x-self.center.x);
        startTransform = self.transform;
    }
    else if ([recognizer state] == UIGestureRecognizerStateChanged) 
    {
        float ang = atan2([recognizer locationInView:self.superview].y - self.center.y, [recognizer locationInView:self.superview].x - self.center.x);
        float angleDiff = deltaAngle - ang;
        self.transform = CGAffineTransformMakeRotation(-angleDiff);
        [self setNeedsDisplay];
    }
    else if ([recognizer state] == UIGestureRecognizerStateEnded)
    {
        float ang = atan2([recognizer locationInView:self.superview].y - self.center.y, [recognizer locationInView:self.superview].x - self.center.x);
        deltaAngle = atan2([recognizer locationInView:self].y-self.center.y, [recognizer locationInView:self].x-self.center.x);
        startTransform = self.transform;
        [self setNeedsDisplay];
    }
}

现在的问题是，调整大小和旋转手势都可以正常工作。

当我使用panResizeGesture调整视图大小时，它可以正常工作，但是如果我应用一次panRotateGesture并且想要应用panResizeGesture，它会退出屏幕并且无法正常工作。

请提出解决此问题的任何想法。

多谢。

Answer 1

文档清楚地说：

**如果转换属性不是标识转换，则此属性的值未定义，因此应忽略。

如果转换属性

包含非标识转换，则帧属性的值未定义，不应修改。在这种情况下，您可以使用 center 属性重新定位视图，并改用 bounds 属性调整大小。

所以，只需在rotateViewPanGesture方法中将self.frame更改为self.bounds

例如

        self.frame = CGRectMake(self.frame.origin.x, self.frame.origin.y, self.frame.size.width, kFixH);

自：

        self.bounds = CGRectMake(self.bounds.origin.x, self.bounds.origin.y, self.bounds.size.width, kFixH);

你的代码将完美地工作。

更新

我附上了使用您的代码的示例项目。 您可以使用此代码答

Answer 2

我知道

这有点晚了，所以也许你已经想通了，但你的问题出在 locationInView 期间：你的代码的一部分。 您正在尝试计算您尝试旋转的实际视图的位置在视图中，而您确实要计算超级视图的位置在视图中。

-(void)rotateViewPanGesture:(UIPanGestureRecognizer *)recognizer{
if ([recognizer state] == UIGestureRecognizerStateBegan) 
{
    deltaAngle = atan2([recognizer locationInView:self.superview].y-self.center.y, [recognizer locationInView:self.superview].x-self.center.x); //here change it to self.superview
    startTransform = self.transform;
}
else if ([recognizer state] == UIGestureRecognizerStateChanged) 
{
    float ang = atan2([recognizer locationInView:self.superview].y - self.center.y, [recognizer locationInView:self.superview].x - self.center.x);
    float angleDiff = deltaAngle - ang;
    self.transform = CGAffineTransformMakeRotation(-angleDiff);
    [self setNeedsDisplay];
}
else if ([recognizer state] == UIGestureRecognizerStateEnded)
{
    float ang = atan2([recognizer locationInView:self.superview].y - self.center.y, [recognizer locationInView:self.superview].x - self.center.x);
    deltaAngle = atan2([recognizer locationInView:self.superview].y-self.center.y, [recognizer locationInView:self.superview].x-self.center.x); //here change it to locationInView:self.superview
    startTransform = self.transform;
    [self setNeedsDisplay];
}}