自定义手势以增加视图的大小

Question

我如何编写自定义手势以在所有方向（即）原点侧和视图大小上增加视图的大小。

例子：

1. 用户应该在任何一个角落触摸视图。靠近原点侧或查看结束侧。

示例：视图帧大小为(100,100,200,200).，最小触摸距离为距任意一侧 15 像素。

所以，如果用户触摸位置是(X=15,Y=40) in

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event 

方法是指靠近原点的一侧。

如果用户触摸位置是(X=15, Y=190) in，则相同

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

方法表示触摸靠近尺寸边。

我的代码：

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event

{

[super touchesBegan:touches withEvent:event];
if([touches count] != self.touchMinimumCount ||
   [[touches anyObject] tapCount] > self.tapMinimumCount)
{
    self.state = UIGestureRecognizerStateFailed;
    return;
}
self.startPoint = [[touches anyObject] locationInView:self.view];
self.viewFrame = self.view.frame;

if(((self.startPoint.x - self.view.bounds.origin.x) <= self.minimumTouchDistance) ||
   ((self.startPoint.y - self.view.bounds.origin.y) <= self.minimumTouchDistance) ||
   ((ABS(self.startPoint.x - self.view.bounds.size.width)) <= self.minimumTouchDistance) ||
   ((ABS(self.startPoint.y - self.view.bounds.size.height)) <= self.minimumTouchDistance))
{
    self.state = UIGestureRecognizerStatePossible;
    if(((self.startPoint.x - self.view.bounds.origin.x) <= self.minimumTouchDistance) ||
       ((self.startPoint.y - self.view.bounds.origin.y) <= self.minimumTouchDistance) )
    {
        self.currentTouchPosition = touchPositionIsOrigin;
    }
    else if(((ABS(self.startPoint.x - self.view.bounds.size.width)) <= self.minimumTouchDistance) ||
            ((ABS(self.startPoint.y - self.view.bounds.size.height)) <= self.minimumTouchDistance))
    {
        self.currentTouchPosition = touchPositionIsSize;
    }
}
else
{
    self.state = UIGestureRecognizerStateFailed;
}
}

如果触摸仅在触摸距离的一侧，我的手势可能状态设置。

现在我想根据用户手指移动调整视图框架的大小。

1. 如果用户触摸原点侧并向左移动意味着想要改变视图的origin.x并且宽度也想要增加。
2. 如果用户触摸原点侧并向顶部方向移动意味着，想要改变视图的origin.y，宽度也想要增加。
3. 如果用户触摸原点侧并朝正确的方向移动意味着想要改变视图的origin.x。
4. 如果用户触摸原点侧并向底部方向移动意味着要更改视图的origin.y。
5. 如果用户触摸尺寸侧并向左移动意味着想要减小视图的宽度。
6. 如果用户触摸尺寸侧并向顶部方向移动意味着要降低视图的高度。
7. 如果用户触摸尺寸侧并向右移动意味着想要增加视图的宽度。
8. 如果用户触摸尺寸侧并向底部方向移动意味着想要增加视图的高度。

这一切都会根据用户在该视图中移动时的手指而改变。

我的代码：

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event

{

[super touchesMoved:touches withEvent:event];
if(self.state == UIGestureRecognizerStateFailed) return;
direction currentDirection;
CGPoint currentLocation = [[touches anyObject] locationInView:self.view];
if(self.state == UIGestureRecognizerStatePossible ||
   self.state == UIGestureRecognizerStateChanged)
{
    if((currentLocation.x - self.startPoint.x) > 0)
    {
        currentDirection = directionRight;
        self.state = UIGestureRecognizerStateChanged;
        if(self.currentTouchPosition == touchPositionIsOrigin)
        {
            distanceInOriginX = // need to implement. 
            distanceInSizeX = // need to implement. 
        }
        else if(self.currentTouchPosition == touchPositionIsSize)
        {
            distanceInSizeX = // need to implement. 
        }
    }
    else if((currentLocation.x - self.startPoint.x) < 0)
    {
        currentDirection = directionLeft;
        self.state = UIGestureRecognizerStateChanged;
        if(self.currentTouchPosition == touchPositionIsOrigin)
        {
            distanceInOriginX = // need to implement. 
            distanceInSizeX = // need to implement. 
        }
        else if(self.currentTouchPosition == touchPositionIsSize)
        {
            distanceInSizeX = // need to implement. 
        }
    }

    else if((currentLocation.y - self.startPoint.y) >= 0)
    {
        currentDirection = directionBottom;
        self.state = UIGestureRecognizerStateChanged;
        if(self.currentTouchPosition == touchPositionIsOrigin)
        {
            distanceInOriginY = // need to implement. 
            distanceInSizeY = // need to implement.
        }
        else if(self.currentTouchPosition == touchPositionIsSize)
        {
            distanceInSizeY = // need to implement. 
        }
    }
    else if((currentLocation.y - self.startPoint.y) < 0)
    {
        currentDirection = directionTop;
        self.state = UIGestureRecognizerStateChanged;
        if(self.currentTouchPosition == touchPositionIsOrigin)
        {
            distanceInOriginY = // need to implement. 
            distanceInSizeY = // need to implement.
        }
        else if(self.currentTouchPosition == touchPositionIsSize)
        {
            distanceInSizeY = // need to implement. 
        }
    }
    else
    {
        currentDirection = directionUnknown;
    }
    self.originPoint = CGPointMake(distanceInOriginX, distanceInOriginY);
    self.sizePoint = CGPointMake(distanceInSizeX, distanceInSizeY);
}
}

我提到了 // 需要实现。我希望代码在哪里实现我在该点中提到的功能。所以，请帮助我们继续前进。

如果我的方法是错误的，请分享做相同类型手势的最佳方法。

有任何例子也请在这里分享。提前谢谢....

Answer 1

如果要缩放视图的大小，请使用 UIPinchGestureRecognizer。这里给出一个示例代码

UIPinchGestureRecognizer *pinchRecognizer = [[UIPinchGestureRecognizer alloc]initWithTarget:self action:@selector(scale:)];
    pinchRecognizer.delegate = self;
    [self addGestureRecognizer:pinchRecognizer];

处理方法是

#pragma mark - Gesture handling functions



-(void)scale:(UIPinchGestureRecognizer*)recognizer  {

        if ([recognizer state] == UIGestureRecognizerStateBegan) {
            _lastScale = 1.0;
        }

        CGFloat scale = 1.0 - (_lastScale - [recognizer scale]);

        CGAffineTransform currentTransform = self.imgView.transform;
        CGAffineTransform newTransform = CGAffineTransformScale(currentTransform, scale, scale);

        self.imgView.transform = newTransform;

        _lastScale = [recognizer scale];

    }