ios - 如何获取屏幕的结束CGPoint？

Question

有没有办法找到屏幕的端点？假设屏幕大小为 (100x100)，中点为 (50,)，起点为 (0,)，终点为 (100,)。我可以根据设备屏幕尺寸进行硬编码以获得终点，但基于假设，这将是一项过多的工作。

我正在制作一个基于 UIBezierPath 的自定义 UIView 动画。

这是我正在尝试做的事情:

如您所见，动画在到达某个点后停止。我希望这一点成为屏幕的末尾，以便 UIView 覆盖整个 屏幕。为了更清楚，我将 UIView 拖到 A 点，然后它动画到 B 点(终点，所以 B>A)

我不确定如何计算 B，所以当我将 UIView 拖到 A 时，它会动画到屏幕的末尾(屏幕的端点)。

为了更好的理解下面的代码:

- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint touchLocation = [touch locationInView:self.dragView];

 if (touchLocation.x<250) {

        if (!startBackSlide) {
             _circleDragView.touchdragPoint=touchLocation.y;
            _circleDragView.dragToPoint=CGPointMake(touchLocation.x+40, touchLocation.y);
            [_circleDragView setNeedsDisplay];
            _savedPoint=touchLocation;
        }else{

            //move the top and bot points backwards along with slide
            [self animateCOmpleteBezier:touchLocation];

            _circleDragView.touchdragPoint=touchLocation.y;
            _circleDragView.dragToPoint=CGPointMake(touchLocation.x+54, touchLocation.y);
            [_circleDragView setNeedsDisplay];
            _savedPoint=touchLocation;

            if (touchLocation.x<20) {
                startBackSlide=NO;
                snapped=YES;
            }
        }

    }

    if (touchLocation.x>=250) {

        if (snapped) {
            snapped=NO;
            //move the top and bottom points to the specified point(In this case the end point)
        }

    }

}

-(void)animateCOmpleteBezier:(CGPoint) value{

    [UIView animateWithDuration:0.01 delay:0  options:UIViewAnimationOptionCurveEaseOut animations:^{
        _circleDragView.topWidthPoint=value.x-10;
        _circleDragView.botWidthPoint=value.x-10;
        [_circleDragView setNeedsDisplay];

    } completion:^(BOOL finished) {

    }];


}

Answer 1

屏幕的端点等于它的宽度和高度:

CGSize screenSize = [UIScreen mainScreen].bounds.size;
CGPoint endPoint = CGPointMake(screenSize.width, screenSize.height);

https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIScreen_Class/#//apple_ref/occ/instp/UIScreen/bounds