Question

我正在使用touchesMoved方法让图像沿着屏幕底部“跟随”某人的手指。因此图像将遵循手指的x位置，但它忽略y位置并垂直固定在底部（但不是水平固定）。有什么办法可以实现吗？

这是我的代码：

- (void)viewDidLoad
{
    [super viewDidLoad];

    // create basket image that will be shown on the screen
    basketView = [[UIImageView alloc]
    initWithImage:[UIImage imageNamed:@"bucket.png"]];
    basketView.frame = CGRectMake(130.0, 412.0, 50.0, 50.0);
    [self.view addSubview:basketView];
}


-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    // get current touch location
    UITouch *touch = [[event touchesForView:self.view] anyObject];
    CGPoint point = [touch locationInView:self.view];
    // update location of the image
    basketView.center = point;
}

Answer 1

保持y位置，改变x

basketView.center = CGPointMake(point.x, basketView.center.y);

Answer 2

在touchesMoved中执行此操作

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    // get current touch location
    UITouch *touch = [[event touchesForView:self.view] anyObject];
    CGPoint point = [touch locationInView:self.view];
    // update location of the image
    basketView.center = CGPointMake(point.x,basketView.center.y);
}

Answer 3

执行以下操作......

-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
    {
        // get current touch location
        UITouch *touch = [[event touchesForView:self.view] anyObject];
        CGPoint point = [touch locationInView:self.view];

        point.y=basketView.center.y;   //Fix 'y' of basket
        // update location of the image
        basketView.center = point;
    }

让图像沿着x轴跟随手指，但是具有固定的y坐标

3 个答案: