Question

我正在尝试记录触摸的位置。以下是我的代码。据我了解，在最左上角的触摸将给我一个（0,0）的位置，并且非常右下角将是（768,1024）假设我正在拿着iPad的肖像。但是，左上角的值为（-6，-18），右下角的值为（761,1003）。看起来坐标会以某种方式移动。一段self.bounds确实给了我{{0,0}，{768,1024}}。谁可以给我解释一下这个？我想得到界限{{0,0}，{768,1024}}之间的x和y值。非常感谢你提前。

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
     CGRect bounds = [self bounds]; 
     NSLog(@"frame: %@", NSStringFromCGRect(bounds)); // this value was traced as frame: {{0, 0}, {768, 1024}}

     UITouch* touch = [[event touchesForView:self] anyObject]; 
     location = [touch locationInView:self];
     NSLog(@"Location: %@", NSStringFromCGPoint(location));

}


- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
     CGRect bounds = [self bounds]; 

     UITouch* touch = [[event touchesForView:self] anyObject]; 
     location = [touch locationInView:self];
     NSLog(@"Location: %@", NSStringFromCGPoint(location));

}

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{

     CGRect bounds = [self bounds]; 

     UITouch* touch = [[event touchesForView:self] anyObject]; 
     location = [touch locationInView:self];
     NSLog(@"Location: %@", NSStringFromCGPoint(location));

}

Answer 1

由于我无法发表评论，我必须发表回答。您是否尝试将视图的背景颜色设置为不同的颜色，以便您可以确定它是否位于左上角？

Answer 2

以下是我对该观点的看法：

@implementation TouchesView

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        [self setUserInteractionEnabled:YES];
        [self setBackgroundColor:[UIColor colorWithRed:1.0f green:0.6f blue:0.6f alpha:1.0f]];
    }
    return self;
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    CGPoint touch = [[touches anyObject] locationInView:self];
    NSLog(@"(%.1f, %.1f)", touch.x, touch.y);
    NSLog(@"%@", NSStringFromCGPoint(touch));
}

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

- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{}

- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event{}

@end

这是初始化并将其添加到视图控制器：

TouchesView *touchView = [[TouchesView alloc] initWithFrame:self.view.bounds];
[self.view addSubview:touchView];

这对我来说很好。

Answer 3

通过将“状态栏最初隐藏”设置为YES，可以修复y值的-20偏移。问题的其余部分看起来像是硬件问题，因为每次在iPad上运行程序时，我都会得到不同的x和y值范围。在模拟器上运行程序时我没有遇到这个问题。在模拟器上，x值的范围是1到767，y值的范围是1到1023，这是非常正确的。

触摸位置的值超出了视图的范围

3 个答案: