触摸移动有问题

Question

我想确保移动的按钮按住图片(如在某些策略)。但是当我移动图像时，它会抖动。下面是代码:

// PROPERTY
@property (nonatomic, retain) UIView *gameView;
@property GameState gameState; // for current state == Game
@property CGPoint touchPoint;
@property CGPoint screenOffset;
// INICIALIZE
_gameView = [[UIView alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
UIGraphicsBeginImageContext(_gameView.frame.size);
[[UIImage imageNamed:iname] drawInRect:_gameView.bounds];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
_gameView.backgroundColor = [UIColor colorWithPatternImage:image];
_gameView.userInteractionEnabled = YES;
[self.view addSubview:_gameView];
// METHODS
- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [[event allTouches] anyObject];
    switch (_gameState) {
        case Start:
            break;
        case Game:
            if ([touch view] == _gameView) {
                _touchPoint = [touch locationInView:touch.view];
                NSLog(@"startTouch");
            }
            break;
        default:
            break;
    }
}
- (void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint currentTouchPoint = [touch locationInView:touch.view];
    switch (_gameState) {
        case Start:
            break;
        case Game:
            if ([touch view] == _gameView) {
                NSLog(@"%f%f", [touch locationInView:touch.view].x, [touch locationInView:touch.view].y);
                currentTouchPoint.x += _screenOffset.x - _touchPoint.x;
                currentTouchPoint.y += _screenOffset.y - _touchPoint.y;
                _gameView.center = currentTouchPoint;
            }
            break;
        default:
            break;
    }
}
- (void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint endedTouchPoint = [touch locationInView:touch.view];
    switch (_gameState) {
        case Start:
            break;
        case Game:
            if ([touch view] == _gameView) {
                _screenOffset.x += endedTouchPoint.x - _touchPoint.x;
                _screenOffset.y += endedTouchPoint.y - _touchPoint.y;
                _gameView.center = _screenOffset;
                NSLog(@"endTouch");
            }
            break;
        default:
            break;
    }
}

即使稍微移动一下鼠标，图像也会跳跃。以下是日志中显示的内容:

startTouch
206.000000    319.000000
206.000000    338.000000
209.000000    342.000000
211.000000    367.000000
217.000000    393.000000
228.000000    435.000000
291.000000    580.000000
244.000000    470.000000
316.000000    620.000000
250.000000    470.000000
330.000000    620.000000
263.000000    468.000000
...
endTouch

同时我将指针向一个方向移动。错误在哪里?

我不想移动所有的对象。我找到了理由。如果写:

_gameView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"field1.png"]];
_gameView.frame = [[UIScreen mainScreen] bounds]; 
//_gameView.userInteractionEnabled = YES; 

这是工作，但如果取消注释最后一个字符串问题返回。但是我的程序需要=(

Answer 1

你可以用AddView的父视图的坐标来确定触摸的位置:

CGPoint location = [touch locationInView:AddView.superview];