ios - 仅当您的手指在 UIImage 上时才拖动 UIImage

Question

我成功地编写了一个可拖动的图像，但是，如果你随机点击屏幕上的某个地方，它只会将自己传送到那个点。我不想要那个！当您的手指在图像上时，如何使图像仅可拖动？这是我的代码：

-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    UITouch *touch = [[event allTouches] anyObject];
    CGPoint location = [touch locationInView:touch.view];
    symbol1.center = location;
}
-(void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
    [self touchesBegan:touches withEvent:event];
}