Question

based on how to add on touch and detect UIImageView on view so i could move it around and not adding one on top of it?

i got around of checking CGRectIntersectsRect single uiimageview. how will i need to check multiple uiimageview?

CORRECT

WRONG

-(void)initImagesAndGesture
{
    UIImage *img = [UIImage imageNamed:@"beer.png"];
    imgView1 = [[UIImageView alloc]initWithImage:img];
    [imgView1 setFrame:CGRectMake(0, 0, 75, 115)];
    [imgView1 setUserInteractionEnabled:YES];
    UIPanGestureRecognizer *recognizer1 = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(handlePan1:)];
    [imgView1 addGestureRecognizer:recognizer1];
    [self.view addSubview:imgView1];

    img = [UIImage imageNamed:@"cups.png"];
    imgView2 = [[UIImageView alloc]initWithImage:img];
    [imgView2 setFrame:CGRectMake(200, 240, 64, 75)];
    [imgView2 setUserInteractionEnabled:YES];
    recognizer1 = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(handlePan1:)];
    [imgView2 addGestureRecognizer:recognizer1];
    [self.view addSubview:imgView2];
}

-(void)handlePan1:(UIPanGestureRecognizer *)recognizer
{
    if (!(CGRectIntersectsRect(imgView1.frame, imgView2.frame)))
    {
        CGPoint pre_moveLocation = [recognizer locationInView:recognizer.view];
        NSLog(@"previous location %@",NSStringFromCGPoint(pre_moveLocation));        

        CGPoint translation = [recognizer translationInView:self.view];
        recognizer.view.center = CGPointMake(recognizer.view.center.x + translation.x, 
                                             recognizer.view.center.y + translation.y);

        [recognizer setTranslation:CGPointMake(0, 0) inView:recognizer.view];
    }
    else 
    {
        NSLog(@"intersect!");

        CGPoint pre_moveLocation = [recognizer locationInView:recognizer.view];
        NSLog(@"previous location %@",NSStringFromCGPoint(pre_moveLocation));
        recognizer.view.center = CGPointMake(pre_moveLocation.x, pre_moveLocation.y);

        [recognizer setTranslation:CGPointMake(0, 0) inView:recognizer.view];

        //[imgView2 setFrame:CGRectMake(200, 240, 64, 75)];
        //[imgView1 setFrame:CGRectMake(0, 0, 75, 115)];

    }
}




-(void)addImgView:(UIPanGestureRecognizer *)recognizer
{
    NSLog(@"tappppp");

    UIImage *img = [UIImage imageNamed:@"beer.png"];
   UIImageView *imgView = [[UIImageView alloc]initWithImage:img];

    CGPoint tapLocation = [recognizer locationInView:recognizer.view];

    [imgView setCenter:CGPointMake(tapLocation.x,tapLocation.y)];     
    [imgView setUserInteractionEnabled:YES];
    UIPanGestureRecognizer *recognizer1 = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(handlePan1:)];
    [imgView addGestureRecognizer:recognizer1];
    [self.view addSubview:imgView];

}


- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    [self initImagesAndGesture];

    UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(addImgView:)];
    tapRecognizer.numberOfTapsRequired = 2;
    tapRecognizer.numberOfTouchesRequired = 1;
    [tapRecognizer setDelegate:self];
    self.view.userInteractionEnabled = YES;

    [self.view addGestureRecognizer:tapRecognizer];   
}

Answer 1

Just iterate through all subviews…

// targetView is the one you are checking...
- (BOOL)isViewIntersectingAnyOtherViews:(UIView*)targetView {
    for (UIView *view in self.view.subviews) {
        if (view == targetView) continue; // Don't check against your own view
        if (CGRectIntersectsRect(view, thisView)) {
            return YES;
        }
    }
    return NO;
}