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POUIImage detecting touch and dragging
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copied!<p>Fairly common question this, to which I have a few answers and I'm nearly there. I have a button which when pressed, will create an image (code as follows)</p> <p>(numImages is set on load to ZERO and is used as a count up for the tag numbers of all images created)</p> <pre><code>UIImage *tmpImage = [[UIImage imageNamed:[NSString stringWithFormat:@"%i.png", sender.tag]] retain]; UIImageView *myImage = [[UIImageView alloc] initWithImage:tmpImage]; numImages += 1; myImage.userInteractionEnabled = YES; myImage.tag = numImages; myImage.opaque = YES; [self.view addSubview:myImage]; [myImage release]; </code></pre> <p>I then have a touchesBegan method which will detect what's touched. What I need it to do is to allow the user to drag the newly created image. It's nearly working, but the image flickers all over the place when you drag it. I can access the image which you click on as I can get it's TAG, but I just cannot drag it nicely. </p> <pre><code>- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event { UITouch *touch = [[event allTouches] anyObject]; CGPoint location = [touch locationInView:touch.view]; if (touch.view.tag > 0) { touch.view.center = location; } NSLog(@"tag=%@", [NSString stringWithFormat:@"%i", touch.view.tag]); } - (void) touchesMoved:(NSSet *)touches withEvent: (UIEvent *)event { [self touchesBegan:touches withEvent:event]; } </code></pre> <p>It works, in that I get an output of the tag for each image as I click on them. But when I drag, it flashes... any ideas?</p>

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