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Improve Touch Events UIImageView

I have 30-40 tabs open, I've found my answer.. but I'm wishing to improve. The code does work, I am just not sure if it is efficient

The following code shows that I have 2 small images (One using UIImageView, another using UIView) in which I have attached to a UIScrollView, which is attached to a UIView which came with the UIViewController, which is attached to the UIWindow. Pretty basic.

I also have a button attached to the UIViewController to make sure zooming and scrolling worked. (By testing the static location of the button and size)

@interface Wire_TestViewController : UIViewController <UIScrollViewDelegate> {
UIScrollView *scrollview;
}
@end

Implementation:

- (void)test:(UIButton *)sender {  }
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView { return scrollview; }
- (void)viewDidLoad {
    [super viewDidLoad];

    scrollview = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];
    scrollview.delegate = self;
    scrollview.contentSize = CGSizeMake( 320*2, 480*2 );
    scrollview.minimumZoomScale = .1;
    scrollview.maximumZoomScale = 10;
    [self.view addSubview:scrollview];

    UIImageView *view = [[UIImageView alloc] initWithFrame:CGRectMake(320, 320, 20, 20)];
    view.image = [UIImage imageNamed:@"Node.png"];
    view.clearsContextBeforeDrawing = NO;
    [scrollview addSubview:view];

    UIButton *button = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    button.frame = CGRectMake(10, 10, 100, 30);
    button.tag = 51;
    [button setTitle:@"new button" forState:(UIControlState)UIControlStateNormal];
    [button addTarget:self action:@selector(test:) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:button];

    UIView *view2 = [[UIView alloc] initWithFrame:CGRectMake(50, 50, 30, 30)];
    view2.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"WireActive.png"]];
    [scrollview addSubview:view2];

    TestSubclass *test = [[TestSubclass alloc] initWithFrame:CGRectMake(100, 100, 50, 50)];
    test.userInteractionEnabled = TRUE;
    test.image = [UIImage imageNamed:@"Node.png"];
    [scrollview addSubview:test];
}

You'll see near the bottom I have a TestSubclass class made. The code for that is as follows:

@interface TestSubclass : UIImageView {  }
@end

@implementation TestSubclass
- (id)init {
    [super init];
    self.userInteractionEnabled = TRUE;
    return self;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    printf("Being touched...\n");
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
    printf("Touches Ended...\n");
}
@end

The part in which I am happy with is that I have a fully functioning Subclass of UIImageView which works as if it was a UIButton. BUT! without the 7 backgroundImageViews (and the overhead from each of those), without the 6 labels (and the overhead from each of those), without the 6 UIImageViews ("..."), and lastly the amount of un-needed things that UIButt开发者_StackOverflowon offers. I only wanted touch capabilities.. efficiently however. (TouchUpInside, Dragging, etc)

But, now during my research (after the extensive testing to accomplish this much), I've come across in documentation and some examples addGestureRecognizer in UIView. It seems sorta-but not entirely efficient for my needs.

I'm looking for advice, I know there are a couple problems in my code (overrided init, but didn't use it in the above code.. didn't release.. probably some subclassing mistakes (new to subClassing (to be honest)). But anything is much appreciated!! And, I hope others are helped as well!


If you want to have full control capabilities, you must subclass UIControl and use your image with in. The image can be an UIImageView subview or can be drawn in the drawRect method of your subclass or set in the CALayer view content. Note that subclassing UIControl is not the easiest thing to do, but it gives you all "control" feature it seems you are requesting from it and I think is the most efficient or appropriate approach.

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