Detect Any touch Event across Application in iphone

Question

My objective is to detect any touch event inside My Application on any view... (i.e Inside my application any touch event in anywhere should be detected...) I have tried it by subclassing my appDelegate Class with UIApplication but it is giving me error

how to detect idle user in iphone-sdk

how to resolve that error Or implement it in any other way...

Please Help

Thanks

score 1 · Accepted Answer · answered Jun 24 '10 at 10:32

1

OK, I've answered that linked question. However you may want to consider a different approach, which is using class_replaceMethod() to "swizzle" the UIView touch methods with your own implementation.

answered Jun 24 '10 at 10:32

but doesn't i need to do this for each view...? – Mihir Mehta Jun 24 '10 at 11:36
@mihirpmehta no, do it once for the UIView class. – Jun 24 '10 at 13:08
Hi Graham... Thanks but i have TabBar controller in main window and 5 viewController for 5 tabs... I am not sure where to use class_replaceMethod() out of them... – Mihir Mehta Jun 25 '10 at 04:22

gjpc · Answer 2 · 2012-06-25T20:22:48.467

Here is a detector that tested ok on IOS 4 and 5. There is a caveat. If you are using gesture recognizers, you must set the global AppTouched to false when they get to state UIGestureRecognizerStateEnded.

#import <objc/runtime.h> 

Boolean AppTouched = false;     // provide a global for touch detection    

static IMP iosBeginTouch = nil; // avoid lookup every time through
static IMP iosEndedTouch = nil;
static IMP iosCanedTouch = nil;

// implement detectors for UIView
@implementation  UIView (touchesBeganDetector)
- (void)touchesBeganDetector:(NSSet *)touches withEvent:(UIEvent *)event
{
    AppTouched = true;

    if ( iosBeginTouch == nil )
        iosBeginTouch = [self methodForSelector:
                              @selector(touchesBeganDetector:withEvent:)];

    iosBeginTouch( self, @selector(touchesBegan:withEvent:), touches, event );
}
@end

@implementation  UIView (touchesEndedDetector)
- (void)touchesEndedDetector:(NSSet *)touches withEvent:(UIEvent *)event
{
    AppTouched = false;

    if ( iosEndedTouch == nil )
        iosEndedTouch = [self methodForSelector: 
                              @selector(touchesEndedDetector:withEvent:)];

    iosEndedTouch( self, @selector(touchesEnded:withEvent:), touches, event );
}
@end

@implementation  UIView (touchesCancledDetector)
- (void)touchesCancledDetector:(NSSet *)touches withEvent:(UIEvent *)event
{
    AppTouched = false;

    if ( iosCanedTouch == nil )
        iosCanedTouch = [self methodForSelector:     
                              @selector(touchesCancledDetector:withEvent:)];

    iosCanedTouch( self, @selector(touchesCancelled:withEvent:), touches, event );
}
@end

// http://stackoverflow.com/questions/1637604/method-swizzle-on-iphone-device
static void Swizzle(Class c, SEL orig, SEL repl )
{
    Method origMethod = class_getInstanceMethod(c, orig );
    Method newMethod  = class_getInstanceMethod(c, repl );

    if(class_addMethod( c, orig, method_getImplementation(newMethod),
                                 method_getTypeEncoding(newMethod)) )

        class_replaceMethod( c, repl, method_getImplementation(origMethod), 
                                      method_getTypeEncoding(origMethod) );
    else
        method_exchangeImplementations( origMethod, newMethod );
}

@interface  touchDetector : NSObject {}
- (id) init;
@end

@implementation touchDetector

- (id) init
{
     if ( ! [ super init ] )
         return nil;

    SEL rep = @selector( touchesBeganDetector:withEvent: );
    SEL orig = @selector( touchesBegan:withEvent: );
    Swizzle( [UIView class], orig, rep );

    rep = @selector( touchesEndedDetector:withEvent: );
    orig = @selector( touchesEnded:withEvent: );
    Swizzle( [UIView class], orig, rep );

    rep = @selector( touchesCancledDetector:withEvent: );
    orig = @selector( touchesCancelled:withEvent: );
    Swizzle( [UIView class], orig, rep );

    return self;
}
@end

I am using iOS 7.1 and after using this in a slightly different implementation, I can't get the source UIView to receive touchesBegan, etc to respond. I get EXC_BAD_ACCESS code=2 address=0x0 on the line iosBeginTouch( self, @selector(touchesBegan:withEvent:), touches, event ); — George L, May 19 '14 at 00:33

Detect Any touch Event across Application in iphone

2 Answers2