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iosuiscrollviewuisegmentedcontroltouches

uiscrollview won't cancel content touches for uisegmentedcontrol


I've subclassed th UIScrollView and overriden the touchesShouldCancelInContentView: method the following way:

-(BOOL)touchesShouldCancelInContentView:(UIView *)view

{
    if ([view isKindOfClass:[UIButton class]] || [view isKindOfClass:[UISegmentedControl class]]) {
        return YES;
    }

    if ([view isKindOfClass:[UIControl class]]) {
        return NO;
    }

    return YES;
}

It works perfectly for UIButton, but it doesn't work for UISegmentedControl. Any help would be appreciated


Solution

  • Finally figured it out. Had to subclass both UISegmentedControl and UIScrollView.

    1.) added a new property for UISegmentedControl:

    @property (nonatomic, assign) BOOL touchProcessed;
    

    2.) overloaded the following methods of the UISegmentedControl:

    -(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
    {
        if (touchProcessed) {
            [super touchesBegan:touches withEvent:event];
        }
        else {
            [self.nextResponder touchesBegan:touches withEvent:event];
        }
        self.touchProcessed = NO;
    }
    
    -(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
    {
        [self.nextResponder touchesMoved:touches withEvent:event];
    }
    
    -(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
    {
        [self.nextResponder touchesEnded:touches withEvent:event];
    }
    

    3.) overloaded the following methods of th UIScrollview:

    -(BOOL)touchesShouldCancelInContentView:(UIView *)view
    { 
        if ([view isKindOfClass:[self class]])
        {
            return YES; //if there are two nested custom scrollviews  
        }
    
        if ([view isKindOfClass:[UIButton class]] || [view isKindOfClass:[CustomSegmentedControl class]] || [[view superview] isKindOfClass:[CustomSegmentedControl class]]) {
            return YES;
        }
    
        if ([view isKindOfClass:[UIControl class]]) {
            return NO;
        }
    
        return YES;
    }
    
    -(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
    {
        if (!self.dragging) {
            for (UIView *sv in self.subviews) {
                if ([sv isKindOfClass:[CustomSegmentedControl class]])
                {   //if there is more than one add a tag or tomething
                    [(CustomSegmentedControl *)sv setTouchProcessed:YES];
                    [sv touchesBegan:touches withEvent:event];
                    return;
                 }
            }
        }
    }
    

    Works perfectly!