iosobjective-cc4

image as button C4

I'm trying to add an action once an image was tapped. I first tried adding a C4Button and then giving it an image but that didn't work out at all. So now I'm trying to just add a tap function to an image here is the code

-(void)setup{
//IMAGE AS BUTTON
    C4Image *photoButtonImage=[C4Image imageNamed:@"icons-02.png"];
    photoButtonImage.height=NavBarHeight;
    photoButtonImage.center=CGPointMake(self.canvas.width/2, self.canvas.height-NavBarHeight/2);
    [self.canvas addImage:photoButtonImage];
    [photoButtonImage addGesture:TAP name:@"tap" action:@"tapped"];
}
-(void)tapped {
    C4Log(@"tapped!");
}

applying the [photoButtonImage addGesture:TAP name:@"tap" action:@"tapped"]; method to self totally works fine but nothing happens if I add it to the image (PhotoButtonImage). I've looked into 2 answers (Gesture controls crash when calling methods on C4WorkSpace.m and How do I apply a UILongPressGestureRecognizer to a shape in C4?). They are for shapes and I thought it should just work the same for images, but apparently it doesn't...

Solution

  • Adam's answer is correct for gestures. Generally, you want to use them when you want some extra / custom functionality for objects.

    However, in your case you want to simply use the image as a button, you can do the following to achieve that without having to use a gesture:

    [self listenFor:@"touchesBegan" fromObject:photoImage andRunMethod:@"aMethod"];

    The reason for this is that all C4 objects will post basic touch notifications by default.