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ios - Find UIGestureRecognizer action (selector) name and target

I'm trying to find which action is triggered by a UIGestureRecognizer on which target. Unfortunately there is no property on a UIGestureRecognizer such as gesture.action or gesture.target. The gesture I'm analyzing is part of UIKit private implementation.

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Here's a code snippet that will list all target/action pairs associated with a gesture recognizer:

Ivar targetsIvar = class_getInstanceVariable([UIGestureRecognizer class], "_targets");
id targetActionPairs = object_getIvar(gesture, targetsIvar);

Class targetActionPairClass = NSClassFromString(@"UIGestureRecognizerTarget");
Ivar targetIvar = class_getInstanceVariable(targetActionPairClass, "_target");
Ivar actionIvar = class_getInstanceVariable(targetActionPairClass, "_action");

for (id targetActionPair in targetActionPairs)
{
    id target = object_getIvar(targetActionPair, targetIvar);
    SEL action = (__bridge void *)object_getIvar(targetActionPair, actionIvar);

    NSLog(@"target=%@; action=%@", target, NSStringFromSelector(action));
}

Note that you'll have to import <objc/runtime.h>, and that this uses private ivars and a class, so it could get you banned from the App Store.


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