Find UIGestureRecognizer action (selector) name and target

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臣服心动
臣服心动 2020-12-19 13:37

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

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  •  旧时难觅i
    2020-12-19 13:54

    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 , and that this uses private ivars and a class, so it could get you banned from the App Store.

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