查找 UIGestureRecognizer 操作(选择器)名称和目标-移动开发问题

Find UIGestureRecognizer action (selector) name and target(查找 UIGestureRecognizer 操作(选择器)名称和目标)

本文介绍了查找 UIGestureRecognizer 操作(选择器)名称和目标的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我试图找出哪个动作是由哪个目标上的 UIGestureRecognizer 触发的.不幸的是，UIGestureRecognizer 上没有属性，例如 gesture.action 或 gesture.target.我正在分析的手势是 UIKit 私有实现的一部分.

这里是部分答案

stackOverFlow 问题 20066315

解决方案

下面的代码片段将列出与手势识别器关联的所有目标/动作对:

Ivar targetsIvar = class_getInstanceVariable([UIGestureRecognizer class], "_targets");id targetActionPairs = object_getIvar(手势，targetsIvar)；类 targetActionPairClass = NSClassFromString(@"UIGestureRecognizerTarget");Ivar targetIvar = class_getInstanceVariable(targetActionPairClass, "_target");Ivar actionIvar = class_getInstanceVariable(targetActionPairClass, "_action");for (id targetActionPair in targetActionPairs){id 目标 = object_getIvar(targetActionPair, targetIvar);SEL 动作 = (__bridge void *)object_getIvar(targetActionPair, actionIvar);NSLog(@"target=%@; action=%@", target, NSStringFromSelector(action));}

请注意，您必须导入 <objc/runtime.h>，并且这会使用私有 ivars 和类，因此可能会导致您被 App Store 禁止.p>

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.

Partial Answer here

stackOverFlow Question 20066315

解决方案

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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