问题描述

有一个RecycleView视图组件，数据变更得时候进行了增加和删除操作，频繁触发 增加、删除数据得操作，低概率出现此问题，代码片段无法展示，可以语言描述一下代码片段

1. recycleview使用了adapter来展示数据
2. adapter初始化子view需要一个list
3. list可能会调用remove、add操作，频繁调用会触发ConcurrentModificationException异常

下面是错误堆栈信息

	2022-04-25 10:40:27.082 14788-14788/com.xx E/AndroidRuntime: FATAL EXCEPTION: main
	    Process: com.xx, PID: 14788
	    java.util.ConcurrentModificationException
	        at java.util.ArrayList$SubList.size(ArrayList.java:1057)
	        at com.chad.library.adapter.base.BaseQuickAdapter.getItemCount(BaseQuickAdapter.java:698)
	        at android.support.v7.widget.RecyclerView.dispatchLayoutStep1(RecyclerView.java:3722)
	        at android.support.v7.widget.RecyclerView.onMeasure(RecyclerView.java:3219)
	        at android.view.View.measure(View.java:22238)
	        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6682)
	        at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1514)
	        at android.widget.LinearLayout.measureVertical(LinearLayout.java:806)
	        at android.widget.LinearLayout.onMeasure(LinearLayout.java:685)
	        at android.view.View.measure(View.java:22238)
	        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6682)
	        at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1514)
	        at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1167)
	        at android.widget.LinearLayout.onMeasure(LinearLayout.java:687)
	        at android.view.View.measure(View.java:22238)
	        at android.support.constraint.ConstraintLayout.internalMeasureChildren(ConstraintLayout.java:1227)
	        at android.support.constraint.ConstraintLayout.onMeasure(ConstraintLayout.java:1572)
	        at android.view.View.measure(View.java:22238)
	        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6682)
	        at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
	        at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:141)
	        at android.view.View.measure(View.java:22238)
	        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6682)
	        at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1514)
	        at android.widget.LinearLayout.measureVertical(LinearLayout.java:806)
	        at android.widget.LinearLayout.onMeasure(LinearLayout.java:685)
	        at android.view.View.measure(View.java:22238)
	        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6682)
	        at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
	        at android.view.View.measure(View.java:22238)
	        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6682)
	        at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1514)
	        at android.widget.LinearLayout.measureVertical(LinearLayout.java:806)
	        at android.widget.LinearLayout.onMeasure(LinearLayout.java:685)
	        at android.view.View.measure(View.java:22238)
	        at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:6682)
	        at android.widget.FrameLayout.onMeasure(FrameLayout.java:185)
	        at com.android.internal.policy.DecorView.onMeasure(DecorView.java:725)
	        at android.view.View.measure(View.java:22238)
	        at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2523)
	        at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1550)
	        at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1818)
	        at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1438)
	        at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6982)
	        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:916)
	        at android.view.Choreographer.doCallbacks(Choreographer.java:728)
	        at android.view.Choreographer.doFrame(Choreographer.java:660)
	        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:902)
	        at android.os.Handler.handleCallback(Handler.java:790)
	        at android.os.Handler.dispatchMessage(Handler.java:99)
	        at android.os.Looper.loop(Looper.java:164)
	        at android.app.ActivityThread.main(ActivityThread.java:6548)
	        at java.lang.reflect.Method.invoke(Native Method)
	        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
	        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:857)
	

解决方案：

1. 在使用iterator迭代的时候使用synchronized或者Lock进行同步
2. 使用并发容器CopyOnWriteArrayList代替ArrayList和Vector。