Android StrictMode 策略

Question

Android 应用程序遇到了一些 ANR 问题，因此我实现了 StrictMode 策略。以前从未使用过这个，所以希望有人可以帮助解释以下内容:

为什么日志显示 2 个看似相似的违规行为，除了前 4 行和持续时间不同？为什么还是有 2 次违规——这是否意味着代码被执行了两次？

感谢任何帮助

08-15 14:24:14.314: DEBUG/StrictMode(767): StrictMode policy violation; ~duration=13876 ms: android.os.StrictMode$StrictModeDiskWriteViolation: policy=17 violation=1
    at android.os.StrictMode$AndroidBlockGuardPolicy.onWriteToDisk(StrictMode.java:732)
    at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1791)
    at com.j256.ormlite.android.AndroidCompiledStatement.execSql(AndroidCompiledStatement.java:151)
    at com.j256.ormlite.android.AndroidCompiledStatement.runUpdate(AndroidCompiledStatement.java:70)
    at com.j256.ormlite.stmt.StatementExecutor.update(StatementExecutor.java:382)
    at com.j256.ormlite.dao.BaseDaoImpl.update(BaseDaoImpl.java:374)
    at conx.Repositories.JobRepository.update(JobRepository.java:381)
    at conx.Presenters.JobSchedulePresenter.onSave(JobSchedulePresenter.java:200)
    at conx.Activities.JobScheduleActivity.onSaveEvent(JobScheduleActivity.java:111)
    at conx.Activities.JobScheduleActivity.access$100(JobScheduleActivity.java:43)
    at conx.Activities.JobScheduleActivity$2.onChildClick(JobScheduleActivity.java:169)
    at android.widget.ExpandableListView.handleItemClick(ExpandableListView.java:588)
    at android.widget.ExpandableListView.performItemClick(ExpandableListView.java:527)
    at android.widget.AbsListView$PerformClick.run(AbsListView.java:1877)
    at android.os.Handler.handleCallback(Handler.java:587)
    at android.os.Handler.dispatchMessage(Handler.java:92)
    at android.os.Looper.loop(Looper.java:130)
    at android.app.ActivityThread.main(ActivityThread.java:3835)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:507)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:864)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:622)
    at dalvik.system.NativeStart.main(Native Method)

 08-15 14:24:14.314: DEBUG/StrictMode(767): StrictMode policy violation; ~duration=12086 ms: android.os.StrictMode$StrictModeDiskWriteViolation: policy=17 violation=1
    at android.os.StrictMode$AndroidBlockGuardPolicy.onWriteToDisk(StrictMode.java:732)
    at android.database.sqlite.SQLiteStatement.execute(SQLiteStatement.java:52)
    at android.database.sqlite.SQLiteDatabase.execSQL(SQLiteDatabase.java:1809)
    at com.j256.ormlite.android.AndroidCompiledStatement.execSql(AndroidCompiledStatement.java:151)
    at com.j256.ormlite.android.AndroidCompiledStatement.runUpdate(AndroidCompiledStatement.java:70)
    at com.j256.ormlite.stmt.StatementExecutor.update(StatementExecutor.java:382)
    at com.j256.ormlite.dao.BaseDaoImpl.update(BaseDaoImpl.java:374)
    at conx.Repositories.JobRepository.update(JobRepository.java:381)
    at conx.Presenters.JobSchedulePresenter.onSave(JobSchedulePresenter.java:200)
    at conx.Activities.JobScheduleActivity.onSaveEvent(JobScheduleActivity.java:111)
    at conx.Activities.JobScheduleActivity.access$100(JobScheduleActivity.java:43)
    at conx.Activities.JobScheduleActivity$2.onChildClick(JobScheduleActivity.java:169)
    at android.widget.ExpandableListView.handleItemClick(ExpandableListView.java:588)
    at android.widget.ExpandableListView.performItemClick(ExpandableListView.java:527)
    at android.widget.AbsListView$PerformClick.run(AbsListView.java:1877)
    at android.os.Handler.handleCallback(Handler.java:587)
    at android.os.Handler.dispatchMessage(Handler.java:92)
    at android.os.Looper.loop(Looper.java:130)
    at android.app.ActivityThread.main(ActivityThread.java:3835)
    at java.lang.reflect.Method.invokeNative(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:507)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:864)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:622)
    at dalvik.system.NativeStart.main(Native Method)

Answer 1

StrictMode 违规表明您正在导致 ANR 问题的 UI 线程上执行 SQLite 查询。

尝试在单独的线程上执行数据库交互，这将防止出现 ANR 问题并防止显示这些 StrictMode 违规行为。

通过浏览 LogCat 输出，它看起来像是发生在 conx.Activities.JobScheduleActivity.onSaveEvent

中

一些有用的读物​​:

• http://developer.android.com/guide/components/processes-and-threads.html
• http://www.vogella.com/articles/AndroidPerformance/article.html