用SQLite填充ListView的问题

如何解决用SQLite填充ListView的问题

| 我正在尝试将自己的sqlite数据库填充到android listview中进行查看，但是有问题，代码可以运行，但是会生成“意外退出”。我已经检查了DDMS，并且模拟器在数据库中有我的sqlite文件，该文件是从资产文件复制的。我不确定这里出了什么问题，谁能给我一些应该从哪里开始的指导？还是我在下面提供的代码有什么问题？我在哪里可以检查代码中的潜在纠结？谢谢！！！

private void fillData() {

    Cursor drugsCursor = mDbHelper.fetchAllDrugs();
    startManagingCursor(drugsCursor);

        //Creating an array to specify the fields we want
    String[] from = new String[] {DrugsDbAdapter.KEY_ROWID};

        //and an array of the fields we want to bind in the view
    int[] to = new int[] {R.id.text1};

        //To Create the simple cursor adapter and set it to display
    SimpleCursorAdapter drugs = new SimpleCursorAdapter(this,R.layout.drug_row,drugsCursor,from,to);

    setlistadapter(drugs);

}

这里是处理Cursor的DrugsDbAdapter.java

public Cursor fetchAllDrugs() {     
    return mDb.query(DATABASE_TABLE,new String[] {KEY_ROWID,KEY_DRUG,KEY_CONTENT,KEY_INDICATION,KEY_DOSAGE,KEY_SPECIALPRECAUTION},null,null);    
}

我的LogCat的输出（输出的红色部分-我应该发布整个日志吗？）是：

05-25 18:12:22.338: WARN/dalvikvm(27763): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763): FATAL EXCEPTION: main
05-25 18:12:22.434: ERROR/AndroidRuntime(27763): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.paad.medBoxsd/com.paad.medBoxsd.medBoxsd}: java.lang.NullPointerException
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at android.app.ActivityThread.performlaunchActivity(ActivityThread.java:2663)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at android.app.ActivityThread.access$2300(ActivityThread.java:125)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at android.os.Handler.dispatchMessage(Handler.java:99)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at android.os.Looper.loop(Looper.java:123)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at android.app.ActivityThread.main(ActivityThread.java:4627)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at java.lang.reflect.Method.invokeNative(Native Method)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at java.lang.reflect.Method.invoke(Method.java:521)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at dalvik.system.NativeStart.main(Native Method)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763): Caused by: java.lang.NullPointerException
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at com.paad.medBoxsd.medBoxsd.fillData(medBoxsd.java:67)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at com.paad.medBoxsd.medBoxsd.onCreate(medBoxsd.java:56)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     at android.app.ActivityThread.performlaunchActivity(ActivityThread.java:2627)
05-25 18:12:22.434: ERROR/AndroidRuntime(27763):     ... 11 more
05-25 18:12:22.514: WARN/ActivityManager(59):   Force finishing activity com.paad.medBoxsd/.medBoxsd
05-25 18:12:23.034: WARN/ActivityManager(59): Activity pause timeout for HistoryRecord{450fc298 com.paad.medBoxsd/.medBoxsd}

解决方法

我怀疑问题是您没有向游标提供名为“ _id”的列。查看我对Android的回答：列“ _id”不存在问题