使用 SQLite 填充 ListView 的问题

Question

我正在尝试将我自己的 SQLite db 填充到 android listview 中以供查看，但有一个问题，代码运行但会生成“意外退出”。

我检查了我的 DDMS，模拟器在数据库中有我的 SQLite 文件，该文件是从资产文件中复制的。

我不确定这里出了什么问题，谁能给我一些建议，我应该从哪里开始？或者我在下面提供的代码有什么问题吗？我可以在哪里检查代码中的潜在问题？

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);

}

处理光标的 DrugsDbAdapter.java 在这里

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

Answer 1

我怀疑问题在于您没有向光标提供名为“_id”的列。查看我对Android: column '_id' does not exist problem的回复