Java-Android,将ListView绑定到SQLite数据库

我有一个SQLiteDatabase帮助器,它仅从数据库返回一个带有名称列的游标：

public Cursor getNames() {
    Cursor cursor = db.query(TABLE_NAME, new String[] {NAME}, null, null, null, null, null);
    return cursor;
}

我试图将此光标绑定到布局中包含的一个简单的ListView：

<ListView
    android:id="@android:id/list"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >
</ListView>

Java：

 Cursor cursor = db.getNames();
    startManagingCursor(cursor);

    ListAdapter adapter = new SimpleCursorAdapter (
            this,
            android.R.layout.simple_list_item_1,
            cursor,
            new String[] {constants.NAME},
            new int[] {android.R.id.text1}
            );

    setListAdapter(adapter);

我已按照我可以找到的所有教程进行操作,但该应用程序仍然意外停止.请告诉我我做错了！

这是LOGCAT跟踪,希望这就是您需要的：

12-03 17:18:41.557: E/AndroidRuntime(30413): FATAL EXCEPTION: main
12-03 17:18:41.557: E/AndroidRuntime(30413): java.lang.RuntimeException: Unable to start activity ComponentInfo{george.frost.YourCarbDatabase/com.android.CarbCount.Search}: java.lang.IllegalArgumentException: column '_id' does not exist
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1659)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1675)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.app.ActivityThread.access$1500(ActivityThread.java:121)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:943)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.os.Handler.dispatchMessage(Handler.java:99)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.os.Looper.loop(Looper.java:130)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.app.ActivityThread.main(ActivityThread.java:3701)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at java.lang.reflect.Method.invokeNative(Native Method)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at java.lang.reflect.Method.invoke(Method.java:507)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:624)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at dalvik.system.NativeStart.main(Native Method)
12-03 17:18:41.557: E/AndroidRuntime(30413): Caused by: java.lang.IllegalArgumentException: column '_id' does not exist
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.database.AbstractCursor.getColumnIndexOrThrow(AbstractCursor.java:314)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.widget.CursorAdapter.init(CursorAdapter.java:111)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.widget.CursorAdapter.<init>(CursorAdapter.java:90)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.widget.ResourceCursorAdapter.<init>(ResourceCursorAdapter.java:47)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.widget.SimpleCursorAdapter.<init>(SimpleCursorAdapter.java:84)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at com.android.CarbCount.Search.onCreate(Search.java:42)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
12-03 17:18:41.557: E/AndroidRuntime(30413):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1623)
12-03 17:18:41.557: E/AndroidRuntime(30413):    ... 11 more

解决方法:

不推荐使用startManagingCursor()方法.您应该改用Loader API.如果您要定位的API级别低于11的设备,则需要使用compatibility library.

由于它表明您只是想从SQLiteDatabase加载某些数据,因此您无需创建ContentProvider,但可以扩展Loader.可以在此处找到示例和更多信息：CursorLoader usage without ContentProvider

另外,如果“活动”仅显示ListView,则可能要切换到ListActivity,因为它使绑定数据和获取ID(例如)更加容易.

自您发布LogCat以来：

问题在于,SimpleCursorAdapter类需要一个名为_id的列来获取数据库中每一行数据的ID.有关该问题的更多信息,请参见：Android column ‘_id’ does not exist?

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