我正在处理数据库,我试图用我的表的每一行填充一个ListView。我已经成功创建并查询了数据,但我无法使用SimpleCursorAdapter获得任何显示在ListView中的内容。SimpleCursorAdapter来填充ListView
public class History extends ListActivity {
SQLiteDatabase db;
DbHelper DbHelper;
ListView lv;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.history);
DbHelper = new DbHelper(this);
db = DbHelper.getWritableDatabase();
lv = getListView();
final String[] from = { DbHelper.TYPE, DbHelper.TITLE, DbHelper.CONTENT };
final String[] column = { DbHelper.C_ID, DbHelper.TYPE, DbHelper.TITLE,
DbHelper.CONTENT };
final int[] to = { R.id.list_row_title, R.id.list_row_content };
Cursor cursor = db.query(DbHelper.TABLE_NAME, column, null, null, null,
null, null);
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this,
R.layout.history_list_row, cursor, from, to);
lv.setAdapter(adapter);
/*
* Display as Toast for development purposes
*/
// move to first row
cursor.moveToFirst();
// move to the next item each time
while (cursor.moveToNext()) {
// get string and column index from cursor
String name = cursor
.getString(cursor.getColumnIndex(DbHelper.TYPE));
String title = cursor.getString(cursor
.getColumnIndex(DbHelper.TITLE));
String content = cursor.getString(cursor
.getColumnIndex(DbHelper.CONTENT));
Toast.makeText(this,
"Title: " + title + "\n" + "Content: " + content,
Toast.LENGTH_SHORT).show();
}
cursor.close();
}
}
这是我的自定义的ListView行从数据库
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<TextView
android:id="@+id/list_row_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Title"
android:textAppearance="?android:attr/textAppearanceLarge" />
<TextView
android:id="@+id/list_row_content"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Content"
android:textAppearance="?android:attr/textAppearanceMedium" />
<TextView
android:id="@+id/list_row_type"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Type"
android:textAppearance="?android:attr/textAppearanceSmall" />
敬酒消息显示完美显示3个字符串,但没有出现在ListView。
我不认为你应该搞砸,更不要关闭适配器外的光标,因为它会弄乱光标位置和加载数据。关闭的光标在你的适配器内不好。 – ebarrenechea 2013-02-22 00:45:50
如果你不'',你可以将'null'传递给['changeCursor(Cursor)'](http://developer.android.com/reference/android/widget/CursorAdapter.html#changeCursor(android.database.Cursor)不再需要它了。如果你使用['LoaderCallbacks'](http://developer.android.com/reference/android/app/LoaderManager.LoaderCallbacks.html),你可以在['onLoaderReset()'](http:// developer .android.com/reference/android/app/LoaderManager.LoaderCallbacks.html#onLoaderReset(android.content.Loader))。否则,请勿关闭适配器外部的光标。适配器管理光标本身。 –
2013-02-22 01:05:00