我知道这个问题以前曾被问过和回答过,但是我遵循了多个教程都没有用。
我只是认为,如果我编写代码,也许有人可以帮助并指出正确的方向。我不会说谎,我是一个笨拙的菜鸟,但到目前为止我仍然很喜欢它(嗯,无论如何到目前为止)。发生的一切是在我加载 Activity 时,它强制关闭并显示以下错误消息:
06-14 20:04:08.162: ERROR/AndroidRuntime(17605): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.magic8/com.example.magic8.AnswerList}: java.lang.UnsupportedOperationException: addView(View, LayoutParams) is not supported in AdapterView
所以,就在这里。我的数据库查询是:
public Cursor fetchAnswersList() {
return mDb.query(DATABASE_TABLE, new String[] {KEY_ROWID, "answer"},
null, null, null, null, null, null);
}
然后我的列表查看代码:
public class AnswerList extends Activity {
private Context context;
private DatabaseManager mDbHelper;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.answerlist);
Cursor answers = mDbHelper.fetchAnswersList();
startManagingCursor(answers);
ListView answerList=(ListView)findViewById(R.id.answerList);
String[] from = new String[] {"_id", "answer"};
int[] to = new int[] {R.id.answerItem};
SimpleCursorAdapter cursorAdapter = new SimpleCursorAdapter(context, R.layout.list_item, answers, from, to);
answerList.setAdapter(cursorAdapter);
answerList.setOnItemClickListener(
new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// When clicked, show a toast with the TextView text
setToast("Answer: " + ((TextView) view).getText());
}
});
}
最后但并非最不重要的,这是我的XML:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<LinearLayout
android:id="@+id/addAnswerForm"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:orientation="horizontal">
<EditText
android:id="@+id/addAnswer"
android:layout_weight="1"
android:layout_height="wrap_content"
android:layout_width="wrap_content">
<requestFocus></requestFocus>
</EditText>
<Button
android:text="Add"
android:id="@+id/addAnswer_btn"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
</Button>
</LinearLayout>
<LinearLayout
android:id="@+id/answers"
android:layout_height="match_parent"
android:layout_width="match_parent">
<ListView
android:layout_weight="1"
android:layout_height="wrap_content"
android:id="@+id/answerList"
android:layout_width="match_parent">
<TextView
android:id="@+id/answerItem"
android:layout_height="match_parent"
android:layout_width="match_parent">
</TextView>
</ListView>
</LinearLayout>
</LinearLayout>
最佳答案
您遇到的错误很可能是因为您试图将TextView嵌入到ListView中...
<ListView
android:layout_weight="1"
android:layout_height="wrap_content"
android:id="@+id/answerList"
android:layout_width="match_parent">
<TextView
android:id="@+id/answerItem"
android:layout_height="match_parent"
android:layout_width="match_parent">
</TextView>
</ListView>
从ListView删除TextView,然后尝试以下操作...
String[] from = new String[] {"answer"};
int[] to = new int[] {android.R.id.text1};
SimpleCursorAdapter cursorAdapter = new SimpleCursorAdapter(context, android.R.layout.simple_list_item_1, answers, from, to);
这使用了预定义的Android
android.R.layout.simple_list_item_1
和android.R.id.text1