我试图通过从数据库中获取所有子任务来显示列表视图。我得到一个非法的争论例外。但我很惊讶，因为我正在查询另一个表，并且异常显示一些其他表列不存在。请允许任何人告诉我代码中发生了什么以及缺少什么：
我的列表查看代码：
public void populateListView() {
SQLiteDataBaseAdapter adapter = new SQLiteDataBaseAdapter(this);
Cursor cursor = adapter.getAllSubTaskData();
// Log.d("Pana", "The value of cursor is " +Integer.parseInt(String.valueOf(cursor.toString())));
String[] fromFieldNames = new String[]{SQLiteHelper.UIDCHILD, SQLiteHelper.SUB_TASK_NAME};
int[] toViewIds = new int[]{R.id.textViewNumber, R.id.textViewName};
SimpleCursorAdapter myCursorAdapter;
myCursorAdapter = new SimpleCursorAdapter(this, R.layout.custom_list_row, cursor, fromFieldNames, toViewIds, 0);
final ListView listView = (ListView) findViewById(R.id.listViewSubTask);
listView.setAdapter(myCursorAdapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(getApplicationContext(), "The position of the item clicked is " + position, Toast.LENGTH_LONG).show();
Intent intent = new Intent();
intent.setClass(getApplicationContext(), SubTaskDetail.class);
intent.putExtra("position", Integer.toString(position + 1)); //position starts from 0, but in db row starts from 1
startActivity(intent);
}
});
}
我的数据库代码：
public Cursor getAllSubTaskData() {
db = helper.getWritableDatabase();
String[] columns = {SQLiteHelper.UIDCHILD,
SQLiteHelper.SUB_TASK_NAME,
SQLiteHelper.CONTACT_NAME,
SQLiteHelper.CONTACT_NUMBER,
//SQLiteHelper.CONTACT_EMAIL,
SQLiteHelper.DESCRIPTION,
SQLiteHelper.REMARKS,
SQLiteHelper.DATE,
SQLiteHelper.TIME,
SQLiteHelper.ESTIMATED_COMPLETION_DATE,
SQLiteHelper.ESTIMATED_COMPLETION_TIME,
SQLiteHelper.ACTUAL_COMPLETION_DATE,
SQLiteHelper.ACTUAL_COMPLETION_TIME,
SQLiteHelper.NOTIFY_DATE,
SQLiteHelper.NOTIFY_TIME};
Cursor cursor = db.query(SQLiteHelper.TABLE_NAME_CHILD, columns, null, null, null, null, null);
}
if (cursor != null) {
cursor.moveToFirst();
}
return cursor;
}
我的ADB追踪：
03-12 18:57:39.189 1502-1502/com.ms.t.tms E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.ms.t.tms, PID: 1502
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.ms.t.tms/com.ms.t.tms.SubTaskList}: java.lang.IllegalArgumentException: column '_id' does not exist
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
at android.app.ActivityThread.access$800(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
Caused by: java.lang.IllegalArgumentException: column '_id' does not exist
at android.database.AbstractCursor.getColumnIndexOrThrow(AbstractCursor.java:303)
at android.widget.CursorAdapter.init(CursorAdapter.java:172)
at android.widget.CursorAdapter.<init>(CursorAdapter.java:149)
at android.widget.ResourceCursorAdapter.<init>(ResourceCursorAdapter.java:91)
at android.widget.SimpleCursorAdapter.<init>(SimpleCursorAdapter.java:104)
at com.ms.t.tms.SubTaskList.populateListView(SubTaskList.java:57)
at com.ms.t.tms.SubTaskList.onCreate(SubTaskList.java:33)
at android.app.Activity.performCreate(Activity.java:5933)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
at android.app.ActivityThread.access$800(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
该表的数据库架构：
public static final String CREATE_TABLE_CHILD = " CREATE TABLE " + TABLE_NAME_CHILD +
"(" + UIDCHILD + " INTEGER PRIMARY KEY AUTOINCREMENT, " + SUB_TASK_NAME + " VARCHAR(250)," + CONTACT_NAME + " VARCHAR(250)," + CONTACT_NUMBER + " VARCHAR(250),"
+ CONTACT_EMAIL + " VARCHAR(250)," + DESCRIPTION + " VARCHAR(250), " + REMARKS + " VARCHAR(250),"
+ DATE + " VARCHAR(250)," + TIME + " VARCHAR(250)," + ESTIMATED_COMPLETION_DATE + " VARCHAR(250), " + ESTIMATED_COMPLETION_TIME + " VARCHAR(250), "
+ ACTUAL_COMPLETION_DATE + " VARCHAR(250), " + ACTUAL_COMPLETION_TIME + " VARCHAR(250), " + NOTIFY_DATE + " VARCHAR(250), " + NOTIFY_TIME + " VARCHAR(250), " + SUB_TASK_NUMBER + " VARCHAR(250), "
+ " FOREIGN KEY (" + UIDCHILD + ") REFERENCES " + TABLE_NAME + " (" + TASK_NAME + "));";
请告诉我遗漏的内容并帮助我克服这个问题。提前谢谢。
答案 0 :(得分：1)
您必须检查SQLiteHelper.UIDCHILD的字段。如果该字段命名为id，请将其更改为_id。或者在您查询时：而不是id使用id AS _id。 Listview要求将行ID命名为_id
答案 1 :(得分：1)
要使用需要名为_id的列的游标，请编辑表创建语句并添加名为_id的列（或将UIDCHILD值更改为“_id”）。