Question

我正在努力解决这个问题。任何人都可以帮我解决这个问题。请在查询语句的where子句中告诉我出错的地方。我想从所有列中读取值，然后将它们显示出来。

这是我的查询代码：

public Task getTask1(String id) {


        db = helper.getReadableDatabase();

        String selection = SQLiteHelper.UID;

        String[] columns = { SQLiteHelper.UID,
                SQLiteHelper.TASK_NAME, SQLiteHelper.CONTACTS, SQLiteHelper.DESCRIPTION, SQLiteHelper.REMARKS, SQLiteHelper.DATETIME, SQLiteHelper.ESTIMATED_COMPLETION_TIME,
                SQLiteHelper.ACTUAL_COMPLETION_TIME, SQLiteHelper.NOTIFY_TIME};

        String[] selectionArgs = new String[]{String.valueOf(id)};
Cursor cursor = db.query(
        SQLiteHelper.TABLE_NAME,
        columns,                
        selection,              
        selectionArgs,          
        null,                   
        null,                   
        null                    
);

if (cursor != null) {

            cursor.moveToNext();


            task = new Task(
                    cursor.getString(1), cursor.getString(2), cursor.getString(3), cursor.getString(4), cursor.getString(5),
                    cursor.getString(6), cursor. getString(7), cursor.getString(8));

            Log.d("Pana", "The value of Task is" + task);

        }


        return task;
    }

根据建议更新了方法：

public Task getTask1(String id) {


        db = helper.getReadableDatabase();

        String selection = SQLiteHelper.UID;

        String[] columns = { SQLiteHelper.UID,
                SQLiteHelper.TASK_NAME, SQLiteHelper.CONTACTS, SQLiteHelper.DESCRIPTION, SQLiteHelper.REMARKS, SQLiteHelper.DATETIME, SQLiteHelper.ESTIMATED_COMPLETION_TIME,
                SQLiteHelper.ACTUAL_COMPLETION_TIME, SQLiteHelper.NOTIFY_TIME};


        String[] selectionArgs = new String[]{SQLiteHelper.TABLE_NAME, String.valueOf(id)};

        Cursor cursor = db.rawQuery("select * from " + SQLiteHelper.TABLE_NAME + " where _id = ?", selectionArgs);

//        if (cursor != null && cursor.moveToFirst()) {
//
//            task = new Task(
//                    cursor.getString(1), cursor.getString(2), cursor.getString(3), cursor.getString(4), cursor.getString(5),
//                    cursor.getString(6), cursor. getString(7), cursor.getString(8));
//
//            Log.d("Pana", "The value of Task is" + task);
//
//            cursor.close();
//Don't forget to close your cursor, otherwise you will have a memory leak!

        if (cursor != null) {

            while (cursor.moveToNext()) {
                task = new Task(
                        cursor.getString(1), cursor.getString(2), cursor.getString(3), cursor.getString(4), cursor.getString(5),
                        cursor.getString(6), cursor. getString(7), cursor.getString(8));

                Log.d("Pana", "The value of Task is" + task);
            }

            cursor.close();
        }


        return task;


        }

这是我的logcat：

 11:23:06.955    1142-1142/com.ms.t.tms D/AndroidRuntime﹕ Shutting down VM
    --------- beginning of crash
02-27 11:23:06.970    1142-1142/com.ms.t.tms E/AndroidRuntime﹕ FATAL EXCEPTION: main
    Process: com.ms.t.tms, PID: 1142
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.ms.t.tms/com.ms.t.tms.EditScreen}: java.lang.IllegalArgumentException: Cannot bind argument at index 1 because the index is out of range.  The statement has 0 parameters.
            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: Cannot bind argument at index 1 because the index is out of range.  The statement has 0 parameters.
            at android.database.sqlite.SQLiteProgram.bind(SQLiteProgram.java:212)
            at android.database.sqlite.SQLiteProgram.bindString(SQLiteProgram.java:166)
            at android.database.sqlite.SQLiteProgram.bindAllArgsAsStrings(SQLiteProgram.java:200)
            at android.database.sqlite.SQLiteDirectCursorDriver.query(SQLiteDirectCursorDriver.java:47)
            at android.database.sqlite.SQLiteDatabase.rawQueryWithFactory(SQLiteDatabase.java:1316)
            at android.database.sqlite.SQLiteDatabase.queryWithFactory(SQLiteDatabase.java:1163)
            at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1034)
            at android.database.sqlite.SQLiteDatabase.query(SQLiteDatabase.java:1202)
            at com.ms.t.tms.SQLiteDataBaseAdapter.getTask1(SQLiteDataBaseAdapter.java:143)
            at com.ms.t.tms.EditScreen.onCreate(EditScreen.java:70)
            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)

我在一行中共有9列，包括_id作为我尝试根据_id查询的第一列，我最终得到了这个错误。请帮我。我能够插入记录，将记录显示为列表，读取插入记录的详细信息，但是当我尝试编辑这些记录时，我遇到了这个问题。当我将null传递给所有参数时，我总是得到第一行表。请提供建议。如果需要更多信息，请与我们联系。提前谢谢。

Answer 1

您的selection参数应该像

String selection = SQLiteHelper.UID + " = ?";

需要?来定义占位符，其中SQLite将绑定selectionArgs的值。

您已从这里提供的答案中混合并匹配您的代码选择代码段。那不行。将整个方法更改为

public Task getTask1(String id) {

    db = helper.getReadableDatabase();

    String[] columns = { SQLiteHelper.UID, SQLiteHelper.TASK_NAME,
            SQLiteHelper.CONTACTS, SQLiteHelper.DESCRIPTION,
            SQLiteHelper.REMARKS, SQLiteHelper.DATETIME,
            SQLiteHelper.ESTIMATED_COMPLETION_TIME,
            SQLiteHelper.ACTUAL_COMPLETION_TIME, SQLiteHelper.NOTIFY_TIME };

    String selection = SQLiteHelper.UID + " = ?"; // MISSING in your update!!
    String[] selectionArgs = new String[] { id };

    Cursor cursor = db.query(SQLiteHelper.TABLE_NAME, columns, selection,
            selectionArgs, null, null, null);

    if (cursor != null && cursor.moveToFirst()) {
        task = new Task(cursor.getString(1), cursor.getString(2),
                cursor.getString(3), cursor.getString(4),
                cursor.getString(5), cursor.getString(6),
                cursor.getString(7), cursor.getString(8));
        Log.d("Pana", "The value of Task is" + task);
        cursor.close();
    }
    return task;
}

Answer 2

这可能会有所帮助：

    public Task getTask1(String id) {


        db = helper.getReadableDatabase();

        String selection = SQLiteHelper.UID;

        String[] columns = { SQLiteHelper.UID,
                SQLiteHelper.TASK_NAME, SQLiteHelper.CONTACTS, SQLiteHelper.DESCRIPTION, SQLiteHelper.REMARKS, SQLiteHelper.DATETIME, SQLiteHelper.ESTIMATED_COMPLETION_TIME,
                SQLiteHelper.ACTUAL_COMPLETION_TIME, SQLiteHelper.NOTIFY_TIME};


        String[] selectionArgs = new String[]{id};

        Cursor cursor = db.rawQuery("select * from " + SQLiteHelper.TABLE_NAME + "  where _id = ?", selectionArgs);

        if (cursor != null && cursor.moveToFirst()) {

            task = new Task(
                    cursor.getString(1), cursor.getString(2), cursor.getString(3), cursor.getString(4), cursor.getString(5),
                    cursor.getString(6), cursor. getString(7), cursor.getString(8));

            Log.d("Pana", "The value of Task is" + task);

        cursor.close(); //Don't forget to close your cursor, otherwise you will have a memory leak!
        }


        return task;
    }

无法绑定索引1处的参数，因为索引超出范围。该语句有0个参数。＆＃34;

2 个答案: