Android：使用来自 itemOnSelected Spinner 的行结果 (sqlite) 填充 TextView

Question

我想使用微调器作为菜单，以便能够 select 锻炼的名称，在 selection 上 TextViews (x4) 将被填充与该名称相关的练习。目前，Spinner 正在加载锻炼名称，并且已经将第一个锻炼加载到每个 TextView 的 onCreation。

应用程序启动时没有错误，但是当新锻炼名称为 selected 时，其他行不会加载到 TextViews 中。只能假设我犯了一个错误在逻辑上。

问题：如果是逻辑错误，能否请大神指点一下？

begin.java

    protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_begin);

    loadSpinnerData();
    refreshTextView();



}

   public void loadTextView(){
    DataHelper dataHelper = new DataHelper(this);
    ArrayList<String> exercises = dataHelper.getExercises();



          ((TextView) findViewById(R.id.exercise1)).setText(exercises.get(0));

          ((TextView) findViewById(R.id.exercise2)).setText(exercises.get(1));

          ((TextView) findViewById(R.id.exercise3)).setText(exercises.get(2));

          ((TextView) findViewById(R.id.exercise4)).setText(exercises.get(3));


  }
    public void refreshTextView(){
    Spinner databaseR = (Spinner) findViewById(R.id.databaseR);
    databaseR.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            loadTextView();

        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {
        }
    });

DataHelper.java

  public  String Create_ex="CREATE TABLE ExerciserEasy"
        + " (ID INTEGER PRIMARY KEY AUTOINCREMENT, Workout VARCHAR, ExerciseOne VARCHAR,"
        +"ExerciseTwo VARCHAR, ExerciseThree VARCHAR, ExerciseFour VARCHAR );"

   public ArrayList<String> getExercises(){
    ArrayList<String> list = new ArrayList<String>();
    SQLiteDatabase db = this.getReadableDatabase();
    db.beginTransaction();
    try {
        String selectQuery = " Select * from " + Table_ex1;
        Cursor cursor = db.rawQuery(selectQuery, null);
        if(cursor.moveToFirst()){
            do{
                list.add(cursor.getString(2));
                list.add(cursor.getString(3));
                list.add(cursor.getString(4));
                list.add(cursor.getString(5));
                Log.d("HIITtimer", ""+cursor.getCount());

            }while(cursor.moveToNext());
        }
        db.setTransactionSuccessful();
    }catch (Exception e){
        e.printStackTrace();
    }finally {

        db.endTransaction();
        db.close();


    }
    return list;


}

Answer 1

首先您需要将选定的锻炼名称传递给 loadTextView()，这样您就可以将它传递给 getExercises() 并根据该名称查询数据库，其他代码看起来不错，

1-在getExercises()中添加参数workoutName，在WHERE子句中使用

public ArrayList<String> getExercises(String workoutName){
    //codes ...
    String selectQuery = " Select * from " + Table_ex1 + " WHERE Workout ='" workoutName + "'";
    //codes ...
}

注意：您可能想使用 SQLiteDatabase#query() 而不是行查询？

2-将参数workoutName添加到loadTextView()，并传递给getExercises()：

public void loadTextView(String workoutName){
    //code ...
    ArrayList<String> exercises = dataHelper.getExercises(workoutName);
    //code ...
}

3- 通过微调器 setOnItemSelectedListener():

中选定的锻炼

@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
    loadTextView(databaseR.getSelectedItem().toString());
}

现在当项目被选中时，loadTextView()被调用，告诉方法选择了哪个锻炼，并查询数据库以获取与该锻炼名称相关的记录。

Android：使用来自 itemOnSelected Spinner 的行结果 (sqlite) 填充 TextView

Android: Populate TextView with row results (sqlite) from itemOnSelected Spinner

java

sqlite

android

spinner

textview