使用SQLite在recyclerView中顯示字符串數組

Question

我創建了一個SQLite數據庫並在其中存儲了字符串，並希望它在recyclerView內的textview中顯示。我應該如何初始化數組？

DatabaseHelper：

public class DatabaseHelper extends SQLiteOpenHelper { 

    public static final String DATABASE_NAME = "Student.db"; 
    public static final String TABLE_NAME = "student_table"; 
    public static final String Col_1 = "ID"; 
    public static final String Col_2 = "Title"; 
    public static final String Col_3 = "Content"; 
    public static final String Col_4 = "Remarks"; 


    public DatabaseHelper(Context context) { 
     super(context, DATABASE_NAME, null, 1); 
     SQLiteDatabase db = this.getWritableDatabase(); 
    } 

    @Override 
    public void onCreate(SQLiteDatabase db) { 
     db.execSQL("create table " +TABLE_NAME+"(ID INTEGER PRIMARY KEY AUTOINCREMENT, Title TEXT, Content TEXT, Remarks TEXT)"); 

    } 

    @Override 
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { 
     db.execSQL("DROP TABLE IF EXISTS"+TABLE_NAME); 

    } 
} 

，這是我的初始化cardView：

private void initializeCardItemList(){ 
     CardItemModel cardItemModel; 
     /*String[] cardTitles = getResources().getStringArray(R.array.cat1_cards); 
     String[] cardContents = getResources().getStringArray(R.array.cat1_cards_content); */ 
     final int length = cardTitles.length; 
     for(int i=0;i<length;i++){ 
      cardItemModel = new CardItemModel(cardTitles[i],cardContents[i]); 
      cardItems.add(cardItemModel); 
     } 
    } 

Answer 1

初始化這裏：

DatabaseHelper=new DataBaseAdapter(...);// initialize here 
    recyclerView.setAdapter(new RecycleViewAdapter(
       DataBaseHelper.getData(),R.layout.rec_layout)); 

Answer 2

假定您使用SQLiteDatabase.query()查詢從琴絃數據庫。你可以做到這一點因此在你初始化C：

ArrayList<String> mStrings = new ArrayList<>(); 
while (mCursor.moveToNext()) { 
    int columnIndex = cursor.getColumnIndex("column_name"); 
    mStrings.add(cursor.getString(columnIndex); 
} 

這將增加所有字符串內mCursor到mStrings。您可以使用ArrayList<>.get()方法訪問字符串。

編輯：然後，您可以通過RecyclerView.Adapter構造函數傳遞ArrayList<String>對象並設定它由TextView期間RecyclerView.Adapter.onBindViewHolder()顯示。

Answer 3

https://developer.android.com/training/basics/data-storage/databases.html是解釋這一切的官方文檔。