java - 如何使用 Arraylist 将 Sqlite Adapter 类访问到 MainActivity？

Question

我正在创建一个示例图库应用程序，我正在尝试将图库项目存储在本地 sqlite 数据库中

Adapter.class 的方法:

    public List<String> getImagePath()
{
    ArrayList<String> paths = new ArrayList<String>();
    String selectQuery = "SELECT * FROM " + Databaseconnect.TABLE_FILE;
    SQLiteDatabase db = dbHelper.getWritableDatabase();
    Cursor cursor = db.rawQuery(selectQuery, null);
    // looping through all rows and adding to list
    if (cursor.moveToFirst())
    {
        do {

            paths.add(cursor.getString(3).toString());
 //                Log.d("getPathImage:", cursor.getString(0).toString());
        } while (cursor.moveToNext());
    }

    return paths;
}

比

    MuAdapter= new muadapter(Activityname.this);
    mudapter.open();
    ArrayList<String> list =getImagePath();

但是我有一个错误

    ArrayList<String> list =getImagePath();

如何初始化这个方法？请给我一个解决方案。

Answer 1

MuAdapter= new muadapter(Activityname.this);
//  this line is broke. Use something like "MuAdapter muAdapter = new ..." 

mudapter.open();
// then this line can work

ArrayList<String> list =getImagePath();
// not sure about this, but don't you need an objectrefernece here, that you call getImagePath() on?!