Android CursorLoader，ContentProvider太慢了

我有一个计数器应用程序，我使用过

SimpleCursorAdapter

，

ListView

和

StartManagingCursor（）

。现在我想使用新的

CursorLoader

和

Contentprovider

。我编写了自己的

ContentProvider

，并在

MainActivity

上实现了它。正如你们可以看到我的应用程序上面，当我点击加号按钮和更新计数，它是滞后的。我大约每秒点击2次，但它不能处理得很快。我使用

ContentResolver

进行更新

以前的方法是快速启动管理游标

代码在这里，如果我在ContentProvider或CursorLoader上有任何错误，请帮助我

MAIN.java

public class Main extends ActionBarActivity implements LoaderCallbacks<Cursor> {
    Cursor cursor;
    String[] FROM = { Database.C_NAME, Database.C_VALUE };// get values from db
    int[] TO = { R.id.textMainName, R.id.textMainValue };// set values of item


    SimpleCursorAdapter adapter;
    boolean clickP;
    boolean clickN;
    boolean clickR;
    String Lng;


    private static final int URL_LOADER = 0;
    private ListView mListView;
    private ChannelAdapter mAdapter ;

    ContentResolver cr ;

    @SuppressWarnings("deprecation")
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        mListView = (ListView) findViewById(R.id.list);            

        mAdapter =new ChannelAdapter(this, R.layout.list_item,null, FROM, TO,0);            
        mListView.setAdapter(mAdapter);         
           getSupportLoaderManager().initLoader(URL_LOADER, null, this);   

        registerForContextMenu(mListView);
            }

    @Override
    protected void onResume() {

        getSupportLoaderManager().restartLoader(0, null, this); }

    public class ChannelAdapter extends SimpleCursorAdapter {
        @SuppressWarnings("deprecation")
        public ChannelAdapter(Context context, int layout, Cursor c,
                String[] from, int[] to,int flag) {
            super(context, layout, c, from, to, flag);
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {

            LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.list_item, parent, false);


            Button bP = (Button) convertView.findViewById(R.id.buttonMainPlus);

            final TextView tvName = (TextView) convertView.findViewById(R.id.textMainName);
            final TextView tvValue = (TextView) convertView.findViewById(R.id.textMainValue);
            // When plus button is clicked
            bP.setOnClickListener(new OnClickListener() {
                @Override
                public void onClick(View v) {                   

                    int valuer = Integer.parseInt(tvValue.getText().toString());

                    ContentValues updatedValues = new ContentValues();
                    updatedValues.put(Database.C_VALUE,valuer+1);
                    //Uri rowURI =ContentUris.withAppendedId(MyContentProvider.CONTENT_URI,hoardId);
                    // Specify a specific row so no selection clause is required.
                    String where = Database.C_NAME+ " = '"  + tvName.getText().toString() + "'" ;
                    String whereArgs[] = null;
                    // Get the Content Resolver.
                    cr = getContentResolver();
                    // Update the specified row.
                    int updatedRowCount = cr.update(MyContentProvider.CONTENT_URI, updatedValues, where, whereArgs);

                }
            });

            return super.getView(position, convertView, parent);
        }
    }

@Override
public Loader<Cursor> onCreateLoader(int loaderID, Bundle bundle) {      
    switch (loaderID) {
        case URL_LOADER:                
            return new CursorLoader(Main.this,MyContentProvider.CONTENT_URI,null,null,null,null);
        default:               
            return null;
    }
}

@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor cursor) {       
    mAdapter.swapCursor(cursor);      
}

@Override
public void onLoaderReset(Loader<Cursor> arg0) {       
    mAdapter.swapCursor(null);
}

}

Database.java

public class Database extends Activity {
    public static final String TAG = "Database";
    public static final String C_ID = BaseColumns._ID;
    //Columns
    public static final String C_NAME = "counterName";
    public static final String C_VALUE = "counterValue";
    public static final String C_ORDER = "counterOrder";
    //Database name, version, table name
    public static final String DB_NAME = "list.db";
    public static final int DB_VERSION = 1; // If you change, it will call onUpgrade()
    public static final String TABLE = "List";

    Context context;
    DbHelper dbHelper;
    SQLiteDatabase db;

    public Database(Context context) {
        this.context = context;
        dbHelper = new DbHelper();
    }

    class DbHelper extends SQLiteOpenHelper {
        public DbHelper() {
            super(context, DB_NAME, null, DB_VERSION);
        }

        @Override
        public void onCreate(SQLiteDatabase db) {
            String sql = String.format("CREATE TABLE %s"
                            + " (%s INTEGER PRIMARY KEY AUTOINCREMENT, %s VARCHAR, %s INT, %s INT)",
                            TABLE, C_ID, C_NAME, C_VALUE, C_ORDER);
            db.execSQL(sql);
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            db.execSQL("drop table if exists " + TABLE);
            onCreate(db);
        }
    }

    public void openDb(){
        db=dbHelper.getWritableDatabase();
    }
    public Cursor query() {
        openDb();
        // iterate over all rows columns on TABLE
        Cursor cursor = db.query(TABLE, null, null, null, null, null, null);
        return cursor;
    }




}

---

我已经更改了

ChannelAdapter

，为了像这样膨胀列表项，我开始使用

ViewHolder

，它将速度提高了大约%15-18（我从某个地方读到过），

findViewById

花费大量时间来查找资源并膨胀每个项

慢的部分是

int updatedRowCount=cr.update（MyContentProvider.CONTENT\u URI，updatedValues，where，wherergs），它调用内容提供程序的更新方法。我尝试将ContentProvider的更新方法更改为普通SQL查询。仍然很慢，但是如果我从MainActivity调用SQL查询，它就可以了。所以我看到LoaderCallbacks是异步工作的，一秒钟内更新屏幕两次很慢。我再次使用StartManagingCursor（），我很高兴：）让您尝试使用前面提到的
AsyncQueryHandler
public class Database extends Activity {
    public static final String TAG = "Database";
    public static final String C_ID = BaseColumns._ID;
    //Columns
    public static final String C_NAME = "counterName";
    public static final String C_VALUE = "counterValue";
    public static final String C_ORDER = "counterOrder";
    //Database name, version, table name
    public static final String DB_NAME = "list.db";
    public static final int DB_VERSION = 1; // If you change, it will call onUpgrade()
    public static final String TABLE = "List";

    Context context;
    DbHelper dbHelper;
    SQLiteDatabase db;

    public Database(Context context) {
        this.context = context;
        dbHelper = new DbHelper();
    }

    class DbHelper extends SQLiteOpenHelper {
        public DbHelper() {
            super(context, DB_NAME, null, DB_VERSION);
        }

        @Override
        public void onCreate(SQLiteDatabase db) {
            String sql = String.format("CREATE TABLE %s"
                            + " (%s INTEGER PRIMARY KEY AUTOINCREMENT, %s VARCHAR, %s INT, %s INT)",
                            TABLE, C_ID, C_NAME, C_VALUE, C_ORDER);
            db.execSQL(sql);
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            db.execSQL("drop table if exists " + TABLE);
            onCreate(db);
        }
    }

    public void openDb(){
        db=dbHelper.getWritableDatabase();
    }
    public Cursor query() {
        openDb();
        // iterate over all rows columns on TABLE
        Cursor cursor = db.query(TABLE, null, null, null, null, null, null);
        return cursor;
    }




}