我想在广播触发时使用加载器管理器及其在广播接收器内的回调

Question

我无法获得getSupportLoaderManger或getLoaderManager

我很困惑如何解决这个问题，

public class MyBroadCastReceiver extends BroadcastReceiver implements LoaderManager.LoaderCallbacks<Cursor> {
    int cpValue;
    private CursorLoader cursorLoader;
    private Context mContext;
    @Override
    public void onReceive(Context context, Intent intent) {
        mContext = context;
        mContext.getSupportLoaderManager().initLoader(1, null, context);
    }
    private void doTheTask(MyAsync task, Intent intent) {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
            // Android 4.4 (API 19) and above
            task.execute(intent);
        } else {
            // Android 3.0 to Android 4.3
            task.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, intent);
        }
    }
    @Override
    public Loader<Cursor> onCreateLoader(int arg0, Bundle arg1) {
        cursorLoader = new CursorLoader(mContext, Uri.parse("content://com.MyApplication.Provider/cte"), null, null, null, null);
        return cursorLoader;
    }
    @Override
    public void onLoadFinished(Loader<Cursor> arg0, Cursor cursor) {
        if (cursor != null) {
            cursor.moveToFirst();
            String res = "0";
            while (!cursor.isAfterLast()) {
                res = cursor.getString(cursor.getColumnIndex("present"));
                cursor.moveToNext();
            }
            cpValue = Integer.valueOf(res);
        } else {
            cpValue = 0;
        }
    }
    @Override
    public void onLoaderReset(Loader<Cursor> arg0) {
    }
}

我的问题是那么我如何在 broadCast 中使用加载器管理器，它在活动和片段中工作正常。

如何在 broadCast Receiver 中使用 LoaderManager？

Answer 1

请看 https://developer.android.com/reference/android/app/LoaderManager.html

加载器管理器仅用于活动和片段

Answer 2

为此，

您可以进行透明活动。

清单.xml

<activity
    android:name=".activity.TransparentActivity"
    android:theme="@style/Theme.Transparent">
</activity>

风格.xml

<style name="Theme.Transparent" parent="android:Theme">
    <item name="android:windowIsTranslucent">true</item>
    <item name="android:windowBackground">@android:color/transparent</item>
    <item name="android:windowContentOverlay">@null</item>
    <item name="android:windowNoTitle">true</item>
    <item name="android:windowIsFloating">true</item>
    <item name="android:backgroundDimEnabled">false</item>
</style>

透明活动.java

import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.LoaderManager;
import android.support.v4.content.CursorLoader;
import android.support.v4.content.Loader;
import android.support.v7.app.AppCompatActivity;
public class TransparentActivity extends AppCompatActivity implements LoaderManager.LoaderCallbacks<Cursor> {
    private CursorLoader cursorLoader;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        getSupportLoaderManager().initLoader(1, null, this);
    }
    @Override
    public Loader<Cursor> onCreateLoader(int arg0, Bundle arg1) {
        cursorLoader = new CursorLoader(this, Uri.parse("content://com.example.yourprovider/cte"), null, null, null, null);
        return cursorLoader;
    }
    @Override
    public void onLoadFinished(Loader<Cursor> arg0, Cursor cursor) {
        if (cursor != null) {
           //Do your stuff
        } 
        finish();
    }
    @Override
    public void onLoaderReset(Loader<Cursor> arg0) {
    }
}

因此，您将从广播中调用此活动，它将更新

Intent newIntent = new Intent(context,TransparentActivity.class);
newIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP); 
newIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(newIntent);

所以这将解决你的问题，我希望如此

这一些如何间接的方式来实现