Event OnClick for a button in a custom notification

I am writing code in my MyActivity.java class that extends android.app.Activity

It creates a custom notification, when user click on the button it sends a broadcast.
There is a broadcast receiver that receives the broadcast.

private void createDownloadNotification() {
        Intent closeButton = new Intent("Download_Cancelled");
        closeButton.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP);

        PendingIntent pendingSwitchIntent = PendingIntent.getBroadcast(this, 0, closeButton, 0);

        RemoteViews notificationView = new RemoteViews(getPackageName(), R.layout.widget_update_notification);

        NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

        NotificationCompat.Builder builder = new NotificationCompat.Builder(this).setSmallIcon(R.drawable.ic_launcher).setTicker("Ticker Text").setContent(notificationView);
        notificationView.setProgressBar(R.id.pb_progress, 100, 12, false);
        notificationView.setOnClickPendingIntent(R.id.btn_close, pendingSwitchIntent);

        notificationManager.notify(1, builder.build());

    }


public static class DownloadCancelReceiver extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {

            System.out.println("Received Cancelled Event");
        }
    }

Register receiver in AndroidManifest.xml

<receiver android:name=".MainActivity$DownloadCancelReceiver" android:exported="false">
            <intent-filter>
                <action android:name="Download_Cancelled" />
            </intent-filter>
        </receiver>

Since it is inner class so have to use $ sign

Widget xml is here

<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:gravity="center"
    android:orientation="horizontal" >

    <Button
        android:id="@+id/btn_close"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Close Me" />

    <ProgressBar
        android:id="@+id/pb_progress"
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

</LinearLayout>