Part 2 – Configuration Activity

[embedyt] https://www.youtube.com/watch?v=C7IW49jejUY[/embedyt]

In part 2 of the app widget tutorial, we add a configuration activity to our app, which starts when our widget is dragged onto the homescreen and where we can do an initial setup. We get our appWidgetId from the intent with the AppWidgetManager.EXTRA_APPWIDGET_ID key and can then make changes to this widget with help of the RemoteViews class. We will give the user the option to set his own button text and as in the last video we set a PendingIntent to our button which will open our MainActivity when clicked. We will also save the button text to SharedPreferences and then finish our activity with RESULT_OK and pass the appWidgetId back. In case we don’t get passed a valid id, our appWidgetId will be set to AppWidgetManager.INVALID_APPWIDGET_ID.
In our AppWidgetProvider class we retrieve the button text from shared preferences in our onUpdate method and reset it together with the pending intent to our button.
In our AndroidManifest.xml file we have to set the android.appwidget.action.APPWIDGET_CONFIGURE intent filter for our config activity and in the info xml file we have to add the android:configure attribute.

Show less

activity_example_app_widget_config.xmlExampleAppWidgetConfig.javaexample_widget.xmlExampleAppWidgetProvider.javaexample_appwidget_info.xmlAndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="center_horizontal"
    android:orientation="vertical"
    tools:context="com.codinginflow.widgetexample.ExampleAppWidgetConfig">

    <EditText
        android:id="@+id/edit_text_button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="16dp"
        android:hint="Button text" />

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="confirmConfiguration"
        android:text="Confirm" />

</LinearLayout>

package com.codinginflow.widgetexample;

import android.app.PendingIntent;
import android.appwidget.AppWidgetManager;
import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.RemoteViews;

public class ExampleAppWidgetConfig extends AppCompatActivity {
    public static final String SHARED_PREFS = "prefs";
    public static final String KEY_BUTTON_TEXT = "keyButtonText";

    private int appWidgetId = AppWidgetManager.INVALID_APPWIDGET_ID;
    private EditText editTextButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_example_app_widget_config);

        Intent configIntent = getIntent();
        Bundle extras = configIntent.getExtras();
        if (extras != null) {
            appWidgetId = extras.getInt(AppWidgetManager.EXTRA_APPWIDGET_ID,
                    AppWidgetManager.INVALID_APPWIDGET_ID);
        }

        Intent resultValue = new Intent();
        resultValue.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId);
        setResult(RESULT_CANCELED, resultValue);

        if (appWidgetId == AppWidgetManager.INVALID_APPWIDGET_ID) {
            finish();
        }

        editTextButton = findViewById(R.id.edit_text_button);
    }

    public void confirmConfiguration(View v) {
        AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(this);

        Intent intent = new Intent(this, MainActivity.class);
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, 0);

        String buttonText = editTextButton.getText().toString();

        RemoteViews views = new RemoteViews(this.getPackageName(), R.layout.example_widget);
        views.setOnClickPendingIntent(R.id.example_widget_button, pendingIntent);
        views.setCharSequence(R.id.example_widget_button, "setText", buttonText);

        appWidgetManager.updateAppWidget(appWidgetId, views);

        SharedPreferences prefs = getSharedPreferences(SHARED_PREFS, MODE_PRIVATE);
        SharedPreferences.Editor editor = prefs.edit();
        editor.putString(KEY_BUTTON_TEXT + appWidgetId, buttonText);
        editor.apply();

        Intent resultValue = new Intent();
        resultValue.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId);
        setResult(RESULT_OK, resultValue);
        finish();
    }
}

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button
        android:id="@+id/example_widget_button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:text="Press me" />

</RelativeLayout>

package com.codinginflow.widgetexample;

import android.app.PendingIntent;
import android.appwidget.AppWidgetManager;
import android.appwidget.AppWidgetProvider;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.widget.RemoteViews;

import static com.codinginflow.widgetexample.ExampleAppWidgetConfig.KEY_BUTTON_TEXT;
import static com.codinginflow.widgetexample.ExampleAppWidgetConfig.SHARED_PREFS;


public class ExampleAppWidgetProvider extends AppWidgetProvider {

    @Override
    public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
        for (int appWidgetId : appWidgetIds) {
            Intent intent = new Intent(context, MainActivity.class);
            PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, 0);

            SharedPreferences prefs = context.getSharedPreferences(SHARED_PREFS, Context.MODE_PRIVATE);
            String buttonText = prefs.getString(KEY_BUTTON_TEXT + appWidgetId, "Press me");

            RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.example_widget);
            views.setOnClickPendingIntent(R.id.example_widget_button, pendingIntent);
            views.setCharSequence(R.id.example_widget_button, "setText", buttonText);

            appWidgetManager.updateAppWidget(appWidgetId, views);
        }
    }
}

<?xml version="1.0" encoding="utf-8"?>
<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
    android:configure="com.codinginflow.widgetexample.ExampleAppWidgetConfig"
    android:initialLayout="@layout/example_widget"
    android:minHeight="40dp"
    android:minResizeWidth="40dp"
    android:minWidth="110dp"
    android:previewImage="@drawable/widget_preview"
    android:resizeMode="vertical|horizontal"
    android:updatePeriodMillis="3600000"
    android:widgetCategory="home_screen">

</appwidget-provider>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.codinginflow.widgetexample">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity
            android:name=".MainActivity"
            android:launchMode="singleTop">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

        <receiver android:name=".ExampleAppWidgetProvider">
            <intent-filter>
                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
            </intent-filter>

            <meta-data
                android:name="android.appwidget.provider"
                android:resource="@xml/example_appwidget_info" />
        </receiver>

        <activity android:name=".ExampleAppWidgetConfig">
            <intent-filter>
                <action android:name="android.appwidget.action.APPWIDGET_CONFIGURE" />
            </intent-filter>
        </activity>
    </application>

</manifest>