accessibility service is not started

Question

I want to log all toasts events in android ics (4.0.3), but I was unable to log any system event. Service is just not started!

According to this question: onAccessibilityEvent(AccessibilityEvent event) not intercepting notification

MyAccessibilityService.java

package com.test.toasts2;

import android.accessibilityservice.AccessibilityService;
import android.accessibilityservice.AccessibilityServiceInfo;
import android.app.Notification;
import android.os.Parcelable;
import android.util.Log;
import android.view.accessibility.AccessibilityEvent;
import android.widget.Toast;

public class MyAccessibilityService extends AccessibilityService {


    public static final String TAG = "volumeMaster";

    @Override
    public void onAccessibilityEvent(AccessibilityEvent event)
    {
        Log.v(TAG, "***** onAccessibilityEvent");
        Toast.makeText(getApplicationContext(), "Got event from: " + event.getPackageName(), Toast.LENGTH_LONG).show();
    }

    @Override
    public void onInterrupt()
    {
        Log.v(TAG, "***** onInterrupt");
    }

    @Override
    public void onServiceConnected()
    {
        Log.v(TAG, "***** onServiceConnected");       


        AccessibilityServiceInfo info = new AccessibilityServiceInfo();
        info.eventTypes = AccessibilityEvent.TYPE_NOTIFICATION_STATE_CHANGED;
        info.notificationTimeout = 100;
        info.feedbackType = AccessibilityEvent.TYPES_ALL_MASK;
        setServiceInfo(info);

    }
}

Toast2Activity.java

package com.test.toasts2;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.Toast;

public class Toast2Activity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Intent i = new Intent(this, MyAccessibilityService.class);
        startService(i);
    }
}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.test.toasts2"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk android:minSdkVersion="15" />

    <application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name" >
<service android:name=".MyAccessibilityService" android:label="@string/app_name" android:enabled="true" android:exported="false">
        <intent-filter>
            <action android:name="android.accessibilityservice.AccessibilityService" />
        </intent-filter>

</service>

        <activity
            android:name=".Toast2Activity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

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

</manifest>

I included activity tag in manifest (to start service on app start), and also tried to remove. Nothing changed. Service is just not started. I don't get notification in log cat (Log.v in onServiceConected).

I am compiling this as normal app (not system app), android 4.0.3. Am I doing something wrong?

Attached project (may be mistake is somewhere else, or maybe I am compiling it wrong): https://dl.dropbox.com/u/1928109/toast2.zip

Answer 1

You need to enable the accessibility service from the system settings menu:

• Install your app on the testing device.

• With the app installed on the device, change the following setting on the device:

  Home Screen > System Settings > Accessibility > Accessibility Services > Toast2 > Change from Off to On,

  where Toast2 is your app name.

• Then run your app.

AFAIK there is no method to set accessibility programmatically to On mode from within your app. As a workaround you can prompt the user to change the setting and if they agree by clicking a button, launch the accessibility system settings like so:

Intent intent = new Intent(android.provider.Settings.ACTION_ACCESSIBILITY_SETTINGS);
startActivityForResult(intent, 0);

Answer 2

As a complementary answer to the comments, one more thing worth noting is that you have to declare permission - android:permission="android.permission.BIND_ACCESSIBILITY_SERVICE" in your service, or else there will be no switch in setting->accessibility.