How to interact with USSD dialog programmatically in android
<p>I want to use <strong>USSD dialog</strong> which comes after dialing any <strong>USSD code</strong> say <strong>*123#</strong> which asks user to enter option number to perform specific task(s) depending upon sim card vendors. I need to interact with that dialog to provide input in the text box given into it programmatically.</p>

<p>However, I am able to read the <strong>USSD response</strong> that comes in Alert Dialog after dialing any USSD code, using <code>AccessibilityService</code> and I'm showing the response in a <code>Toast</code> as shown in the code below. I haven't found any solution to interact with USSD dialog yet.</p>

<pre><code>public class UssdService extends AccessibilityService{
    public static String TAG = "USSD";

    @Override
    public void onAccessibilityEvent(AccessibilityEvent event) {
        Log.d(TAG, "onAccessibilityEvent");
        String text = event.getText().toString();
        if (event.getClassName().equals("android.app.AlertDialog")) {
            Log.d(TAG, text);
            Toast.makeText(this, text, Toast.LENGTH_LONG).show();
        }
    }

    @Override
    public void onInterrupt() {
    }

    @Override
    protected void onServiceConnected() {
        super.onServiceConnected();
        Log.d(TAG, "onServiceConnected");
        AccessibilityServiceInfo info = new AccessibilityServiceInfo();
        info.flags = AccessibilityServiceInfo.DEFAULT;
        info.packageNames = new String[]{"com.android.phone"};
        info.eventTypes = AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED;
        info.feedbackType = AccessibilityServiceInfo.FEEDBACK_GENERIC;
        setServiceInfo(info);
    }
}
</code></pre>

<p>Here is the service declaration in Manifest:</p>

<pre><code>&lt;service android:name=".UssdService"
    android:permission="android.permission.BIND_ACCESSIBILITY_SERVICE"&gt;
    &lt;intent-filter&gt;
        &lt;action android:name="android.accessibilityservice.AccessibilityService" /&gt;
    &lt;/intent-filter&gt;
    &lt;meta-data android:name="android.accessibilityservice"
        android:resource="@xml/config_service" /&gt;
&lt;/service&gt;
</code></pre>