Code Demo for intercepting

AndroidManifest.xml

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

    <application
        android:allowBackup="false"
        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">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>

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

            <intent-filter>
                <action android:name="org.thialfihar.android.apg.intent.DECRYPT_AND_RETURN"/>

                <category android:name="android.intent.category.DEFAULT"/>
                <data android:mimeType="*/*"/>
            </intent-filter>
        </activity>
    </application>

</manifest>

MainActivity.java

package com.elliecoding.decrypttester;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;

public class MainActivity extends AppCompatActivity {

    private static final String TAG = MainActivity.class.getName();
    private static final String DECRYPT_AND_RETURN_ACTION = "org.thialfihar.android.apg.intent.DECRYPT_AND_RETURN";
    private static final String EXTRA_TEXT = "text";

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

        handleActions(getIntent());

        returnResult();
        finish();
    }

    private void returnResult() {
        Intent intent = new Intent();

        intent.putExtra("signatureUserId", "user");
        intent.putExtra("signatureKeyId", "keyId");
        intent.putExtra("signatureSuccess", true);
        intent.putExtra("signatureUnknown", false);
        intent.putExtra("decryptedMessage", "Look ma I decrypted this text");

        setResult(RESULT_OK, intent);
    }

    private void handleActions(Intent intent) {
        String action = intent.getAction();
        Bundle extras = intent.getExtras();
        if (extras == null) {
            extras = new Bundle();
        }

        String textData = extras.getString(EXTRA_TEXT);


        Log.i(TAG, "Action is: " + action);

        if (DECRYPT_AND_RETURN_ACTION.equals(action)) {
            Log.e(TAG, textData);
        }
    }
}