Creating an External App

This documentation assumes that you are using Android Studio and developing your app in Java. To launch the app refer to

See also

Launching Apps from a Survey

Create Project

• In Android Studio click on the menu "File" -> "New" -> "New Project"

• Select "Empty Views Activity"

• Specify Java as the language and set the project name etc.

• Click "Finish"

Add an Activity that responds to an Intent from FieldTask

Add an activity to the project, for example MainActivity, and in AndroidManifest.xml give it an intent filter with an action name of your own choosing:

<activity
    android:name=".MainActivity"
    android:exported="true">
    <intent-filter>
        <action android:name="org.example.myapp.GET_VALUE" />
        <category android:name="android.intent.category.DEFAULT" />
    </intent-filter>
</activity>

The action name is what goes after ex: in the appearance of the question, for example ex:org.example.myapp.GET_VALUE(type='text'). android:exported="true" is required so that fieldTask can start the activity.

In onCreate, of the activity, get any parameters passed from fieldTask:

Intent intent = getIntent();
String type = intent.getStringExtra("type");   // Get the value of parameter "type"

Then your activity can do its magic and get a value to return. So at the end of onCreate return this value to fieldTask. Case 1 returning a text value:

Intent returnIntent = new Intent();
returnIntent.putExtra("value", "The text value to be returned");
setResult(Activity.RESULT_OK, returnIntent);
finish();

Case 2 returning an image, for a question of type image. Save the image to a file, share it through a FileProvider and return its URI in the clip data of the result:

Uri uri = FileProvider.getUriForFile(this, "org.example.myapp.fileprovider", imageFile);
Intent returnIntent = new Intent();
returnIntent.setClipData(ClipData.newRawUri("image.png", uri));
returnIntent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
setResult(Activity.RESULT_OK, returnIntent);
finish();

The FileProvider has to be declared in the manifest with android:grantUriPermissions="true" so that fieldTask is allowed to read the file.