Kivy Android Intent Filters

Intent filters are Android’s equivalent of file associations.  When you click on a file in a file manager on Android it starts the associated application by using an intent.  Applications can support the emission of intents with different categories.  Other apps which have registered to receive intents of that category can then receive and process them.

In order to make use of these intents from Kivy/buildozer you need to add an intent-filter to your a file (by default called intent_filters.xml) in your app’s root directory.  You also need to edit the buildozer.spec file to point to the file (look for this line and uncomment):

# (str) XML file to include as an intent filters in <activity> tag
android.manifest.intent_filters=intent_filters.xml

The intent filter will differ depending on the intent.  Intents based on mimetypes are better than those based on paths.  Apparently there’s a problem with Android’s file search algorithm so you need to specify every relevant directory level if you want to filter on the file’s extension (seriously!).  Sample intent (from my art gridder app, which uses files with a .bag extension:

<intent-filter>
<action android:name=”android.intent.action.VIEW” />
<category android:name=”android.intent.category.DEFAULT” />
<data android:mimeType=”*/*” />
<data android:scheme=”file” />
<data android:host=”*” />
<data android:port=”*” />
<data android:pathPattern=”.*..*..*..*..*.bag” />
<data android:pathPattern=”.*..*..*..*.bag” />
<data android:pathPattern=”.*..*..*.bag” />
<data android:pathPattern=”.*..*.bag” />
<data android:pathPattern=”.*.bag” />
</intent-filter>

Finally, your app needs to be able to receive and extract the intent (don’t expect to find this in the docs!):

if __name__ == "__main__":
    if platform=="android":
        from jnius import cast
        from jnius import autoclass
        import android
        import android.activity

        # test for an intent passed to us
        PythonActivity = autoclass('org.renpy.android.PythonActivity')
        activity = PythonActivity.mActivity
        intent = activity.getIntent()
        intent_data = intent.getData()
        try:
            file_uri= intent_data.toString()
        except AttributeError:
            file_uri = None

Then pass the file uri to the app when you instantiate it.