Question

I’m trying to create a default handler for .p7s/.p7b files in Android.

I figured the best start would be to create a BroadcastReceiver that will capture the intent from the Android email application (or K-9 if that’s a need) for opening of certain attachments (filtered by mime type). Specifically I’m trying to handle s/mime email so looking for the “application/x-pkcs7-certificates” and “application/x-pkcs7-certificates” mime types.

Just as a basic test I’ve been trying something like this:

Manifest.xml

<receiver android:name=".IntentReceiver" android:enabled="true">
     <intent-filter>
            <action android:name="android.intent.action.VIEW" />
            <category android:name="android.intent.category.DEFAULT" />
            <category android:name="android.intent.category.BROWSABLE" />
            <data android:mimeType="application/x-pki-signature"/>
     </intent-filter>
</receiver>

Class file.

public class IntentReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
        Log.d("TEST", "Intent was caught");
        //Do something here
    }
}

I’ve tried using the following mimeType filters as well (testing signatures first):

application/pkcs7-signature
application/x-pkcs7-signature
application/keychain_access

I can’t seem to get the IntentReceiver class to capture the intent no matter what filtering I use though. Am I going about this the wrong way?

Answer 1

FIXED: I tried to simply use a regular activity and add the mimeType filtering into that and BAM! it worked. Seems there must be a discrepancies with the BroadcastReceiver not supporting this type of VIEW intent.

New manifest:

<activity android:name=".PkixReceiver"
          android:label="@string/app_name">
    <intent-filter>
        <category android:name="android.intent.category.DEFAULT" />
        <action android:name="android.intent.action.VIEW" />
        <data android:mimeType="application/x-pkcs7-signature" />
        <data android:mimeType="application/pkcs7-signature" />
        <data android:mimeType="application/keychain_access" /> 
    </intent-filter>
</activity>

And now the activity gets fired when the “open” attachment is clicked, success!