Android: Crash when setting up media route button

Question

I'm having pretty much the same problem as Android: Cast SDK v3 Crashing in Release build only. The key difference is that my project does it while i'm just debugging and does it on this line

CastButtonFactory.setUpMediaRouteButton(getApplicationContext(), mMediaRouteButton);

I have tried making all my variables public but that doesn't do anything. The full code is

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    mMediaRouteButton = (MediaRouteButton) findViewById(R.id.media_route_button);
    CastButtonFactory.setUpMediaRouteButton(getApplicationContext(), mMediaRouteButton);

    mCastContext = CastContext.getSharedInstance(this);

    mSelector = new MediaRouteSelector.Builder()
            // These are the framework-supported intents
            .addControlCategory(MediaControlIntent.CATEGORY_LIVE_AUDIO)
            .addControlCategory(MediaControlIntent.CATEGORY_LIVE_VIDEO)
            .addControlCategory(MediaControlIntent.CATEGORY_REMOTE_PLAYBACK)
            .build();
    mMediaRouter = MediaRouter.getInstance(this);
}

Also I find it worth mentioning that this code worked and I can not for the life of me figure out what caused it to stop working. As far as I can tell it stopped working when I invalidated the cache in Android Studio. This is the error I'm getting

java.lang.RuntimeException: Unable to start activity ComponentInfo{mypackage.package/mypackage.package.MainActivity}: java.lang.IllegalStateException: Failed to initialize CastContext.
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2646)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
    at android.app.ActivityThread.-wrap12(ActivityThread.java)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:154)
    at android.app.ActivityThread.main(ActivityThread.java:6077)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755)
    Caused by: java.lang.IllegalStateException: Failed to initialize CastContext.
    at com.google.android.gms.cast.framework.CastContext.zzbb(Unknown Source)
    at com.google.android.gms.cast.framework.CastContext.getSharedInstance(Unknown Source)
    at com.google.android.gms.cast.framework.CastButtonFactory.setUpMediaRouteButton(Unknown Source)
    at mypackage.package.MainActivity.onCreate(MainActivity.java:51)
    at android.app.Activity.performCreate(Activity.java:6664)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2599)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707) 
    at android.app.ActivityThread.-wrap12(ActivityThread.java) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460) 
    at android.os.Handler.dispatchMessage(Handler.java:102) 
    at android.os.Looper.loop(Looper.java:154) 
    at android.app.ActivityThread.main(ActivityThread.java:6077) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755) 
    Caused by: java.lang.IllegalAccessException: java.lang.Class<mypackage.package.CastOptionsProvider> is not accessible from java.lang.Class<com.google.android.gms.cast.framework.CastContext>
    at java.lang.Class.newInstance(Native Method)
    at com.google.android.gms.cast.framework.CastContext.zzbb(Unknown Source) 
    at com.google.android.gms.cast.framework.CastContext.getSharedInstance(Unknown Source) 
    at com.google.android.gms.cast.framework.CastButtonFactory.setUpMediaRouteButton(Unknown Source) 
    at mypackage.package.MainActivity.onCreate(MainActivity.java:51) 
    at android.app.Activity.performCreate(Activity.java:6664) 
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118) 
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2599) 
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707) 
    at android.app.ActivityThread.-wrap12(ActivityThread.java) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460) 
    at android.os.Handler.dispatchMessage(Handler.java:102) 
    at android.os.Looper.loop(Looper.java:154) 
    at android.app.ActivityThread.main(ActivityThread.java:6077) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:865) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:755) 

Answer 1

If this is happening only in release buildtype then it is related to proguard. Please add the CastOptionsProvider class to the proguard file and recheck

-keep class abc.xyz.videocast.CastOptionsProvider { *; }

For more safety these classes can also be added

-keep class android.support.** { *; }
-keep class com.google.** { *; }

Answer 2

This was fixed by making the CastOptionsProvider public. I don't know why this problem occurred to begin with, because it was working fine when it wasn't public until it didn't. I didn't touch the CastOptionsProvider on the build where it started failing. My CastOptionsProvider now looks like this

public class CastOptionsProvider implements OptionsProvider {
 @Override
 public CastOptions getCastOptions(Context appContext) {
     CastOptions castOptions = new CastOptions.Builder()
            .setReceiverApplicationId(appContext.getString(R.string.app_id))
            .build();
     return castOptions;
 }
 @Override
 public List<SessionProvider> getAdditionalSessionProviders(Context context) {
    return null;
 }
}

Answer 3

There might be an issue on how you initialize media CastContext, to properly initialize CastContext, the application must have the implements OptionsProvider interface:

package com.example.app;

 public class CastOptionsProvider implements OptionsProvider {
     @Override
     public CastOptions getCastOptions(Context appContext) {
         ...
     }
 }

and specify its fully qualified class name in the AndroidManifest.xml with the key OPTIONS_PROVIDER_CLASS_NAME_KEY:

  ...
     <meta-data
         android:name="com.google.android.gms.cast.framework.OPTIONS_PROVIDER_CLASS_NAME"
         android:value="com.example.app.CastOptionsProvider" />
     ...

Note: All public methods must be called from the main thread.

I did some research and found this related SO ticket which discuss how to initialize CastContext: How to initialize CastContext outside of onCreate method