Android: Decouple SurfaceView initialization and emulation start.

Source/Android/app/src/main/java/org/dolphinemu/dolphinemu/fragments/EmulationFragment.java

@@ -4,7 +4,11 @@ import android.app.Fragment;
 import android.content.SharedPreferences;
 import android.os.Bundle;
 import android.preference.PreferenceManager;
+import android.util.Log;
 import android.view.LayoutInflater;
+import android.view.Surface;
+import android.view.SurfaceHolder;
+import android.view.SurfaceView;
 import android.view.View;
 import android.view.ViewGroup;
 
@@ -14,7 +18,7 @@ import org.dolphinemu.dolphinemu.R;
 import org.dolphinemu.dolphinemu.emulation.overlay.InputOverlay;
 
 
-public final class EmulationFragment extends Fragment
+public final class EmulationFragment extends Fragment implements SurfaceHolder.Callback
 {
 	public static final String FRAGMENT_TAG = BuildConfig.APPLICATION_ID + ".emulation_fragment";
 
@@ -22,8 +26,19 @@ public final class EmulationFragment extends Fragment
 
 	private SharedPreferences mPreferences;
 
+	private SurfaceView mSurfaceView;
+	private Surface mSurface;
+
 	private InputOverlay mInputOverlay;
 
+	private Thread mEmulationThread;
+
+	private String mPath;
+
+	private boolean mEmulationStarted;
+	private boolean mEmulationRunning;
+
+
 	public static EmulationFragment newInstance(String path)
 	{
 		EmulationFragment fragment = new EmulationFragment();
@@ -43,6 +58,9 @@ public final class EmulationFragment extends Fragment
 	{
 		super.onCreate(savedInstanceState);
 
+		// So this fragment doesn't restart on configuration changes; i.e. rotation.
+		setRetainInstance(true);
+
 		mPreferences = PreferenceManager.getDefaultSharedPreferences(getActivity());
 	}
 
@@ -52,14 +70,15 @@ public final class EmulationFragment extends Fragment
 	@Override
 	public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)
 	{
-		String path = getArguments().getString(ARGUMENT_GAME_PATH);
+		mPath = getArguments().getString(ARGUMENT_GAME_PATH);
+		NativeLibrary.SetFilename(mPath);
 
 		View contents = inflater.inflate(R.layout.fragment_emulation, container, false);
 
+		mSurfaceView = (SurfaceView) contents.findViewById(R.id.surface_emulation);
 		mInputOverlay = (InputOverlay) contents.findViewById(R.id.surface_input_overlay);
 
-		NativeLibrary.SetFilename(path);
-
+		mSurfaceView.getHolder().addCallback(this);
 
 		// If the input overlay was previously disabled, then don't show it.
 		if (!mPreferences.getBoolean("showInputOverlay", true))
@@ -67,6 +86,18 @@ public final class EmulationFragment extends Fragment
 			mInputOverlay.setVisibility(View.GONE);
 		}
 
+
+		if (savedInstanceState == null)
+		{
+			mEmulationThread = new Thread(mEmulationRunner);
+		}
+		else
+		{
+			// Likely a rotation occurred.
+			// TODO Pass native code the Surface, which will have been recreated, from surfaceChanged()
+			// TODO Also, write the native code that will get the video backend to accept the new Surface as one of its own.
+		}
+
 		return contents;
 	}
 
@@ -74,21 +105,24 @@ public final class EmulationFragment extends Fragment
 	public void onStart()
 	{
 		super.onStart();
-		NativeLibrary.UnPauseEmulation();
+		startEmulation();
 	}
 
 	@Override
 	public void onStop()
 	{
 		super.onStop();
-		NativeLibrary.PauseEmulation();
+		pauseEmulation();
 	}
 
 	@Override
 	public void onDestroyView()
 	{
 		super.onDestroyView();
-		NativeLibrary.StopEmulation();
+		if (getActivity().isFinishing())
+		{
+			NativeLibrary.StopEmulation();
+		}
 	}
 
 	public void toggleInputOverlayVisibility()
@@ -111,4 +145,78 @@ public final class EmulationFragment extends Fragment
 
 		editor.apply();
 	}
+
+	@Override
+	public void surfaceCreated(SurfaceHolder holder)
+	{
+		Log.d("DolphinEmu", "Surface created.");
+	}
+
+	@Override
+	public void surfaceChanged(SurfaceHolder holder, int format, int width, int height)
+	{
+		Log.d("DolphinEmu", "Surface changed. Resolution: " + width + "x" + height);
+		mSurface = holder.getSurface();
+	}
+
+	@Override
+	public void surfaceDestroyed(SurfaceHolder holder)
+	{
+		Log.d("DolphinEmu", "Surface destroyed.");
+
+		if (mEmulationRunning)
+		{
+			pauseEmulation();
+		}
+	}
+
+	private void startEmulation()
+	{
+		if (!mEmulationStarted)
+		{
+			Log.d("DolphinEmu", "Starting emulation thread.");
+
+			mEmulationThread.start();
+		}
+		else
+		{
+			Log.d("DolphinEmu", "Resuming emulation.");
+			NativeLibrary.UnPauseEmulation();
+		}
+
+		mEmulationRunning = true;
+	}
+
+	private void pauseEmulation()
+	{
+		Log.d("DolphinEmu", "Pausing emulation.");
+
+		NativeLibrary.PauseEmulation();
+		mEmulationRunning = false;
+	}
+
+	private Runnable mEmulationRunner = new Runnable()
+	{
+		@Override
+		public void run()
+		{
+			mEmulationRunning = true;
+			mEmulationStarted = true;
+
+			// Loop until onSurfaceCreated succeeds
+			while (mSurface == null)
+			{
+				if (!mEmulationRunning)
+				{
+					// So that if the user quits before this gets a surface, we don't loop infinitely.
+					return;
+				}
+			}
+
+			Log.i("DolphinEmu", "Starting emulation: " + mSurface);
+
+			// Start emulation using the provided Surface.
+			NativeLibrary.Run(mSurface);
+		}
+	};
 }

Source/Android/app/src/main/res/layout/fragment_emulation.xml

@@ -5,7 +5,7 @@
              tools:context="org.dolphinemu.dolphinemu.fragments.EmulationFragment">
 
     <!-- This is what everything is rendered to during emulation -->
-    <org.dolphinemu.dolphinemu.emulation.NativeGLSurfaceView
+    <SurfaceView
         android:id="@+id/surface_emulation"
         android:layout_height="match_parent"
         android:layout_width="match_parent"

Source/Core/DolphinWX/MainAndroid.cpp

@@ -561,8 +561,16 @@ JNIEXPORT jstring JNICALL Java_org_dolphinemu_dolphinemu_NativeLibrary_GetUserDi
 
 JNIEXPORT void JNICALL Java_org_dolphinemu_dolphinemu_NativeLibrary_Run(JNIEnv *env, jobject obj, jobject _surf)
 {
+	__android_log_print(ANDROID_LOG_INFO, DOLPHIN_TAG, "Running : %s", g_filename.c_str());
+
 	surf = ANativeWindow_fromSurface(env, _surf);
 
+	if (surf == nullptr)
+	{
+		__android_log_print(ANDROID_LOG_ERROR, DOLPHIN_TAG, "Error: Surface is null.");
+		return;
+	}
+
 	// Install our callbacks
 	OSD::AddCallback(OSD::OSD_INIT, ButtonManager::Init);
 	OSD::AddCallback(OSD::OSD_SHUTDOWN, ButtonManager::Shutdown);
@@ -574,8 +582,11 @@ JNIEXPORT void JNICALL Java_org_dolphinemu_dolphinemu_NativeLibrary_Run(JNIEnv *
 
 	// No use running the loop when booting fails
 	if ( BootManager::BootCore( g_filename.c_str() ) )
+	{
+		PowerPC::Start();
 		while (PowerPC::GetState() != PowerPC::CPU_POWERDOWN)
 			updateMainFrameEvent.Wait();
+	}
 
 	UICommon::Shutdown();
 	ANativeWindow_release(surf);