Behave properly when app is suspended

ports/libsimpleservo/src/api.rs

@@ -208,6 +208,12 @@ impl ServoGlue {
         self.process_event(event)
     }
 
+    /// Redraw the page.
+    pub fn refresh(&mut self) -> Result<(), &'static str> {
+        info!("refresh");
+        self.process_event(WindowEvent::Refresh)
+    }
+
     /// Stop loading the page.
     pub fn stop(&mut self) -> Result<(), &'static str> {
         debug!("TODO can't stop won't stop");

ports/libsimpleservo/src/capi.rs

@@ -144,6 +144,12 @@ pub extern "C" fn stop() {
     call(|s| s.stop());
 }
 
+#[no_mangle]
+pub extern "C" fn refresh() {
+    debug!("refresh");
+    call(|s| s.refresh());
+}
+
 #[no_mangle]
 pub extern "C" fn go_back() {
     debug!("go_back");

ports/libsimpleservo/src/jniapi.rs

@@ -145,6 +145,12 @@ pub fn Java_com_mozilla_servoview_JNIServo_stop(env: JNIEnv, _class: JClass) {
     call(env, |s| s.stop());
 }
 
+#[no_mangle]
+pub fn Java_com_mozilla_servoview_JNIServo_refresh(env: JNIEnv, _class: JClass) {
+    debug!("refresh");
+    call(env, |s| s.refresh());
+}
+
 #[no_mangle]
 pub fn Java_com_mozilla_servoview_JNIServo_goBack(env: JNIEnv, _class: JClass) {
     debug!("goBack");

support/android/apk/servoapp/src/main/java/com/mozilla/servo/MainActivity.java

@@ -151,4 +151,15 @@ public class MainActivity extends Activity implements Servo.Client {
         mFwdButton.setEnabled(canGoForward);
     }
 
+    @Override
+    public void onPause() {
+        mServoView.onPause();
+        super.onPause();
+    }
+    @Override
+    public void onResume() {
+        mServoView.onResume();
+        super.onResume();
+    }
+
 }

support/android/apk/servoview/src/main/java/com/mozilla/servoview/JNIServo.java

@@ -35,6 +35,8 @@ public class JNIServo {
 
     public native void stop();
 
+    public native void refresh();
+
     public native void goBack();
 
     public native void goForward();

support/android/apk/servoview/src/main/java/com/mozilla/servoview/Servo.java

@@ -17,6 +17,7 @@ public class Servo {
     private AssetManager mAssetMgr;
     private JNIServo mJNI = new JNIServo();
     private RunCallback mRunCallback;
+    private boolean mSuspended;
 
     public Servo(
             RunCallback runCallback,
@@ -49,6 +50,10 @@ public class Servo {
         mRunCallback.inGLThread(() -> mJNI.resize(width, height));
     }
 
+    public void refresh() {
+        mRunCallback.inGLThread(() -> mJNI.refresh());
+    }
+
     public void reload() {
         mRunCallback.inGLThread(() -> mJNI.reload());
     }
@@ -85,6 +90,10 @@ public class Servo {
         mRunCallback.inGLThread(() -> mJNI.click(x, y));
     }
 
+    public void suspend(boolean suspended) {
+        mSuspended = suspended;
+    }
+
     public interface Client {
         void onLoadStarted();
 
@@ -122,7 +131,9 @@ public class Servo {
         }
 
         public void wakeup() {
-            mRunCallback.inGLThread(() -> mJNI.performUpdates());
+            if (!mSuspended) {
+                mRunCallback.inGLThread(() -> mJNI.performUpdates());
+            }
         }
 
         public void flush() {

support/android/apk/servoview/src/main/java/com/mozilla/servoview/ServoView.java

@@ -54,6 +54,7 @@ public class ServoView extends GLSurfaceView
         setWillNotCacheDrawing(false);
         setEGLContextClientVersion(3);
         setEGLConfigChooser(8, 8, 8, 8, 24, 0);
+        setPreserveEGLContextOnPause(true);
         ServoGLRenderer mRenderer = new ServoGLRenderer(this);
         setRenderer(mRenderer);
         setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
@@ -80,9 +81,10 @@ public class ServoView extends GLSurfaceView
         mServo.stop();
     }
 
-    public void onSurfaceResized(int width, int height) {
+    public void onSurfaceInvalidated(int width, int height) {
         if (mServo != null) {
             mServo.resize(width, height);
+            mServo.refresh();
         }
     }
 
@@ -143,7 +145,7 @@ public class ServoView extends GLSurfaceView
 
         if (mScroller.isFinished() && mFlinging) {
             mFlinging = false;
-            queueEvent(() -> mServo.scrollEnd(0, 0, mCurX, mCurY));
+            inGLThread(() -> mServo.scrollEnd(0, 0, mCurX, mCurY));
             if (!mAnimating) {
                 // Not scrolling. Not animating. We don't need to schedule
                 // another frame.
@@ -164,7 +166,7 @@ public class ServoView extends GLSurfaceView
         mLastY = mCurY;
 
         if (dx != 0 || dy != 0) {
-            queueEvent(() -> mServo.scroll(dx, dy, mCurX, mCurY));
+            inGLThread(() -> mServo.scroll(dx, dy, mCurX, mCurY));
         } else {
             if (mAnimating) {
                 requestRender();
@@ -205,7 +207,7 @@ public class ServoView extends GLSurfaceView
                 mCurY = (int) e.getY();
                 mLastY = mCurY;
                 mScroller.forceFinished(true);
-                queueEvent(() -> mServo.scrollStart(0, 0, mCurX, mCurY));
+                inGLThread(() -> mServo.scrollStart(0, 0, mCurX, mCurY));
                 Choreographer.getInstance().postFrameCallback(this);
                 return true;
             case (MotionEvent.ACTION_MOVE):
@@ -215,7 +217,7 @@ public class ServoView extends GLSurfaceView
             case (MotionEvent.ACTION_UP):
             case (MotionEvent.ACTION_CANCEL):
                 if (!mFlinging) {
-                    queueEvent(() -> mServo.scrollEnd(0, 0, mCurX, mCurY));
+                    inGLThread(() -> mServo.scrollEnd(0, 0, mCurX, mCurY));
                     Choreographer.getInstance().removeFrameCallback(this);
                 }
                 return true;
@@ -225,7 +227,7 @@ public class ServoView extends GLSurfaceView
     }
 
     public boolean onSingleTapUp(MotionEvent e) {
-        queueEvent(() -> mServo.click((int) e.getX(), (int) e.getY()));
+        inGLThread(() -> mServo.click((int) e.getX(), (int) e.getY()));
         return false;
     }
 
@@ -239,6 +241,22 @@ public class ServoView extends GLSurfaceView
     public void onShowPress(MotionEvent e) {
     }
 
+    @Override
+    public void onPause() {
+      super.onPause();
+      if (mServo != null) {
+        mServo.suspend(true);
+      }
+    }
+
+    @Override
+    public void onResume() {
+      super.onResume();
+      if (mServo != null) {
+        mServo.suspend(false);
+      }
+    }
+
     static class ServoGLRenderer implements Renderer {
 
         private final ServoView mView;
@@ -254,9 +272,9 @@ public class ServoView extends GLSurfaceView
         public void onDrawFrame(GL10 unused) {
         }
 
-        public void onSurfaceChanged(GL10 unused, int width, int height) {
+        public void onSurfaceChanged(GL10 gl, int width, int height) {
             GLES31.glViewport(0, 0, width, height);
-            mView.onSurfaceResized(width, height);
+            mView.onSurfaceInvalidated(width, height);
         }
     }
 }