Fixed bug with WebView onResume, improved Observable, fixed some other stuff

app/src/main/java/acr/browser/lightning/activity/BrowserActivity.java

@@ -186,6 +186,8 @@ public abstract class BrowserActivity extends ThemableBrowserActivity implements
     private String mUntitledTitle;
     private String mCameraPhotoPath;
 
+    private final Handler mDrawerHandler = new Handler();
+
     // The singleton BookmarkManager
     @Inject BookmarkManager mBookmarkManager;
 
@@ -923,7 +925,7 @@ public abstract class BrowserActivity extends ThemableBrowserActivity implements
         // Use a delayed handler to make the transition smooth
         // otherwise it will get caught up with the showTab code
         // and cause a janky motion
-        new Handler().postDelayed(new Runnable() {
+       mDrawerHandler.postDelayed(new Runnable() {
             @Override
             public void run() {
                 mDrawerLayout.closeDrawers();
@@ -959,14 +961,14 @@ public abstract class BrowserActivity extends ThemableBrowserActivity implements
         // Use a delayed handler to make the transition smooth
         // otherwise it will get caught up with the showTab code
         // and cause a janky motion
-        new Handler().postDelayed(new Runnable() {
+        mDrawerHandler.postDelayed(new Runnable() {
             @Override
             public void run() {
                 mDrawerLayout.closeDrawers();
             }
         }, 200);
 
-        // new Handler().postDelayed(new Runnable() {
+        // mDrawerHandler.postDelayed(new Runnable() {
         //     @Override
         //     public void run() {
         // Remove browser frame background to reduce overdraw
@@ -1168,16 +1170,12 @@ public abstract class BrowserActivity extends ThemableBrowserActivity implements
     @Override
     protected void onPause() {
         super.onPause();
-        final LightningView currentTab = mTabsManager.getCurrentTab();
         Log.d(TAG, "onPause");
-        if (currentTab != null) {
+        mTabsManager.pauseAll();
-            currentTab.pauseTimers();
-            currentTab.onPause();
-        }
         try {
             BrowserApp.get(this).unregisterReceiver(mNetworkReceiver);
         } catch (IllegalArgumentException e) {
-            e.printStackTrace();
+            Log.e(TAG, "Receiver was not registered", e);
         }
         if (isIncognito() && isFinishing()) {
             overridePendingTransition(R.anim.fade_in_scale, R.anim.slide_down_out);
@@ -1227,16 +1225,12 @@ public abstract class BrowserActivity extends ThemableBrowserActivity implements
     @Override
     protected void onResume() {
         super.onResume();
-        final LightningView currentTab = mTabsManager.getCurrentTab();
         Log.d(TAG, "onResume");
         if (mSuggestionsAdapter != null) {
             mSuggestionsAdapter.refreshPreferences();
             mSuggestionsAdapter.refreshBookmarks();
         }
-        if (currentTab != null) {
+        mTabsManager.resumeAll();
-            currentTab.resumeTimers();
-            currentTab.onResume();
-        }
         initializePreferences();
         mTabsManager.resume(this);
 
@@ -2157,8 +2151,7 @@ public abstract class BrowserActivity extends ThemableBrowserActivity implements
             mPresenter.loadUrlInCurrentView(event.url);
             // keep any jank from happening when the drawer is closed after the
             // URL starts to load
-            final Handler handler = new Handler();
+            mDrawerHandler.postDelayed(new Runnable() {
-            handler.postDelayed(new Runnable() {
                 @Override
                 public void run() {
                     mDrawerLayout.closeDrawer(mDrawerRight);

app/src/main/java/acr/browser/lightning/activity/TabsManager.java

@@ -190,6 +190,44 @@ public class TabsManager {
         });
     }
 
+    /**
+     * Method used to resume all the tabs in the browser.
+     * This is necessary because we cannot pause the
+     * WebView when the app is open currently due to a
+     * bug in the WebView, where calling onResume doesn't
+     * consistently resume it.
+     */
+    public void resumeAll() {
+        LightningView current = getCurrentTab();
+        if (current != null) {
+            current.resumeTimers();
+        }
+        for (LightningView tab : mTabList) {
+            if (tab != null) {
+                tab.onResume();
+            }
+        }
+    }
+
+    /**
+     * Method used to pause all the tabs in the browser.
+     * This is necessary because we cannot pause the
+     * WebView when the app is open currently due to a
+     * bug in the WebView, where calling onResume doesn't
+     * consistently resume it.
+     */
+    public void pauseAll() {
+        LightningView current = getCurrentTab();
+        if (current != null) {
+            current.pauseTimers();
+        }
+        for (LightningView tab : mTabList) {
+            if (tab != null) {
+                tab.onPause();
+            }
+        }
+    }
+
     /**
      * Return the tab at the given position in tabs list, or
      * null if position is not in tabs list range.

app/src/main/java/acr/browser/lightning/app/BrowserApp.java

@@ -2,7 +2,9 @@ package acr.browser.lightning.app;
 
 import android.app.Application;
 import android.content.Context;
+import android.os.Build;
 import android.support.annotation.NonNull;
+import android.webkit.WebView;
 
 import com.squareup.leakcanary.LeakCanary;
 import com.squareup.otto.Bus;
@@ -12,6 +14,8 @@ import java.util.concurrent.Executors;
 
 import javax.inject.Inject;
 
+import acr.browser.lightning.BuildConfig;
+
 public class BrowserApp extends Application {
 
     private static AppComponent mAppComponent;
@@ -26,6 +30,9 @@ public class BrowserApp extends Application {
         mAppComponent = DaggerAppComponent.builder().appModule(new AppModule(this)).build();
         mAppComponent.inject(this);
         LeakCanary.install(this);
+        if (BuildConfig.DEBUG && Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
+            WebView.setWebContentsDebuggingEnabled(true);
+        }
     }
 
     @NonNull

app/src/main/java/acr/browser/lightning/browser/BrowserPresenter.java

@@ -100,12 +100,16 @@ public class BrowserPresenter {
                 }
             } else {
                 if (mCurrentTab != null) {
-                    mCurrentTab.onPause();
+                    // TODO: Restore this when Google fixes the bug where the WebView is
+                    // blank after calling onPause followed by onResume.
+                    // mCurrentTab.onPause();
                     mCurrentTab.setForegroundTab(false);
                 }
-                newTab.onResume();
+
                 newTab.resumeTimers();
+                newTab.onResume();
                 newTab.setForegroundTab(true);
+
                 mView.updateProgress(newTab.getProgress());
                 mView.setBackButtonEnabled(newTab.canGoBack());
                 mView.setForwardButtonEnabled(newTab.canGoForward());
@@ -143,6 +147,7 @@ public class BrowserPresenter {
      *                 delete the tab.
      */
     public void deleteTab(int position) {
+        Log.d(TAG, "delete Tab");
         final LightningView tabToDelete = mTabsModel.getTabAtPosition(position);
 
         if (tabToDelete == null) {
@@ -280,6 +285,7 @@ public class BrowserPresenter {
      *                 tab to switch to.
      */
     public synchronized void tabChanged(int position) {
+        Log.d(TAG, "tabChanged: " + position);
         if (position < 0 || position >= mTabsModel.size()) {
             return;
         }

app/src/main/java/acr/browser/lightning/react/Observable.java

@@ -143,7 +143,7 @@ public class Observable<T> {
 
     private static class SubscriberImpl<T> implements Subscriber<T> {
 
-        @Nullable private OnSubscribe<T> mOnSubscribe;
+        @Nullable private volatile OnSubscribe<T> mOnSubscribe;
         @NonNull private final Observable<T> mObservable;
         private boolean mOnCompleteExecuted = false;
 
@@ -159,9 +159,10 @@ public class Observable<T> {
 
         @Override
         public void onComplete() {
-            if (!mOnCompleteExecuted && mOnSubscribe != null) {
+            OnSubscribe<T> onSubscribe = mOnSubscribe;
+            if (!mOnCompleteExecuted && onSubscribe != null) {
                 mOnCompleteExecuted = true;
-                mObservable.executeOnObserverThread(new OnCompleteRunnable<>(mOnSubscribe));
+                mObservable.executeOnObserverThread(new OnCompleteRunnable<>(onSubscribe));
             } else {
                 Log.e(TAG, "onComplete called more than once");
                 throw new RuntimeException("onComplete called more than once");
@@ -170,23 +171,26 @@ public class Observable<T> {
 
         @Override
         public void onStart() {
-            if (mOnSubscribe != null) {
+            OnSubscribe<T> onSubscribe = mOnSubscribe;
-                mObservable.executeOnObserverThread(new OnStartRunnable<>(mOnSubscribe));
+            if (onSubscribe != null) {
+                mObservable.executeOnObserverThread(new OnStartRunnable<>(onSubscribe));
             }
         }
 
         @Override
         public void onError(@NonNull final Throwable throwable) {
-            if (mOnSubscribe != null) {
+            OnSubscribe<T> onSubscribe = mOnSubscribe;
+            if (onSubscribe != null) {
                 mOnCompleteExecuted = true;
-                mObservable.executeOnObserverThread(new OnErrorRunnable<>(mOnSubscribe, throwable));
+                mObservable.executeOnObserverThread(new OnErrorRunnable<>(onSubscribe, throwable));
             }
         }
 
         @Override
         public void onNext(final T item) {
-            if (!mOnCompleteExecuted && mOnSubscribe != null) {
+            OnSubscribe<T> onSubscribe = mOnSubscribe;
-                mObservable.executeOnObserverThread(new OnNextRunnable<>(mOnSubscribe, item));
+            if (!mOnCompleteExecuted && onSubscribe != null) {
+                mObservable.executeOnObserverThread(new OnNextRunnable<>(onSubscribe, item));
             } else {
                 Log.e(TAG, "onComplete has been already called, onNext should not be called");
                 throw new RuntimeException("onNext should not be called after onComplete has been called");

app/src/main/java/acr/browser/lightning/view/LightningView.java

@@ -77,7 +77,7 @@ public class LightningView {
 
     private static String sHomepage;
     private static String sDefaultUserAgent;
-    private static float mMaxFling;
+    private static float sMaxFling;
     private static final float[] sNegativeColorArray = {
             -1.0f, 0, 0, 0, 255, // red
             0, -1.0f, 0, 0, 255, // green
@@ -116,10 +116,13 @@ public class LightningView {
         mActivity = activity;
         mUIController = (UIController) activity;
         mWebView = new WebView(activity);
+        if (Build.VERSION.SDK_INT > Build.VERSION_CODES.JELLY_BEAN) {
+            mWebView.setId(View.generateViewId());
+        }
         mIsIncognitoTab = isIncognito;
         mTitle = new LightningViewTitle(activity);
 
-        mMaxFling = ViewConfiguration.get(activity).getScaledMaximumFlingVelocity();
+        sMaxFling = ViewConfiguration.get(activity).getScaledMaximumFlingVelocity();
 
         mWebView.setDrawingCacheBackgroundColor(Color.WHITE);
         mWebView.setFocusableInTouchMode(true);
@@ -560,16 +563,20 @@ public class LightningView {
      * Pause the current WebView instance.
      */
     public synchronized void onPause() {
-        if (mWebView != null)
+        if (mWebView != null) {
             mWebView.onPause();
+            Log.d(TAG, "WebView onPause: " + mWebView.getId());
+        }
     }
 
     /**
      * Resume the current WebView instance.
      */
     public synchronized void onResume() {
-        if (mWebView != null)
+        if (mWebView != null) {
             mWebView.onResume();
+            Log.d(TAG, "WebView onResume: " + mWebView.getId());
+        }
     }
 
     /**
@@ -737,17 +744,19 @@ public class LightningView {
     public synchronized void pauseTimers() {
         if (mWebView != null) {
             mWebView.pauseTimers();
+            Log.d(TAG, "Pausing JS timers");
         }
     }
 
     /**
      * Resumes the JavaScript timers of the
-     * WebView instance, whihc will trigger a
+     * WebView instance, which will trigger a
      * resume for all WebViews in the app.
      */
     public synchronized void resumeTimers() {
         if (mWebView != null) {
             mWebView.resumeTimers();
+            Log.d(TAG, "Resuming JS timers");
         }
     }
 
@@ -1122,7 +1131,7 @@ public class LightningView {
 
         @Override
         public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
-            int power = (int) (velocityY * 100 / mMaxFling);
+            int power = (int) (velocityY * 100 / sMaxFling);
             if (power < -10) {
                 mUIController.hideActionBar();
             } else if (power > 15) {