Fix for Android kiosk mode components

modules/juce_gui_basics/native/juce_android_Windowing.cpp

@@ -106,13 +106,15 @@ DECLARE_JNI_CLASS (CanvasMinimal, "android/graphics/Canvas");
  METHOD (invalidate,    "invalidate",       "(IIII)V") \
  METHOD (containsPoint, "containsPoint",    "(II)Z") \
  METHOD (showKeyboard,  "showKeyboard",     "(Ljava/lang/String;)V") \
+ METHOD (setSystemUiVisibility, "setSystemUiVisibility", "(I)V") \
 
 DECLARE_JNI_CLASS (ComponentPeerView, JUCE_ANDROID_ACTIVITY_CLASSPATH "$ComponentPeerView");
 #undef JNI_CLASS_MEMBERS
 
 
 //==============================================================================
-class AndroidComponentPeer  : public ComponentPeer
+class AndroidComponentPeer  : public ComponentPeer,
+                              private Timer
 {
 public:
     AndroidComponentPeer (Component& comp, const int windowStyleFlags)
@@ -183,7 +185,6 @@ public:
                     view.callVoidMethod (ComponentPeerView.setVisible, shouldBeVisible);
                 }
 
-            private:
                 GlobalRef view;
                 bool shouldBeVisible;
             };
@@ -237,7 +238,7 @@ public:
                                view.callIntMethod (ComponentPeerView.getHeight)) / scale;
     }
 
-    void handleScreenSizeChange()
+    void handleScreenSizeChange() override
     {
         ComponentPeer::handleScreenSizeChange();
 
@@ -271,8 +272,46 @@ public:
         return false;
     }
 
+    bool shouldNavBarsBeHidden() const
+    {
+        if (fullScreen)
+            if (Component* kiosk = Desktop::getInstance().getKioskModeComponent())
+                if (kiosk->getPeer() == this)
+                    return true;
+
+        return false;
+    }
+
+    void setNavBarsHidden (bool hidden) const
+    {
+        enum
+        {
+            SYSTEM_UI_FLAG_VISIBLE                  = 0,
+            SYSTEM_UI_FLAG_LOW_PROFILE              = 1,
+            SYSTEM_UI_FLAG_HIDE_NAVIGATION          = 2,
+            SYSTEM_UI_FLAG_FULLSCREEN               = 4,
+            SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION   = 512,
+            SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN        = 1024,
+            SYSTEM_UI_FLAG_IMMERSIVE                = 2048,
+            SYSTEM_UI_FLAG_IMMERSIVE_STICKY         = 4096
+        };
+
+        view.callVoidMethod (ComponentPeerView.setSystemUiVisibility,
+                             hidden ? (jint) (SYSTEM_UI_FLAG_HIDE_NAVIGATION | SYSTEM_UI_FLAG_FULLSCREEN | SYSTEM_UI_FLAG_IMMERSIVE_STICKY)
+                                    : (jint) (SYSTEM_UI_FLAG_VISIBLE));
+    }
+
     void setFullScreen (bool shouldBeFullScreen) override
     {
+        // updating the nav bar visibility is a bit odd on Android - need to wait for
+        if (shouldNavBarsBeHidden())
+        {
+            if (! isTimerRunning())
+                startTimer (500);
+        }
+        else
+            setNavBarsHidden (false);
+
         Rectangle<int> r (shouldBeFullScreen ? Desktop::getInstance().getDisplays().getMainDisplay().userArea
                                              : lastNonFullscreenBounds);
 
@@ -291,6 +330,13 @@ public:
         return fullScreen;
     }
 
+    void timerCallback() override
+    {
+        setNavBarsHidden (shouldNavBarsBeHidden());
+        setFullScreen (fullScreen);
+        stopTimer();
+    }
+
     void setIcon (const Image& newIcon) override
     {
         // n/a
@@ -327,7 +373,7 @@ public:
         handleBroughtToFront();
     }
 
-    void toBehind (ComponentPeer* other) override
+    void toBehind (ComponentPeer*) override
     {
         // TODO
     }
@@ -723,9 +769,14 @@ bool Desktop::isScreenSaverEnabled()
 }
 
 //==============================================================================
-void Desktop::setKioskComponent (Component* kioskModeComponent, bool enableOrDisable, bool allowMenusAndBars)
+void Desktop::setKioskComponent (Component* kioskComp, bool enableOrDisable, bool allowMenusAndBars)
 {
-    // TODO
+    ignoreUnused (allowMenusAndBars);
+
+    if (AndroidComponentPeer* peer = dynamic_cast<AndroidComponentPeer*> (kioskComp->getPeer()))
+        peer->setFullScreen (enableOrDisable);
+    else
+        jassertfalse; // (this should have been checked by the caller)
 }
 
 //==============================================================================