Android: Improve the foreign-window implementation

Adds:
- Improved geometry calculations (e.g, inside a parent)
- Change visibility
- proper stacking order. Native views now reserve the top of the stack
  to ensure that they stay visible.
- React to application state changes.

Change-Id: I35de0396937fff37ffcd272c9a7d8e9873a91dfb
Reviewed-by: Paul Olav Tvete <paul.tvete@digia.com>

src/android/jar/src/org/qtproject/qt5/android/QtActivityDelegate.java

@@ -1025,8 +1025,8 @@ public class QtActivityDelegate
             view.setLayoutParams(new QtLayout.LayoutParams(w, h, x, y));
         }
 
+        view.setId(id);
         m_layout.addView(view);
-        m_layout.bringChildToFront(view);
         m_nativeViews.put(id, view);
     }
 
@@ -1057,9 +1057,11 @@ public class QtActivityDelegate
             surface.setLayoutParams( new QtLayout.LayoutParams(w, h, x, y));
         }
 
-        m_layout.addView(surface);
+        // Native views are always inserted in the end of the stack (i.e., on top).
-        if (onTop)
+        // All other views are stacked based on the order they are created.
-            m_layout.bringChildToFront(surface);
+        final int index = m_layout.getChildCount() - m_nativeViews.size() - 1;
+        m_layout.addView(surface, index < 0 ? 0 : index);
+
         m_surfaces.put(id, surface);
     }
 
@@ -1070,7 +1072,6 @@ public class QtActivityDelegate
         } else if (m_nativeViews.containsKey(id)) {
             View view = m_nativeViews.get(id);
             view.setLayoutParams(new QtLayout.LayoutParams(w, h, x, y));
-            m_layout.bringChildToFront(view);
         } else {
             Log.e(QtNative.QtTAG, "Surface " + id +" not found!");
             return;

src/plugins/platforms/android/androidjnimain.cpp

@@ -69,7 +69,6 @@ static AAssetManager *m_assetManager = Q_NULLPTR;
 static jobject m_resourcesObj = Q_NULLPTR;
 static jobject m_activityObject = Q_NULLPTR;
 static jmethodID m_createSurfaceMethodID = Q_NULLPTR;
-static jmethodID m_insertNativeViewMethodID = Q_NULLPTR;
 static jmethodID m_setSurfaceGeometryMethodID = Q_NULLPTR;
 static jmethodID m_destroySurfaceMethodID = Q_NULLPTR;
 
@@ -345,27 +344,24 @@ namespace QtAndroid
 
     int insertNativeView(jobject view, const QRect &geometry)
     {
-        QJNIEnvironmentPrivate env;
-        if (!env)
-            return 0;
-
         m_surfacesMutex.lock();
         const int surfaceId = m_surfaceId++;
+        m_surfaces[surfaceId] = Q_NULLPTR; // dummy
         m_surfacesMutex.unlock();
 
         jint x = 0, y = 0, w = -1, h = -1;
-        if (!geometry.isNull()) {
+        if (!geometry.isNull())
-            x = geometry.x();
+            geometry.getRect(&x, &y, &w, &h);
-            y = geometry.y();
-            w = std::max(geometry.width(), 1);
-            h = std::max(geometry.height(), 1);
-        }
 
-        env->CallStaticVoidMethod(m_applicationClass,
+        QJNIObjectPrivate::callStaticMethod<void>(m_applicationClass,
-                                  m_insertNativeViewMethodID,
+                                                  "insertNativeView",
+                                                  "(ILandroid/view/View;IIII)V",
                                                   surfaceId,
                                                   view,
-                                  x, y, w, h);
+                                                  x,
+                                                  y,
+                                                  qMax(w, 1),
+                                                  qMax(h, 1));
 
         return surfaceId;
     }
@@ -539,6 +535,9 @@ static void setSurface(JNIEnv *env, jobject /*thiz*/, jint id, jobject jSurface,
 {
     QMutexLocker lock(&m_surfacesMutex);
     const auto &it = m_surfaces.find(id);
+    if (it.value() == Q_NULLPTR) // This should never happen...
+        return;
+
     if (it == m_surfaces.end()) {
         qWarning()<<"Can't find surface" << id;
         return;
@@ -718,7 +717,6 @@ static int registerNatives(JNIEnv *env)
     }
 
     GET_AND_CHECK_STATIC_METHOD(m_createSurfaceMethodID, m_applicationClass, "createSurface", "(IZIIIII)V");
-    GET_AND_CHECK_STATIC_METHOD(m_insertNativeViewMethodID, m_applicationClass, "insertNativeView", "(ILandroid/view/View;IIII)V");
     GET_AND_CHECK_STATIC_METHOD(m_setSurfaceGeometryMethodID, m_applicationClass, "setSurfaceGeometry", "(IIIII)V");
     GET_AND_CHECK_STATIC_METHOD(m_destroySurfaceMethodID, m_applicationClass, "destroySurface", "(I)V");
 

src/plugins/platforms/android/qandroidplatformforeignwindow.cpp

@@ -34,16 +34,17 @@
 #include "qandroidplatformforeignwindow.h"
 #include "androidjnimain.h"
 #include <QtCore/qvariant.h>
+#include <qpa/qwindowsysteminterface.h>
+#include <QtCore/private/qjnihelpers_p.h>
+
+QT_BEGIN_NAMESPACE
 
 QAndroidPlatformForeignWindow::QAndroidPlatformForeignWindow(QWindow *window)
-    : QAndroidPlatformWindow(window)
+    : QAndroidPlatformWindow(window),
+      m_surfaceId(-1)
 {
     const WId wId = window->property("_q_foreignWinId").value<WId>();
-    if (wId) {
     m_view = reinterpret_cast<jobject>(wId);
-        Q_ASSERT(m_view.isValid());
-        m_surfaceId = QtAndroid::insertNativeView(m_view.object(), geometry());
-    }
 }
 
 QAndroidPlatformForeignWindow::~QAndroidPlatformForeignWindow()
@@ -54,9 +55,64 @@ QAndroidPlatformForeignWindow::~QAndroidPlatformForeignWindow()
 
 void QAndroidPlatformForeignWindow::setGeometry(const QRect &rect)
 {
-    if (rect == geometry())
+    QWindow *parent = window()->parent();
+    QRect newGeometry = rect;
+
+    if (parent != 0)
+        newGeometry.moveTo(parent->mapToGlobal(rect.topLeft()));
+
+    if (newGeometry == geometry())
         return;
 
-    QAndroidPlatformWindow::setGeometry(rect);
+    QAndroidPlatformWindow::setGeometry(newGeometry);
-    QtAndroid::setSurfaceGeometry(m_surfaceId, rect);
+
+    if (m_surfaceId != -1)
+        QtAndroid::setSurfaceGeometry(m_surfaceId, newGeometry);
 }
+
+void QAndroidPlatformForeignWindow::setVisible(bool visible)
+{
+    if (!m_view.isValid())
+        return;
+
+    QAndroidPlatformWindow::setVisible(visible);
+
+    if (!visible && m_surfaceId != -1) {
+        QtAndroid::destroySurface(m_surfaceId);
+        m_surfaceId = -1;
+    } else if (m_surfaceId == -1) {
+        m_surfaceId = QtAndroid::insertNativeView(m_view.object(), geometry());
+    }
+}
+
+void QAndroidPlatformForeignWindow::applicationStateChanged(Qt::ApplicationState state)
+{
+    if (state <= Qt::ApplicationHidden
+            && QtAndroid::blockEventLoopsWhenSuspended()
+            && m_surfaceId != -1) {
+        QtAndroid::destroySurface(m_surfaceId);
+        m_surfaceId = -1;
+    } else if (m_view.isValid() && m_surfaceId == -1){
+        m_surfaceId = QtAndroid::insertNativeView(m_view.object(), geometry());
+    }
+
+    QAndroidPlatformWindow::applicationStateChanged(state);
+}
+
+void QAndroidPlatformForeignWindow::setParent(const QPlatformWindow *window)
+{
+    QRect newGeometry = geometry();
+
+    if (window != 0)
+        newGeometry.moveTo(window->mapToGlobal(geometry().topLeft()));
+
+    if (newGeometry != geometry())
+        QAndroidPlatformWindow::setGeometry(newGeometry);
+
+    if (m_surfaceId == -1)
+        return;
+
+    QtAndroid::setSurfaceGeometry(m_surfaceId, newGeometry);
+}
+
+QT_END_NAMESPACE

src/plugins/platforms/android/qandroidplatformforeignwindow.h

@@ -38,16 +38,23 @@
 #include "qandroidplatformwindow.h"
 #include <QtCore/private/qjni_p.h>
 
+QT_BEGIN_NAMESPACE
+
 class QAndroidPlatformForeignWindow : public QAndroidPlatformWindow
 {
 public:
     explicit QAndroidPlatformForeignWindow(QWindow *window);
     ~QAndroidPlatformForeignWindow();
-    void setGeometry(const QRect &rect);
+    void setGeometry(const QRect &rect) Q_DECL_OVERRIDE;
+    void setVisible(bool visible) Q_DECL_OVERRIDE;
+    void applicationStateChanged(Qt::ApplicationState state) Q_DECL_OVERRIDE;
+    void setParent(const QPlatformWindow *window) Q_DECL_OVERRIDE;
 
 private:
+    int m_surfaceId;
     QJNIObjectPrivate m_view;
-    int m_surfaceId = -1;
 };
 
+QT_END_NAMESPACE
+
 #endif // QANDROIDPLATFORMFOREIGNWINDOW_H

src/plugins/platforms/android/qandroidplatformwindow.h

@@ -65,6 +65,9 @@ public:
     void requestActivateWindow();
     void updateStatusBarVisibility();
     inline bool isRaster() const {
+        if ((window()->flags() & Qt::ForeignWindow) == Qt::ForeignWindow)
+            return false;
+
         return window()->surfaceType() == QSurface::RasterSurface
             || window()->surfaceType() == QSurface::RasterGLSurface;
     }