Bug 513162 - Widget additions for recycling top level widgets as content containers. r=dbaron.

view/public/nsIView.h

@@ -63,8 +63,8 @@ enum nsViewVisibility {
 
 // IID for the nsIView interface
 #define NS_IVIEW_IID    \
-  { 0xe981334b, 0x756e, 0x417a, \
-    { 0xbf, 0x18, 0x47, 0x4a, 0x2d, 0xfe, 0xc3, 0x87 } }
+  { 0xdb512cfa, 0xe00c, 0x4eff, \
+    { 0xa2, 0x9c, 0x18, 0x74, 0x96, 0x63, 0x17, 0x69 } }
 
 // Public view flags are defined in this file
 #define NS_VIEW_FLAGS_PUBLIC              0x00FF
@@ -291,6 +291,26 @@ public:
                         nsContentType aWindowType = eContentTypeInherit,
                         nsIWidget* aParentWidget = nsnull);
 
+  /**
+   * Attach/detach a top level widget from this view. When attached, the view
+   * updates the widget's device context and allows the view to begin receiving
+   * gecko events. The underlying base window associated with the widget will
+   * continues to receive events it expects.
+   *
+   * An attached widget will not be destroyed when the view is destroyed,
+   * allowing the recycling of a single top level widget over multiple views.
+   *
+   * @param aWidget The widget to attach to / detach from.
+   */
+  nsresult AttachToTopLevelWidget(nsIWidget* aWidget);
+  nsresult DetachFromTopLevelWidget();
+
+  /**
+   * Returns a flag indicating whether the view owns it's widget
+   * or is attached to an existing top level widget.
+   */
+  PRBool IsAttachedToTopLevel() const { return mWidgetIsTopLevel; }
+
   /**
    * In 4.0, the "cutout" nature of a view is queryable.
    * If we believe that all cutout view have a native widget, this
@@ -373,6 +393,7 @@ protected:
   float             mOpacity;
   PRUint32          mVFlags;
   nsWeakView*       mDeletionObserver;
+  PRBool            mWidgetIsTopLevel;
 
   virtual ~nsIView() {}
 };

view/src/nsView.cpp

@@ -144,15 +144,47 @@ static ViewWrapper* GetWrapperFor(nsIWidget* aWidget)
   return nsnull;
 }
 
-//
 // Main events handler
-//
-nsEventStatus HandleEvent(nsGUIEvent *aEvent)
-{ 
-//printf(" %d %d %d (%d,%d) \n", aEvent->widget, aEvent->widgetSupports, 
-//       aEvent->message, aEvent->point.x, aEvent->point.y);
+static nsEventStatus HandleEvent(nsGUIEvent *aEvent)
+{
+#if 0
+  printf(" %d %d %d (%d,%d) \n", aEvent->widget, aEvent->widgetSupports, 
+         aEvent->message, aEvent->point.x, aEvent->point.y);
+#endif
   nsEventStatus result = nsEventStatus_eIgnore;
-  nsView       *view = nsView::GetViewFor(aEvent->widget);
+  nsView *view = nsView::GetViewFor(aEvent->widget);
+
+  if (view)
+  {
+    nsCOMPtr<nsIViewManager> vm = view->GetViewManager();
+    vm->DispatchEvent(aEvent, view, &result);
+  }
+
+  return result;
+}
+
+// Attached widget event helpers
+static ViewWrapper* GetAttachedWrapperFor(nsIWidget* aWidget)
+{
+  NS_PRECONDITION(nsnull != aWidget, "null widget ptr");
+  return aWidget->GetAttachedViewPtr();
+}
+
+static nsView* GetAttachedViewFor(nsIWidget* aWidget)
+{           
+  NS_PRECONDITION(nsnull != aWidget, "null widget ptr");
+
+  ViewWrapper* wrapper = GetAttachedWrapperFor(aWidget);
+  if (!wrapper)
+    return nsnull;
+  return wrapper->GetView();
+}
+
+// event handler
+static nsEventStatus AttachedHandleEvent(nsGUIEvent *aEvent)
+{ 
+  nsEventStatus result = nsEventStatus_eIgnore;
+  nsView *view = GetAttachedViewFor(aEvent->widget);
 
   if (view)
   {
@@ -176,6 +208,7 @@ nsView::nsView(nsViewManager* aViewManager, nsViewVisibility aVisibility)
   mViewManager = aViewManager;
   mDirtyRegion = nsnull;
   mDeletionObserver = nsnull;
+  mWidgetIsTopLevel = PR_FALSE;
 }
 
 void nsView::DropMouseGrabbing()
@@ -240,8 +273,21 @@ nsView::~nsView()
     ViewWrapper* wrapper = GetWrapperFor(mWindow);
     NS_IF_RELEASE(wrapper);
 
-    mWindow->SetClientData(nsnull);
-    mWindow->Destroy();
+    // If we are not attached to a base window, we're going to tear down our
+    // widget here. However, if we're attached to somebody elses widget, we
+    // want to leave the widget alone: don't reset the client data or call
+    // Destroy. Just clear our event view ptr and free our reference to it. 
+    if (mWidgetIsTopLevel) {
+      ViewWrapper* wrapper = GetAttachedWrapperFor(mWindow);
+      NS_IF_RELEASE(wrapper);
+
+      mWindow->SetAttachedViewPtr(nsnull);
+    }
+    else {
+      mWindow->SetClientData(nsnull);
+      mWindow->Destroy();
+    }
+
     NS_RELEASE(mWindow);
   }
   delete mDirtyRegion;
@@ -275,8 +321,13 @@ nsIView* nsIView::GetViewFor(nsIWidget* aWidget)
   NS_PRECONDITION(nsnull != aWidget, "null widget ptr");
 
   ViewWrapper* wrapper = GetWrapperFor(aWidget);
+
+  if (!wrapper)
+    wrapper = GetAttachedWrapperFor(aWidget);
+
   if (wrapper)
-    return wrapper->GetView();  
+    return wrapper->GetView();
+
   return nsnull;
 }
 
@@ -354,7 +405,7 @@ nsIntRect nsIView::CalcWidgetBounds(nsWindowType aType)
 
     if (parentWidget && aType == eWindowType_popup &&
         IsEffectivelyVisible()) {
-      // put offset into screen coordinates
+      // put offset into screen coordinates. (based on client area origin)
       nsIntPoint screenPoint = parentWidget->WidgetToScreenOffset();
       viewBounds += nsPoint(NSIntPixelsToAppUnits(screenPoint.x, p2a),
                             NSIntPixelsToAppUnits(screenPoint.y, p2a));
@@ -390,6 +441,7 @@ void nsView::DoResetWidgetBounds(PRBool aMoveOnly,
   
   nsIntRect curBounds;
   mWindow->GetBounds(curBounds);
+
   nsWindowType type;
   mWindow->GetWindowType(type);
 
@@ -409,6 +461,7 @@ void nsView::DoResetWidgetBounds(PRBool aMoveOnly,
   PRBool changedPos = curBounds.TopLeft() != newBounds.TopLeft();
   PRBool changedSize = curBounds.Size() != newBounds.Size();
 
+  // Child views are never attached to top level widgets, this is safe.
   if (changedPos) {
     if (changedSize && !aMoveOnly) {
       mWindow->Resize(newBounds.x, newBounds.y, newBounds.width, newBounds.height,
@@ -704,6 +757,62 @@ nsresult nsIView::CreateWidget(const nsIID &aWindowIID,
   return NS_OK;
 }
 
+// Attach to a top level widget and start receiving mirrored events.
+nsresult nsIView::AttachToTopLevelWidget(nsIWidget* aWidget)
+{
+  NS_PRECONDITION(nsnull != aWidget, "null widget ptr");
+  /// XXXjimm This is a temporary workaround to an issue w/document
+  // viewer (bug 513162).
+  nsIView *oldView = GetAttachedViewFor(aWidget);
+  if (oldView) {
+    oldView->DetachFromTopLevelWidget();
+  }
+
+  nsCOMPtr<nsIDeviceContext> dx;
+  mViewManager->GetDeviceContext(*getter_AddRefs(dx));
+
+  // Note, the previous device context will be released. Detaching
+  // will not restore the old one.
+  nsresult rv = aWidget->AttachViewToTopLevel(::AttachedHandleEvent, dx);
+  if (NS_FAILED(rv))
+    return rv;
+
+  mWindow = aWidget;
+  NS_ADDREF(mWindow);
+
+  nsView* v = static_cast<nsView*>(this);
+  ViewWrapper* wrapper = new ViewWrapper(v);
+  NS_ADDREF(wrapper);
+  mWindow->SetAttachedViewPtr(wrapper);
+  mWindow->EnableDragDrop(PR_TRUE);
+  mWidgetIsTopLevel = PR_TRUE;
+
+  // Refresh the view bounds
+  nsWindowType type;
+  mWindow->GetWindowType(type);
+  CalcWidgetBounds(type);
+
+  return NS_OK;
+}
+
+// Detach this view from an attached widget. 
+nsresult nsIView::DetachFromTopLevelWidget()
+{
+  NS_PRECONDITION(mWidgetIsTopLevel, "Not attached currently!");
+  NS_PRECONDITION(mWindow, "null mWindow for DetachFromTopLevelWidget!");
+
+  // Release memory for the view wrapper
+  ViewWrapper* wrapper = GetAttachedWrapperFor(mWindow);
+  NS_IF_RELEASE(wrapper);
+
+  mWindow->SetAttachedViewPtr(nsnull);
+  NS_RELEASE(mWindow);
+
+  mWidgetIsTopLevel = PR_FALSE;
+  
+  return NS_OK;
+}
+
 void nsView::SetZIndex(PRBool aAuto, PRInt32 aZIndex, PRBool aTopMost)
 {
   PRBool oldIsAuto = GetZIndexIsAuto();
@@ -834,6 +943,8 @@ nsIntPoint nsIView::GetScreenPosition() const
     PRInt32 p2a = dx->AppUnitsPerDevPixel();
     nsIntPoint ourPoint(NSAppUnitsToIntPixels(toWidgetOffset.x, p2a),
                         NSAppUnitsToIntPixels(toWidgetOffset.y, p2a));
+    // WidgetToScreenOffset is at the origin of the client area of
+    // the widget.
     screenPoint = ourPoint + widget->WidgetToScreenOffset();
   }
   
@@ -842,6 +953,9 @@ nsIntPoint nsIView::GetScreenPosition() const
 
 nsIWidget* nsIView::GetNearestWidget(nsPoint* aOffset) const
 {
+  // aOffset is based on the view's position, which ignores any chrome on
+  // attached parent widgets.
+
   nsPoint pt(0, 0);
   const nsView* v;
   for (v = static_cast<const nsView*>(this);
@@ -855,9 +969,9 @@ nsIWidget* nsIView::GetNearestWidget(nsPoint* aOffset) const
     return nsnull;
   }
 
-  // pt is now the offset from v's origin to this's origin
-  // The widget's origin is the top left corner of v's bounds, which may
-  // not coincide with v's origin
+  // pt is now the offset from v's origin to this view's origin. The widget's
+  // origin is the top left corner of v's bounds, which may not coincide with
+  // the view's origin.
   if (aOffset) {
     nsRect vBounds = v->GetBounds();
     *aOffset = pt + v->GetPosition() -  nsPoint(vBounds.x, vBounds.y) +

view/src/nsViewManager.cpp

@@ -304,6 +304,20 @@ NS_IMETHODIMP nsViewManager::GetWindowDimensions(nscoord *aWidth, nscoord *aHeig
   return NS_OK;
 }
 
+void nsViewManager::DoSetWindowDimensions(nscoord aWidth, nscoord aHeight)
+{
+  nsRect oldDim;
+  nsRect newDim(0, 0, aWidth, aHeight);
+  mRootView->GetDimensions(oldDim);
+  // We care about resizes even when one dimension is already zero.
+  if (!oldDim.IsExactEqual(newDim)) {
+    // Don't resize the widget. It is already being set elsewhere.
+    mRootView->SetDimensions(newDim, PR_TRUE, PR_FALSE);
+    if (mObserver)
+      mObserver->ResizeReflow(mRootView, aWidth, aHeight);
+  }
+}
+
 NS_IMETHODIMP nsViewManager::SetWindowDimensions(nscoord aWidth, nscoord aHeight)
 {
   if (mRootView) {
@@ -578,6 +592,13 @@ nsViewManager::UpdateWidgetArea(nsView *aWidgetView, nsIWidget* aWidget,
                                 const nsRegion &aDamagedRegion,
                                 nsView* aIgnoreWidgetView)
 {
+#if 0
+  nsRect dbgBounds = aDamagedRegion.GetBounds();
+  printf("UpdateWidgetArea view:%X (%d) widget:%X region: %d, %d, %d, %d\n",
+    aWidgetView, aWidgetView->IsAttachedToTopLevel(),
+    aWidget, dbgBounds.x, dbgBounds.y, dbgBounds.width, dbgBounds.height);
+#endif
+
   if (!IsRefreshEnabled()) {
     // accumulate this rectangle in the view's dirty region, so we can
     // process it later.
@@ -639,14 +660,19 @@ nsViewManager::UpdateWidgetArea(nsView *aWidgetView, nsIWidget* aWidget,
         // Don't mess with views that are in completely different view
         // manager trees
         if (view->GetViewManager()->RootViewManager() == RootViewManager()) {
-          // get the damage region into 'view's coordinate system
+          // get the damage region into view's coordinate system
           nsRegion damage = intersection;
+
           nsPoint offset = view->GetOffsetTo(aWidgetView);
           damage.MoveBy(-offset);
+
+          // Update the child and it's children
           UpdateWidgetArea(view, childWidget, damage, aIgnoreWidgetView);
 
+          // GetBounds should compensate for chrome on a toplevel widget
           nsIntRect bounds;
           childWidget->GetBounds(bounds);
+
           nsTArray<nsIntRect> clipRects;
           childWidget->GetWindowClipRegion(&clipRects);
           for (PRUint32 i = 0; i < clipRects.Length(); ++i) {
@@ -741,10 +767,9 @@ NS_IMETHODIMP nsViewManager::DispatchEvent(nsGUIEvent *aEvent,
       {
         if (aView)
           {
+            // client area dimensions are set on the view
             nscoord width = ((nsSizeEvent*)aEvent)->windowSize->width;
             nscoord height = ((nsSizeEvent*)aEvent)->windowSize->height;
-            width = ((nsSizeEvent*)aEvent)->mWinWidth;
-            height = ((nsSizeEvent*)aEvent)->mWinHeight;
 
             // The root view may not be set if this is the resize associated with
             // window creation
@@ -1011,9 +1036,10 @@ NS_IMETHODIMP nsViewManager::DispatchEvent(nsGUIEvent *aEvent,
 
 nsEventStatus nsViewManager::HandleEvent(nsView* aView, nsGUIEvent* aEvent)
 {
-//printf(" %d %d %d %d (%d,%d) \n", this, event->widget, event->widgetSupports, 
-//       event->message, event->point.x, event->point.y);
-
+#if 0
+  printf(" %d %d %d %d (%d,%d) \n", this, event->widget, event->widgetSupports, 
+         event->message, event->point.x, event->point.y);
+#endif
   // Hold a refcount to the observer. The continued existence of the observer will
   // delay deletion of this view hierarchy should the event want to cause its
   // destruction in, say, some JavaScript event handler.

view/src/nsViewManager.h

@@ -209,19 +209,7 @@ private:
    */
   nsIntRect ViewToWidget(nsView *aView, nsView* aWidgetView, const nsRect &aRect) const;
 
-  void DoSetWindowDimensions(nscoord aWidth, nscoord aHeight)
-  {
-    nsRect oldDim;
-    nsRect newDim(0, 0, aWidth, aHeight);
-    mRootView->GetDimensions(oldDim);
-    // We care about resizes even when one dimension is already zero.
-    if (!oldDim.IsExactEqual(newDim)) {
-      // Don't resize the widget. It is already being set elsewhere.
-      mRootView->SetDimensions(newDim, PR_TRUE, PR_FALSE);
-      if (mObserver)
-        mObserver->ResizeReflow(mRootView, aWidth, aHeight);
-    }
-  }
+  void DoSetWindowDimensions(nscoord aWidth, nscoord aHeight);
 
   // Safety helpers
   void IncrementUpdateCount() {