widget/cocoa/ViewRegion.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef ViewRegion_h
   8 #define ViewRegion_h
   9
  10 #include "Units.h"
  11 #include "nsTArray.h"
  12
  13 class nsChildView;
  14
  15 @class NSView;
  16
  17 namespace mozilla {
  18
  19 /**
  20  * Manages a set of NSViews to cover a LayoutDeviceIntRegion.
  21  */
  22 class ViewRegion {
  23  public:
  24   ~ViewRegion();
  25
  26   mozilla::LayoutDeviceIntRegion Region() { return mRegion; }
  27
  28   /**
  29    * Update the region.
  30    * @param aRegion  The new region.
  31    * @param aCoordinateConverter  The nsChildView to use for converting
  32    *   LayoutDeviceIntRect device pixel coordinates into Cocoa NSRect
  33    * coordinates.
  34    * @param aContainerView  The view that's going to be the superview of the
  35    *   NSViews which will be created for this region.
  36    * @param aViewCreationCallback  A block that instantiates new NSViews.
  37    * @return  Whether or not the region changed.
  38    */
  39   bool UpdateRegion(const mozilla::LayoutDeviceIntRegion& aRegion,
  40                     const nsChildView& aCoordinateConverter,
  41                     NSView* aContainerView, NSView* (^aViewCreationCallback)());
  42
  43   /**
  44    * Return an NSView from the region, if there is any.
  45    */
  46   NSView* GetAnyView() { return mViews.Length() > 0 ? mViews[0] : NULL; }
  47
  48  private:
  49   mozilla::LayoutDeviceIntRegion mRegion;
  50   nsTArray<NSView*> mViews;
  51 };
  52
  53 }  // namespace mozilla
  54
  55 #endif  // ViewRegion_h