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 "nsRegion.h"
  12 #include "nsTArray.h"
  13
  14 class nsChildView;
  15
  16 @class NSView;
  17
  18 namespace mozilla {
  19
  20 /**
  21  * Manages a set of NSViews to cover a LayoutDeviceIntRegion.
  22  */
  23 class ViewRegion {
  24  public:
  25   ~ViewRegion();
  26
  27   mozilla::LayoutDeviceIntRegion Region() { return mRegion; }
  28
  29   /**
  30    * Update the region.
  31    * @param aRegion  The new region.
  32    * @param aCoordinateConverter  The nsChildView to use for converting
  33    *   LayoutDeviceIntRect device pixel coordinates into Cocoa NSRect
  34    * coordinates.
  35    * @param aContainerView  The view that's going to be the superview of the
  36    *   NSViews which will be created for this region.
  37    * @param aViewCreationCallback  A block that instantiates new NSViews.
  38    * @return  Whether or not the region changed.
  39    */
  40   bool UpdateRegion(const mozilla::LayoutDeviceIntRegion& aRegion,
  41                     const nsChildView& aCoordinateConverter,
  42                     NSView* aContainerView, NSView* (^aViewCreationCallback)());
  43
  44   /**
  45    * Return an NSView from the region, if there is any.
  46    */
  47   NSView* GetAnyView() { return mViews.Length() > 0 ? mViews[0] : NULL; }
  48
  49  private:
  50   mozilla::LayoutDeviceIntRegion mRegion;
  51   nsTArray<NSView*> mViews;
  52 };
  53
  54 }  // namespace mozilla
  55
  56 #endif  // ViewRegion_h