layout/base/nsFocusEventSuppressor.cpp

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   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
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   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
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  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
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  15  * The Original Code is mozilla.org code.
  16  *
  17  * The Initial Developer of the Original Code is Mozilla Foundation.
  18  * Portions created by the Initial Developer are Copyright (C) 2008
  19  * the Initial Developer. All Rights Reserved.
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  21  * Contributor(s):
  22  *   Olli Pettay <Olli.Pettay@helsinki.fi> (Original Author)
  23  *
  24  * Alternatively, the contents of this file may be used under the terms of
  25  * either of the GNU General Public License Version 2 or later (the "GPL"),
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  36  * ***** END LICENSE BLOCK ***** */
  37
  38 #include "nsIFocusEventSuppressor.h"
  39 #include "nsTArray.h"
  40
  41 class nsFocusEventSuppressorService : public nsIFocusEventSuppressorService
  42 {
  43 public:
  44   NS_DECL_ISUPPORTS
  45   virtual void AddObserverCallback(nsFocusEventSuppressorCallback aCallback)
  46   {
  47     NS_AddFocusSuppressorCallback(aCallback);
  48   }
  49   virtual void Suppress()
  50   {
  51     NS_SuppressFocusEvent();
  52   }
  53   virtual void Unsuppress()
  54   {
  55     NS_UnsuppressFocusEvent();
  56   }
  57 };
  58
  59 static nsTArray<nsFocusEventSuppressorCallback>* sCallbacks = nsnull;
  60 static PRUint32 sFocusSuppressCount = 0;
  61
  62 NS_IMPL_ADDREF(nsFocusEventSuppressorService)
  63 NS_IMPL_RELEASE(nsFocusEventSuppressorService)
  64
  65 NS_INTERFACE_MAP_BEGIN(nsFocusEventSuppressorService)
  66   NS_INTERFACE_MAP_ENTRY(nsIFocusEventSuppressorService)
  67   NS_INTERFACE_MAP_ENTRY(nsISupports)
  68 NS_INTERFACE_MAP_END
  69
  70 void
  71 NS_AddFocusSuppressorCallback(nsFocusEventSuppressorCallback aCallback)
  72 {
  73   if (aCallback) {
  74     if (!sCallbacks) {
  75       sCallbacks = new nsTArray<nsFocusEventSuppressorCallback>(2);
  76       if (!sCallbacks) {
  77         NS_WARNING("Out of memory!");
  78         return;
  79       }
  80     } else if (sCallbacks->Contains(aCallback)) {
  81       return;
  82     }
  83     sCallbacks->AppendElement(aCallback);
  84   }
  85 }
  86
  87 void
  88 NS_SuppressFocusEvent()
  89 {
  90   ++sFocusSuppressCount;
  91   if (sFocusSuppressCount == 1 && sCallbacks) {
  92     for (PRUint32 i = 0; i < sCallbacks->Length(); ++i) {
  93       sCallbacks->ElementAt(i)(PR_TRUE);
  94     }
  95   }
  96 }
  97
  98 void
  99 NS_UnsuppressFocusEvent()
 100 {
 101   --sFocusSuppressCount;
 102   if (sFocusSuppressCount == 0 && sCallbacks) {
 103     for (PRUint32 i = 0; i < sCallbacks->Length(); ++i) {
 104       sCallbacks->ElementAt(i)(PR_FALSE);
 105     }
 106   }
 107 }
 108
 109 void
 110 NS_ShutdownFocusSuppressor()
 111 {
 112   delete sCallbacks;
 113   sCallbacks = nsnull;
 114 }
 115
 116 nsresult
 117 NS_NewFocusEventSuppressorService(nsIFocusEventSuppressorService** aResult)
 118 {
 119   nsIFocusEventSuppressorService* it = new nsFocusEventSuppressorService();
 120   NS_ENSURE_TRUE(it, NS_ERROR_OUT_OF_MEMORY);
 121   NS_ADDREF(*aResult = it);
 122   return NS_OK;
 123 }