layout/xul/nsXULLabelFrame.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 /* derived class of nsBlockFrame used for xul:label elements */
   7
   8 #include "mozilla/EventStateManager.h"
   9 #include "nsXULLabelFrame.h"
  10 #include "nsHTMLParts.h"
  11 #include "nsNameSpaceManager.h"
  12
  13 using namespace mozilla;
  14
  15 nsIFrame*
  16 NS_NewXULLabelFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
  17 {
  18   nsXULLabelFrame* it = new (aPresShell) nsXULLabelFrame(aContext);
  19
  20   it->SetFlags(NS_BLOCK_FLOAT_MGR | NS_BLOCK_MARGIN_ROOT);
  21
  22   return it;
  23 }
  24
  25 NS_IMPL_FRAMEARENA_HELPERS(nsXULLabelFrame)
  26
  27 // If you make changes to this function, check its counterparts
  28 // in nsBoxFrame and nsTextBoxFrame
  29 nsresult
  30 nsXULLabelFrame::RegUnregAccessKey(bool aDoReg)
  31 {
  32   // if we have no content, we can't do anything
  33   if (!mContent)
  34     return NS_ERROR_FAILURE;
  35
  36   // To filter out <label>s without a control attribute.
  37   // XXXjag a side-effect is that we filter out anonymous <label>s
  38   // in e.g. <menu>, <menuitem>, <button>. These <label>s inherit
  39   // |accesskey| and would otherwise register themselves, overwriting
  40   // the content we really meant to be registered.
  41   if (!mContent->HasAttr(kNameSpaceID_None, nsGkAtoms::control))
  42     return NS_OK;
  43
  44   nsAutoString accessKey;
  45   mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::accesskey, accessKey);
  46
  47   if (accessKey.IsEmpty())
  48     return NS_OK;
  49
  50   // With a valid PresContext we can get the ESM
  51   // and register the access key
  52   EventStateManager* esm = PresContext()->EventStateManager();
  53
  54   uint32_t key = accessKey.First();
  55   if (aDoReg)
  56     esm->RegisterAccessKey(mContent, key);
  57   else
  58     esm->UnregisterAccessKey(mContent, key);
  59
  60   return NS_OK;
  61 }
  62
  63 /////////////////////////////////////////////////////////////////////////////
  64 // nsIFrame
  65
  66 void
  67 nsXULLabelFrame::Init(nsIContent*       aContent,
  68                       nsContainerFrame* aParent,
  69                       nsIFrame*         aPrevInFlow)
  70 {
  71   nsBlockFrame::Init(aContent, aParent, aPrevInFlow);
  72
  73   // register access key
  74   RegUnregAccessKey(true);
  75 }
  76
  77 void
  78 nsXULLabelFrame::DestroyFrom(nsIFrame* aDestructRoot)
  79 {
  80   // unregister access key
  81   RegUnregAccessKey(false);
  82   nsBlockFrame::DestroyFrom(aDestructRoot);
  83 }
  84
  85 nsresult
  86 nsXULLabelFrame::AttributeChanged(int32_t aNameSpaceID,
  87                                   nsIAtom* aAttribute,
  88                                   int32_t aModType)
  89 {
  90   nsresult rv = nsBlockFrame::AttributeChanged(aNameSpaceID,
  91                                                aAttribute, aModType);
  92
  93   // If the accesskey changed, register for the new value
  94   // The old value has been unregistered in nsXULElement::SetAttr
  95   if (aAttribute == nsGkAtoms::accesskey || aAttribute == nsGkAtoms::control)
  96     RegUnregAccessKey(true);
  97
  98   return rv;
  99 }
 100
 101 nsIAtom*
 102 nsXULLabelFrame::GetType() const
 103 {
 104   return nsGkAtoms::XULLabelFrame;
 105 }
 106
 107 /////////////////////////////////////////////////////////////////////////////
 108 // Diagnostics
 109
 110 #ifdef DEBUG_FRAME_DUMP
 111 nsresult
 112 nsXULLabelFrame::GetFrameName(nsAString& aResult) const
 113 {
 114   return MakeFrameName(NS_LITERAL_STRING("XULLabel"), aResult);
 115 }
 116 #endif