layout/generic/nsAreaFrame.cpp

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  37
  38 /* derived class of nsBlockFrame; distinction barely relevant anymore */
  39
  40 #include "nsAreaFrame.h"
  41 #include "nsBlockBandData.h"
  42 #include "nsStyleContext.h"
  43 #include "nsStyleConsts.h"
  44 #include "nsPresContext.h"
  45 #include "nsINodeInfo.h"
  46 #include "nsGkAtoms.h"
  47 #include "nsHTMLParts.h"
  48
  49 #ifdef MOZ_XUL
  50 #include "nsINameSpaceManager.h"
  51 #include "nsIEventStateManager.h"
  52 #endif
  53
  54 #undef NOISY_MAX_ELEMENT_SIZE
  55 #undef NOISY_FINAL_SIZE
  56
  57 nsIFrame*
  58 NS_NewAreaFrame(nsIPresShell* aPresShell, nsStyleContext* aContext, PRUint32 aFlags)
  59 {
  60   nsAreaFrame* it = new (aPresShell) nsAreaFrame(aContext);
  61
  62   if (it != nsnull)
  63     it->SetFlags(aFlags);
  64
  65   return it;
  66 }
  67
  68 #ifdef MOZ_XUL
  69
  70 // If you make changes to this function, check its counterparts
  71 // in nsBoxFrame and nsTextBoxFrame
  72 nsresult
  73 nsAreaFrame::RegUnregAccessKey(PRBool aDoReg)
  74 {
  75   // if we have no content, we can't do anything
  76   if (!mContent)
  77     return NS_ERROR_FAILURE;
  78
  79   // only support accesskeys for the following elements
  80   if (!mContent->NodeInfo()->Equals(nsGkAtoms::label, kNameSpaceID_XUL))
  81     return NS_OK;
  82
  83   // To filter out <label>s without a control attribute.
  84   // XXXjag a side-effect is that we filter out anonymous <label>s
  85   // in e.g. <menu>, <menuitem>, <button>. These <label>s inherit
  86   // |accesskey| and would otherwise register themselves, overwriting
  87   // the content we really meant to be registered.
  88   if (!mContent->HasAttr(kNameSpaceID_None, nsGkAtoms::control))
  89     return NS_OK;
  90
  91   nsAutoString accessKey;
  92   mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::accesskey, accessKey);
  93
  94   if (accessKey.IsEmpty())
  95     return NS_OK;
  96
  97   // With a valid PresContext we can get the ESM
  98   // and register the access key
  99   nsIEventStateManager *esm = PresContext()->EventStateManager();
 100   nsresult rv;
 101
 102   PRUint32 key = accessKey.First();
 103   if (aDoReg)
 104     rv = esm->RegisterAccessKey(mContent, key);
 105   else
 106     rv = esm->UnregisterAccessKey(mContent, key);
 107
 108   return rv;
 109 }
 110 #endif
 111
 112 /////////////////////////////////////////////////////////////////////////////
 113 // nsIFrame
 114
 115 #ifdef MOZ_XUL
 116 NS_IMETHODIMP
 117 nsAreaFrame::Init(nsIContent*      aContent,
 118                   nsIFrame*        aParent,
 119                   nsIFrame*        aPrevInFlow)
 120 {
 121   nsresult rv = nsBlockFrame::Init(aContent, aParent, aPrevInFlow);
 122   if (NS_FAILED(rv))
 123     return rv;
 124
 125   // register access key
 126   return RegUnregAccessKey(PR_TRUE);
 127 }
 128
 129 void
 130 nsAreaFrame::Destroy()
 131 {
 132   // unregister access key
 133   RegUnregAccessKey(PR_FALSE);
 134   nsBlockFrame::Destroy();
 135 }
 136
 137 NS_IMETHODIMP
 138 nsAreaFrame::AttributeChanged(PRInt32 aNameSpaceID,
 139                               nsIAtom* aAttribute,
 140                               PRInt32 aModType)
 141 {
 142   nsresult rv = nsBlockFrame::AttributeChanged(aNameSpaceID,
 143                                                aAttribute, aModType);
 144
 145   // If the accesskey changed, register for the new value
 146   // The old value has been unregistered in nsXULElement::SetAttr
 147   if (aAttribute == nsGkAtoms::accesskey || aAttribute == nsGkAtoms::control)
 148     RegUnregAccessKey(PR_TRUE);
 149
 150   return rv;
 151 }
 152 #endif
 153
 154 nsIAtom*
 155 nsAreaFrame::GetType() const
 156 {
 157   return nsGkAtoms::areaFrame;
 158 }
 159
 160 /////////////////////////////////////////////////////////////////////////////
 161 // Diagnostics
 162
 163 #ifdef NS_DEBUG
 164 NS_IMETHODIMP
 165 nsAreaFrame::GetFrameName(nsAString& aResult) const
 166 {
 167   return MakeFrameName(NS_LITERAL_STRING("Area"), aResult);
 168 }
 169 #endif