layout/forms/nsGfxCheckboxControlFrame.cpp

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  37
  38 #include "nsGfxCheckboxControlFrame.h"
  39 #include "nsIContent.h"
  40 #include "nsCOMPtr.h"
  41 #include "nsCSSRendering.h"
  42 #ifdef ACCESSIBILITY
  43 #include "nsAccessibilityService.h"
  44 #endif
  45 #include "nsIServiceManager.h"
  46 #include "nsIDOMHTMLInputElement.h"
  47 #include "nsDisplayList.h"
  48 #include "nsCSSAnonBoxes.h"
  49 #include "nsIDOMHTMLInputElement.h"
  50
  51 static void
  52 PaintCheckMark(nsIFrame* aFrame,
  53                nsIRenderingContext* aCtx,
  54                const nsRect& aDirtyRect,
  55                nsPoint aPt)
  56 {
  57   nsRect rect(aPt, aFrame->GetSize());
  58   rect.Deflate(aFrame->GetUsedBorderAndPadding());
  59
  60   // Points come from the coordinates on a 7X7 unit box centered at 0,0
  61   const PRInt32 checkPolygonX[] = { -3, -1,  3,  3, -1, -3 };
  62   const PRInt32 checkPolygonY[] = { -1,  1, -3, -1,  3,  1 };
  63   const PRInt32 checkNumPoints = sizeof(checkPolygonX) / sizeof(PRInt32);
  64   const PRInt32 checkSize      = 9; // 2 units of padding on either side
  65                                     // of the 7x7 unit checkmark
  66
  67   // Scale the checkmark based on the smallest dimension
  68   nscoord paintScale = NS_MIN(rect.width, rect.height) / checkSize;
  69   nsPoint paintCenter(rect.x + rect.width  / 2,
  70                       rect.y + rect.height / 2);
  71
  72   nsPoint paintPolygon[checkNumPoints];
  73   // Convert checkmark for screen rendering
  74   for (PRInt32 polyIndex = 0; polyIndex < checkNumPoints; polyIndex++) {
  75     paintPolygon[polyIndex] = paintCenter +
  76                               nsPoint(checkPolygonX[polyIndex] * paintScale,
  77                                       checkPolygonY[polyIndex] * paintScale);
  78   }
  79
  80   aCtx->SetColor(aFrame->GetStyleColor()->mColor);
  81   aCtx->FillPolygon(paintPolygon, checkNumPoints);
  82 }
  83
  84 static void
  85 PaintIndeterminateMark(nsIFrame* aFrame,
  86                        nsIRenderingContext* aCtx,
  87                        const nsRect& aDirtyRect,
  88                        nsPoint aPt)
  89 {
  90   nsRect rect(aPt, aFrame->GetSize());
  91   rect.Deflate(aFrame->GetUsedBorderAndPadding());
  92
  93   rect.y += (rect.height - rect.height/4) / 2;
  94   rect.height /= 4;
  95
  96   aCtx->SetColor(aFrame->GetStyleColor()->mColor);
  97   aCtx->FillRect(rect);
  98 }
  99
 100 //------------------------------------------------------------
 101 nsIFrame*
 102 NS_NewGfxCheckboxControlFrame(nsIPresShell* aPresShell,
 103                               nsStyleContext* aContext)
 104 {
 105   return new (aPresShell) nsGfxCheckboxControlFrame(aContext);
 106 }
 107
 108 NS_IMPL_FRAMEARENA_HELPERS(nsGfxCheckboxControlFrame)
 109
 110
 111 //------------------------------------------------------------
 112 // Initialize GFX-rendered state
 113 nsGfxCheckboxControlFrame::nsGfxCheckboxControlFrame(nsStyleContext* aContext)
 114 : nsFormControlFrame(aContext)
 115 {
 116 }
 117
 118 nsGfxCheckboxControlFrame::~nsGfxCheckboxControlFrame()
 119 {
 120 }
 121
 122 #ifdef ACCESSIBILITY
 123 already_AddRefed<nsAccessible>
 124 nsGfxCheckboxControlFrame::CreateAccessible()
 125 {
 126   nsAccessibilityService* accService = nsIPresShell::AccService();
 127   if (accService) {
 128     return accService->CreateHTMLCheckboxAccessible(mContent,
 129                                                     PresContext()->PresShell());
 130   }
 131
 132   return nsnull;
 133 }
 134 #endif
 135
 136 //------------------------------------------------------------
 137 NS_IMETHODIMP
 138 nsGfxCheckboxControlFrame::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
 139                                             const nsRect&           aDirtyRect,
 140                                             const nsDisplayListSet& aLists)
 141 {
 142   nsresult rv = nsFormControlFrame::BuildDisplayList(aBuilder, aDirtyRect,
 143                                                      aLists);
 144   NS_ENSURE_SUCCESS(rv, rv);
 145
 146   // Get current checked state through content model.
 147   if ((!IsChecked() && !IsIndeterminate()) || !IsVisibleForPainting(aBuilder))
 148     return NS_OK;   // we're not checked or not visible, nothing to paint.
 149
 150   if (IsThemed())
 151     return NS_OK; // No need to paint the checkmark. The theme will do it.
 152
 153   return aLists.Content()->AppendNewToTop(new (aBuilder)
 154     nsDisplayGeneric(aBuilder, this,
 155                      IsIndeterminate()
 156                      ? PaintIndeterminateMark : PaintCheckMark,
 157                      "CheckedCheckbox",
 158                      nsDisplayItem::TYPE_CHECKED_CHECKBOX));
 159 }
 160
 161 //------------------------------------------------------------
 162 PRBool
 163 nsGfxCheckboxControlFrame::IsChecked()
 164 {
 165   nsCOMPtr<nsIDOMHTMLInputElement> elem(do_QueryInterface(mContent));
 166   PRBool retval = PR_FALSE;
 167   elem->GetChecked(&retval);
 168   return retval;
 169 }
 170
 171 PRBool
 172 nsGfxCheckboxControlFrame::IsIndeterminate()
 173 {
 174   nsCOMPtr<nsIDOMHTMLInputElement> elem(do_QueryInterface(mContent));
 175   PRBool retval = PR_FALSE;
 176   elem->GetIndeterminate(&retval);
 177   return retval;
 178 }