widget/windows/nsColorPicker.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
   2  *
   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 #include "nsColorPicker.h"
   8
   9 #include <shlwapi.h>
  10
  11 #include "mozilla/AutoRestore.h"
  12 #include "nsIWidget.h"
  13 #include "nsString.h"
  14 #include "WidgetUtils.h"
  15
  16 using namespace mozilla::widget;
  17
  18 namespace
  19 {
  20 // Manages NS_NATIVE_TMP_WINDOW child windows. NS_NATIVE_TMP_WINDOWs are
  21 // temporary child windows of mParentWidget created to address RTL issues
  22 // in picker dialogs. We are responsible for destroying these.
  23 class AutoDestroyTmpWindow
  24 {
  25 public:
  26   explicit AutoDestroyTmpWindow(HWND aTmpWnd) :
  27     mWnd(aTmpWnd) {
  28   }
  29
  30   ~AutoDestroyTmpWindow() {
  31     if (mWnd)
  32       DestroyWindow(mWnd);
  33   }
  34
  35   inline HWND get() const { return mWnd; }
  36 private:
  37   HWND mWnd;
  38 };
  39
  40 static DWORD ColorStringToRGB(const nsAString& aColor)
  41 {
  42   DWORD result = 0;
  43
  44   for (uint32_t i = 1; i < aColor.Length(); ++i) {
  45     result *= 16;
  46
  47     char16_t c = aColor[i];
  48     if (c >= '0' && c <= '9') {
  49       result += c - '0';
  50     } else if (c >= 'a' && c <= 'f') {
  51       result += 10 + (c - 'a');
  52     } else {
  53       result += 10 + (c - 'A');
  54     }
  55   }
  56
  57   DWORD r = result & 0x00FF0000;
  58   DWORD g = result & 0x0000FF00;
  59   DWORD b = result & 0x000000FF;
  60
  61   r = r >> 16;
  62   b = b << 16;
  63
  64   result = r | g | b;
  65
  66   return result;
  67 }
  68
  69 static nsString ToHexString(BYTE n)
  70 {
  71   nsString result;
  72   if (n <= 0x0F) {
  73     result.Append('0');
  74   }
  75   result.AppendInt(n, 16);
  76   return result;
  77 }
  78
  79
  80 static void
  81 BGRIntToRGBString(DWORD color, nsAString& aResult)
  82 {
  83   BYTE r = GetRValue(color);
  84   BYTE g = GetGValue(color);
  85   BYTE b = GetBValue(color);
  86
  87   aResult.Assign('#');
  88   aResult.Append(ToHexString(r));
  89   aResult.Append(ToHexString(g));
  90   aResult.Append(ToHexString(b));
  91 }
  92 } // anonymous namespace
  93
  94 static AsyncColorChooser* gColorChooser;
  95
  96 AsyncColorChooser::AsyncColorChooser(COLORREF aInitialColor,
  97                                      nsIWidget* aParentWidget,
  98                                      nsIColorPickerShownCallback* aCallback)
  99   : mInitialColor(aInitialColor)
 100   , mColor(aInitialColor)
 101   , mParentWidget(aParentWidget)
 102   , mCallback(aCallback)
 103 {
 104 }
 105
 106 NS_IMETHODIMP
 107 AsyncColorChooser::Run()
 108 {
 109   static COLORREF sCustomColors[16] = {0} ;
 110
 111   MOZ_ASSERT(NS_IsMainThread(),
 112       "Color pickers can only be opened from main thread currently");
 113
 114   // Allow only one color picker to be opened at a time, to workaround bug 944737
 115   if (!gColorChooser) {
 116     mozilla::AutoRestore<AsyncColorChooser*> restoreColorChooser(gColorChooser);
 117     gColorChooser = this;
 118
 119     AutoDestroyTmpWindow adtw((HWND) (mParentWidget.get() ?
 120       mParentWidget->GetNativeData(NS_NATIVE_TMP_WINDOW) : nullptr));
 121
 122     CHOOSECOLOR options;
 123     options.lStructSize   = sizeof(options);
 124     options.hwndOwner     = adtw.get();
 125     options.Flags         = CC_RGBINIT | CC_FULLOPEN | CC_ENABLEHOOK;
 126     options.rgbResult     = mInitialColor;
 127     options.lpCustColors  = sCustomColors;
 128     options.lpfnHook      = HookProc;
 129
 130     mColor = ChooseColor(&options) ? options.rgbResult : mInitialColor;
 131   } else {
 132     NS_WARNING("Currently, it's not possible to open more than one color "
 133                "picker at a time");
 134     mColor = mInitialColor;
 135   }
 136
 137   if (mCallback) {
 138     nsAutoString colorStr;
 139     BGRIntToRGBString(mColor, colorStr);
 140     mCallback->Done(colorStr);
 141   }
 142
 143   return NS_OK;
 144 }
 145
 146 void
 147 AsyncColorChooser::Update(COLORREF aColor)
 148 {
 149   if (mColor != aColor) {
 150     mColor = aColor;
 151
 152     nsAutoString colorStr;
 153     BGRIntToRGBString(mColor, colorStr);
 154     mCallback->Update(colorStr);
 155   }
 156 }
 157
 158 /* static */ UINT_PTR CALLBACK
 159 AsyncColorChooser::HookProc(HWND aDialog, UINT aMsg,
 160                             WPARAM aWParam, LPARAM aLParam)
 161 {
 162   if (!gColorChooser) {
 163     return 0;
 164   }
 165
 166   if (aMsg == WM_CTLCOLORSTATIC) {
 167     // The color picker does not expose a proper way to retrieve the current
 168     // color, so we need to obtain it from the static control displaying the
 169     // current color instead.
 170     const int kCurrentColorBoxID = 709;
 171     if ((HWND)aLParam == GetDlgItem(aDialog, kCurrentColorBoxID)) {
 172       gColorChooser->Update(GetPixel((HDC)aWParam, 0, 0));
 173     }
 174   }
 175
 176   return 0;
 177 }
 178
 179 ///////////////////////////////////////////////////////////////////////////////
 180 // nsIColorPicker
 181
 182 nsColorPicker::nsColorPicker()
 183 {
 184 }
 185
 186 nsColorPicker::~nsColorPicker()
 187 {
 188 }
 189
 190 NS_IMPL_ISUPPORTS(nsColorPicker, nsIColorPicker)
 191
 192 NS_IMETHODIMP
 193 nsColorPicker::Init(nsIDOMWindow* parent,
 194                     const nsAString& title,
 195                     const nsAString& aInitialColor)
 196 {
 197   NS_PRECONDITION(parent,
 198       "Null parent passed to colorpicker, no color picker for you!");
 199   mParentWidget =  WidgetUtils::DOMWindowToWidget(parent);
 200   mInitialColor = ColorStringToRGB(aInitialColor);
 201   return NS_OK;
 202 }
 203
 204 NS_IMETHODIMP
 205 nsColorPicker::Open(nsIColorPickerShownCallback* aCallback)
 206 {
 207   NS_ENSURE_ARG(aCallback);
 208   nsCOMPtr<nsIRunnable> event = new AsyncColorChooser(mInitialColor,
 209                                                       mParentWidget,
 210                                                       aCallback);
 211   return NS_DispatchToMainThread(event);
 212 }