dom/xul/ChromeObserver.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   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 https://mozilla.org/MPL/2.0/. */
   6
   7 #include "ChromeObserver.h"
   8
   9 #include "nsIBaseWindow.h"
  10 #include "nsIWidget.h"
  11 #include "nsIFrame.h"
  12
  13 #include "nsContentUtils.h"
  14 #include "nsView.h"
  15 #include "nsPresContext.h"
  16 #include "mozilla/dom/Document.h"
  17 #include "mozilla/dom/DocumentInlines.h"
  18 #include "mozilla/dom/Element.h"
  19 #include "mozilla/dom/MutationEventBinding.h"
  20 #include "nsXULElement.h"
  21
  22 namespace mozilla::dom {
  23
  24 NS_IMPL_ISUPPORTS(ChromeObserver, nsIMutationObserver)
  25
  26 ChromeObserver::ChromeObserver(Document* aDocument)
  27     : nsStubMutationObserver(), mDocument(aDocument) {}
  28
  29 ChromeObserver::~ChromeObserver() = default;
  30
  31 void ChromeObserver::Init() {
  32   mDocument->AddMutationObserver(this);
  33   Element* rootElement = mDocument->GetRootElement();
  34   if (!rootElement) {
  35     return;
  36   }
  37   nsAutoScriptBlocker scriptBlocker;
  38   uint32_t attributeCount = rootElement->GetAttrCount();
  39   for (uint32_t i = 0; i < attributeCount; i++) {
  40     BorrowedAttrInfo info = rootElement->GetAttrInfoAt(i);
  41     const nsAttrName* name = info.mName;
  42     if (name->LocalName() == nsGkAtoms::chromemargin) {
  43       // Some linux windows managers have an issue when the chrome margin is
  44       // applied while the browser is loading (bug 1598848). For now, skip
  45       // applying this attribute when initializing.
  46       continue;
  47     }
  48     AttributeChanged(rootElement, name->NamespaceID(), name->LocalName(),
  49                      MutationEvent_Binding::ADDITION, nullptr);
  50   }
  51 }
  52
  53 nsIWidget* ChromeObserver::GetWindowWidget() {
  54   // only top level chrome documents can set the titlebar color
  55   if (mDocument && mDocument->IsRootDisplayDocument()) {
  56     nsCOMPtr<nsISupports> container = mDocument->GetContainer();
  57     nsCOMPtr<nsIBaseWindow> baseWindow = do_QueryInterface(container);
  58     if (baseWindow) {
  59       nsCOMPtr<nsIWidget> mainWidget;
  60       baseWindow->GetMainWidget(getter_AddRefs(mainWidget));
  61       return mainWidget;
  62     }
  63   }
  64   return nullptr;
  65 }
  66
  67 class SetDrawInTitleBarEvent : public Runnable {
  68  public:
  69   SetDrawInTitleBarEvent(nsIWidget* aWidget, bool aState)
  70       : mozilla::Runnable("SetDrawInTitleBarEvent"),
  71         mWidget(aWidget),
  72         mState(aState) {}
  73
  74   NS_IMETHOD Run() override {
  75     NS_ASSERTION(mWidget,
  76                  "You shouldn't call this runnable with a null widget!");
  77
  78     mWidget->SetDrawsInTitlebar(mState);
  79     return NS_OK;
  80   }
  81
  82  private:
  83   nsCOMPtr<nsIWidget> mWidget;
  84   bool mState;
  85 };
  86
  87 void ChromeObserver::SetDrawsInTitlebar(bool aState) {
  88   nsIWidget* mainWidget = GetWindowWidget();
  89   if (mainWidget) {
  90     nsContentUtils::AddScriptRunner(
  91         new SetDrawInTitleBarEvent(mainWidget, aState));
  92   }
  93 }
  94
  95 void ChromeObserver::SetDrawsTitle(bool aState) {
  96   nsIWidget* mainWidget = GetWindowWidget();
  97   if (mainWidget) {
  98     // We can do this synchronously because SetDrawsTitle doesn't have any
  99     // synchronous effects apart from a harmless invalidation.
 100     mainWidget->SetDrawsTitle(aState);
 101   }
 102 }
 103
 104 class MarginSetter : public Runnable {
 105  public:
 106   explicit MarginSetter(nsIWidget* aWidget)
 107       : mozilla::Runnable("MarginSetter"),
 108         mWidget(aWidget),
 109         mMargin(-1, -1, -1, -1) {}
 110   MarginSetter(nsIWidget* aWidget, const LayoutDeviceIntMargin& aMargin)
 111       : mozilla::Runnable("MarginSetter"), mWidget(aWidget), mMargin(aMargin) {}
 112
 113   NS_IMETHOD Run() override {
 114     // SetNonClientMargins can dispatch native events, hence doing
 115     // it off a script runner.
 116     mWidget->SetNonClientMargins(mMargin);
 117     return NS_OK;
 118   }
 119
 120  private:
 121   nsCOMPtr<nsIWidget> mWidget;
 122   LayoutDeviceIntMargin mMargin;
 123 };
 124
 125 void ChromeObserver::SetChromeMargins(const nsAttrValue* aValue) {
 126   if (!aValue) return;
 127
 128   nsIWidget* mainWidget = GetWindowWidget();
 129   if (!mainWidget) return;
 130
 131   // top, right, bottom, left - see nsAttrValue
 132   nsIntMargin margins;
 133   bool gotMargins = false;
 134
 135   if (aValue->Type() == nsAttrValue::eIntMarginValue) {
 136     gotMargins = aValue->GetIntMarginValue(margins);
 137   } else {
 138     nsAutoString tmp;
 139     aValue->ToString(tmp);
 140     gotMargins = nsContentUtils::ParseIntMarginValue(tmp, margins);
 141   }
 142   if (gotMargins) {
 143     nsContentUtils::AddScriptRunner(new MarginSetter(
 144         mainWidget, LayoutDeviceIntMargin::FromUnknownMargin(margins)));
 145   }
 146 }
 147
 148 void ChromeObserver::AttributeChanged(dom::Element* aElement,
 149                                       int32_t aNamespaceID, nsAtom* aName,
 150                                       int32_t aModType,
 151                                       const nsAttrValue* aOldValue) {
 152   // We only care about changes to the root element.
 153   if (!mDocument || aElement != mDocument->GetRootElement()) {
 154     return;
 155   }
 156
 157   const nsAttrValue* value = aElement->GetParsedAttr(aName, aNamespaceID);
 158   if (value) {
 159     // Hide chrome if needed
 160     if (aName == nsGkAtoms::hidechrome) {
 161       HideWindowChrome(value->Equals(u"true"_ns, eCaseMatters));
 162     } else if (aName == nsGkAtoms::chromemargin) {
 163       SetChromeMargins(value);
 164     }
 165     // title and drawintitlebar are settable on
 166     // any root node (windows, dialogs, etc)
 167     else if (aName == nsGkAtoms::title) {
 168       mDocument->NotifyPossibleTitleChange(false);
 169     } else if (aName == nsGkAtoms::drawintitlebar) {
 170       SetDrawsInTitlebar(value->Equals(u"true"_ns, eCaseMatters));
 171     } else if (aName == nsGkAtoms::drawtitle) {
 172       SetDrawsTitle(value->Equals(u"true"_ns, eCaseMatters));
 173     } else if (aName == nsGkAtoms::localedir) {
 174       // if the localedir changed on the root element, reset the document
 175       // direction
 176       mDocument->ResetDocumentDirection();
 177     } else if (aName == nsGkAtoms::lwtheme) {
 178       // if the lwtheme changed, make sure to reset the document lwtheme
 179       // cache
 180       mDocument->ResetDocumentLWTheme();
 181     }
 182   } else {
 183     if (aName == nsGkAtoms::hidechrome) {
 184       HideWindowChrome(false);
 185     } else if (aName == nsGkAtoms::chromemargin) {
 186       ResetChromeMargins();
 187     } else if (aName == nsGkAtoms::localedir) {
 188       // if the localedir changed on the root element, reset the document
 189       // direction
 190       mDocument->ResetDocumentDirection();
 191     } else if (aName == nsGkAtoms::lwtheme) {
 192       // if the lwtheme changed, make sure to restyle appropriately
 193       mDocument->ResetDocumentLWTheme();
 194     } else if (aName == nsGkAtoms::drawintitlebar) {
 195       SetDrawsInTitlebar(false);
 196     } else if (aName == nsGkAtoms::drawtitle) {
 197       SetDrawsTitle(false);
 198     }
 199   }
 200 }
 201
 202 void ChromeObserver::NodeWillBeDestroyed(const nsINode* aNode) {
 203   mDocument = nullptr;
 204 }
 205
 206 void ChromeObserver::ResetChromeMargins() {
 207   nsIWidget* mainWidget = GetWindowWidget();
 208   if (!mainWidget) return;
 209   // See nsIWidget
 210   nsContentUtils::AddScriptRunner(new MarginSetter(mainWidget));
 211 }
 212
 213 nsresult ChromeObserver::HideWindowChrome(bool aShouldHide) {
 214   // only top level chrome documents can hide the window chrome
 215   if (!mDocument->IsRootDisplayDocument()) return NS_OK;
 216
 217   nsPresContext* presContext = mDocument->GetPresContext();
 218
 219   if (presContext && presContext->IsChrome()) {
 220     nsIFrame* frame = mDocument->GetDocumentElement()->GetPrimaryFrame();
 221
 222     if (frame) {
 223       nsView* view = frame->GetClosestView();
 224
 225       if (view) {
 226         nsIWidget* w = view->GetWidget();
 227         NS_ENSURE_STATE(w);
 228         w->HideWindowChrome(aShouldHide);
 229       }
 230     }
 231   }
 232
 233   return NS_OK;
 234 }
 235
 236 }  // namespace mozilla::dom