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 void ChromeObserver::SetDrawsTitle(bool aState) {
  68   nsIWidget* mainWidget = GetWindowWidget();
  69   if (mainWidget) {
  70     // We can do this synchronously because SetDrawsTitle doesn't have any
  71     // synchronous effects apart from a harmless invalidation.
  72     mainWidget->SetDrawsTitle(aState);
  73   }
  74 }
  75
  76 class MarginSetter : public Runnable {
  77  public:
  78   explicit MarginSetter(nsIWidget* aWidget)
  79       : mozilla::Runnable("MarginSetter"),
  80         mWidget(aWidget),
  81         mMargin(-1, -1, -1, -1) {}
  82   MarginSetter(nsIWidget* aWidget, const LayoutDeviceIntMargin& aMargin)
  83       : mozilla::Runnable("MarginSetter"), mWidget(aWidget), mMargin(aMargin) {}
  84
  85   NS_IMETHOD Run() override {
  86     // SetNonClientMargins can dispatch native events, hence doing
  87     // it off a script runner.
  88     mWidget->SetNonClientMargins(mMargin);
  89     return NS_OK;
  90   }
  91
  92  private:
  93   nsCOMPtr<nsIWidget> mWidget;
  94   LayoutDeviceIntMargin mMargin;
  95 };
  96
  97 void ChromeObserver::SetChromeMargins(const nsAttrValue* aValue) {
  98   if (!aValue) return;
  99
 100   nsIWidget* mainWidget = GetWindowWidget();
 101   if (!mainWidget) return;
 102
 103   // top, right, bottom, left - see nsAttrValue
 104   nsAutoString tmp;
 105   aValue->ToString(tmp);
 106   nsIntMargin margins;
 107   if (nsContentUtils::ParseIntMarginValue(tmp, margins)) {
 108     nsContentUtils::AddScriptRunner(new MarginSetter(
 109         mainWidget, LayoutDeviceIntMargin::FromUnknownMargin(margins)));
 110   }
 111 }
 112
 113 void ChromeObserver::AttributeChanged(dom::Element* aElement,
 114                                       int32_t aNamespaceID, nsAtom* aName,
 115                                       int32_t aModType,
 116                                       const nsAttrValue* aOldValue) {
 117   // We only care about changes to the root element.
 118   if (!mDocument || aElement != mDocument->GetRootElement()) {
 119     return;
 120   }
 121
 122   const nsAttrValue* value = aElement->GetParsedAttr(aName, aNamespaceID);
 123   if (value) {
 124     // Hide chrome if needed
 125     if (aName == nsGkAtoms::hidechrome) {
 126       HideWindowChrome(value->Equals(u"true"_ns, eCaseMatters));
 127     } else if (aName == nsGkAtoms::chromemargin) {
 128       SetChromeMargins(value);
 129     }
 130     // title and drawintitlebar are settable on
 131     // any root node (windows, dialogs, etc)
 132     else if (aName == nsGkAtoms::title) {
 133       mDocument->NotifyPossibleTitleChange(false);
 134     } else if (aName == nsGkAtoms::drawtitle) {
 135       SetDrawsTitle(value->Equals(u"true"_ns, eCaseMatters));
 136     } else if (aName == nsGkAtoms::localedir) {
 137       // if the localedir changed on the root element, reset the document
 138       // direction
 139       mDocument->ResetDocumentDirection();
 140     }
 141   } else {
 142     if (aName == nsGkAtoms::hidechrome) {
 143       HideWindowChrome(false);
 144     } else if (aName == nsGkAtoms::chromemargin) {
 145       ResetChromeMargins();
 146     } else if (aName == nsGkAtoms::localedir) {
 147       // if the localedir changed on the root element, reset the document
 148       // direction
 149       mDocument->ResetDocumentDirection();
 150     } else if (aName == nsGkAtoms::drawtitle) {
 151       SetDrawsTitle(false);
 152     }
 153   }
 154 }
 155
 156 void ChromeObserver::NodeWillBeDestroyed(nsINode* aNode) {
 157   mDocument = nullptr;
 158 }
 159
 160 void ChromeObserver::ResetChromeMargins() {
 161   nsIWidget* mainWidget = GetWindowWidget();
 162   if (!mainWidget) return;
 163   // See nsIWidget
 164   nsContentUtils::AddScriptRunner(new MarginSetter(mainWidget));
 165 }
 166
 167 nsresult ChromeObserver::HideWindowChrome(bool aShouldHide) {
 168   // only top level chrome documents can hide the window chrome
 169   if (!mDocument->IsRootDisplayDocument()) return NS_OK;
 170
 171   nsPresContext* presContext = mDocument->GetPresContext();
 172
 173   if (presContext && presContext->IsChrome()) {
 174     nsIFrame* frame = mDocument->GetDocumentElement()->GetPrimaryFrame();
 175
 176     if (frame) {
 177       nsView* view = frame->GetClosestView();
 178
 179       if (view) {
 180         nsIWidget* w = view->GetWidget();
 181         NS_ENSURE_STATE(w);
 182         w->HideWindowChrome(aShouldHide);
 183       }
 184     }
 185   }
 186
 187   return NS_OK;
 188 }
 189
 190 }  // namespace mozilla::dom