Quelle nsComboboxControlFrame.cpp Sprache: C

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsComboboxControlFrame.h"

#include "gfxContext.h"
#include "gfxUtils.h"
#include "nsCOMPtr.h"
#include "nsDeviceContext.h"
#include "nsFocusManager.h"
#include "nsGkAtoms.h"
#include "nsHTMLParts.h"
#include "nsIFormControl.h"
#include "nsILayoutHistoryState.h"
#include "nsListControlFrame.h"
#include "nsPIDOMWindow.h"
#include "nsView.h"
#include "nsViewManager.h"
#include "nsISelectControlFrame.h"
#include "nsContentUtils.h"
#include "mozilla/dom/Event.h"
#include "mozilla/dom/HTMLSelectElement.h"
#include "mozilla/dom/Document.h"
#include "mozilla/ServoStyleSet.h"
#include "nsNodeInfoManager.h"
#include "nsContentCreatorFunctions.h"
#include "nsLayoutUtils.h"
#include "nsDisplayList.h"
#include "nsITheme.h"
#include "nsStyleConsts.h"
#include "nsTextFrameUtils.h"
#include "nsTextRunTransformations.h"
#include "HTMLSelectEventListener.h"
#include "mozilla/Likely.h"
#include <algorithm>
#include "nsTextNode.h"
#include "mozilla/AsyncEventDispatcher.h"
#include "mozilla/LookAndFeel.h"
#include "mozilla/PresShell.h"
#include "mozilla/PresShellInlines.h"

using namespace mozilla;
using namespace mozilla::gfx;

NS_IMETHODIMP
nsComboboxControlFrame::RedisplayTextEvent::Run() {
  if (mControlFrame) {
    mControlFrame->HandleRedisplayTextEvent();
  }
  return NS_OK;
}

// Drop down list event management.
// The combo box uses the following strategy for managing the drop-down list.
// If the combo box or its arrow button is clicked on the drop-down list is
// displayed If mouse exits the combo box with the drop-down list displayed the
// drop-down list is asked to capture events The drop-down list will capture all
// events including mouse down and up and will always return with
// ListWasSelected method call regardless of whether an item in the list was
// actually selected.
// The ListWasSelected code will turn off mouse-capture for the drop-down list.
// The drop-down list does not explicitly set capture when it is in the
// drop-down mode.

nsComboboxControlFrame* NS_NewComboboxControlFrame(PresShell* aPresShell,
                                                   ComputedStyle* aStyle) {
  nsComboboxControlFrame* it = new (aPresShell)
      nsComboboxControlFrame(aStyle, aPresShell->GetPresContext());
  return it;
}

NS_IMPL_FRAMEARENA_HELPERS(nsComboboxControlFrame)

nsComboboxControlFrame::nsComboboxControlFrame(ComputedStyle* aStyle,
                                               nsPresContext* aPresContext)
    : nsHTMLButtonControlFrame(aStyle, aPresContext, kClassID) {}

nsComboboxControlFrame::~nsComboboxControlFrame() = default;

NS_QUERYFRAME_HEAD(nsComboboxControlFrame)
  NS_QUERYFRAME_ENTRY(nsComboboxControlFrame)
  NS_QUERYFRAME_ENTRY(nsIAnonymousContentCreator)
  NS_QUERYFRAME_ENTRY(nsISelectControlFrame)
NS_QUERYFRAME_TAIL_INHERITING(nsHTMLButtonControlFrame)

#ifdef ACCESSIBILITY
a11y::AccType nsComboboxControlFrame::AccessibleType() {
  return a11y::eHTMLComboboxType;
}
#endif

bool nsComboboxControlFrame::HasDropDownButton() const {
  const nsStyleDisplay* disp = StyleDisplay();
  // FIXME(emilio): Blink also shows this for menulist-button and such... Seems
  // more similar to our mac / linux implementation.
  return disp->EffectiveAppearance() == StyleAppearance::Menulist &&
         (!IsThemed(disp) ||
          PresContext()->Theme()->ThemeNeedsComboboxDropmarker());
}

nscoord nsComboboxControlFrame::DropDownButtonISize() {
  if (!HasDropDownButton()) {
    return 0;
  }

  nsPresContext* pc = PresContext();
  LayoutDeviceIntSize dropdownButtonSize = pc->Theme()->GetMinimumWidgetSize(
      pc, this, StyleAppearance::MozMenulistArrowButton);
  return pc->DevPixelsToAppUnits(dropdownButtonSize.width);
}

int32_t nsComboboxControlFrame::CharCountOfLargestOptionForInflation() const {
  uint32_t maxLength = 0;
  nsAutoString label;
  for (auto i : IntegerRange(Select().Options()->Length())) {
    GetOptionText(i, label);
    maxLength = std::max(
        maxLength,
        nsTextFrameUtils::ComputeApproximateLengthWithWhitespaceCompression(
            label, StyleText()));
  }
  if (MOZ_UNLIKELY(maxLength > uint32_t(INT32_MAX))) {
    return INT32_MAX;
  }
  return int32_t(maxLength);
}

nscoord nsComboboxControlFrame::GetLongestOptionISize(
    gfxContext* aRenderingContext) const {
  // Compute the width of each option's (potentially text-transformed) text,
  // and use the widest one as part of our intrinsic size.
  nscoord maxOptionSize = 0;
  nsAutoString label;
  nsAutoString transformedLabel;
  RefPtr<nsFontMetrics> fm =
      nsLayoutUtils::GetInflatedFontMetricsForFrame(this);
  const nsStyleText* textStyle = StyleText();
  auto textTransform = textStyle->mTextTransform.IsNone()
                           ? Nothing()
                           : Some(textStyle->mTextTransform);
  nsAtom* language = StyleFont()->mLanguage;
  AutoTArray<bool, 50> charsToMergeArray;
  AutoTArray<bool, 50> deletedCharsArray;
  for (auto i : IntegerRange(Select().Options()->Length())) {
    GetOptionText(i, label);
    const nsAutoString* stringToUse = &label;
    if (textTransform ||
        textStyle->mWebkitTextSecurity != StyleTextSecurity::None) {
      transformedLabel.Truncate();
      charsToMergeArray.SetLengthAndRetainStorage(0);
      deletedCharsArray.SetLengthAndRetainStorage(0);
      nsCaseTransformTextRunFactory::TransformString(
          label, transformedLabel, textTransform,
          textStyle->TextSecurityMaskChar(),
          /* aCaseTransformsOnly = */ false, language, charsToMergeArray,
          deletedCharsArray);
      stringToUse = &transformedLabel;
    }
    maxOptionSize = std::max(maxOptionSize,
                             nsLayoutUtils::AppUnitWidthOfStringBidi(
                                 *stringToUse, this, *fm, *aRenderingContext));
  }
  if (maxOptionSize) {
    // HACK: Add one app unit to workaround silly Netgear router styling, see
    // bug 1769580. In practice since this comes from font metrics is unlikely
    // to be perceivable.
    maxOptionSize += 1;
  }
  return maxOptionSize;
}

nscoord nsComboboxControlFrame::IntrinsicISize(const IntrinsicSizeInput& aInput,
                                               IntrinsicISizeType aType) {
  Maybe<nscoord> containISize = ContainIntrinsicISize(NS_UNCONSTRAINEDSIZE);
  if (containISize && *containISize != NS_UNCONSTRAINEDSIZE) {
    return *containISize;
  }

  nscoord displayISize = 0;
  if (!containISize && !StyleContent()->mContent.IsNone()) {
    displayISize += GetLongestOptionISize(aInput.mContext);
  }

  // Add room for the dropmarker button (if there is one).
  displayISize += DropDownButtonISize();
  return displayISize;
}

dom::HTMLSelectElement& nsComboboxControlFrame::Select() const {
  return *static_cast<dom::HTMLSelectElement*>(GetContent());
}

void nsComboboxControlFrame::GetOptionText(uint32_t aIndex,
                                           nsAString& aText) const {
  aText.Truncate();
  if (Element* el = Select().Options()->GetElementAt(aIndex)) {
    static_cast<dom::HTMLOptionElement*>(el)->GetRenderedLabel(aText);
  }
}

void nsComboboxControlFrame::Reflow(nsPresContext* aPresContext,
                                    ReflowOutput& aDesiredSize,
                                    const ReflowInput& aReflowInput,
                                    nsReflowStatus& aStatus) {
  MarkInReflow();
  MOZ_ASSERT(aStatus.IsEmpty(), "Caller should pass a fresh reflow status!");
  // Constraints we try to satisfy:

  // 1) Default inline size of button is the vertical scrollbar size
  // 2) If the inline size of button is bigger than our inline size, set
  //    inline size of button to 0.
  // 3) Default block size of button is block size of display area
  // 4) Inline size of display area is whatever is left over from our
  //    inline size after allocating inline size for the button.
  // Make sure the displayed text is the same as the selected option,
  // bug 297389.
  mDisplayedIndex = Select().SelectedIndex();

  // In dropped down mode the "selected index" is the hovered menu item,
  // we want the last selected item which is |mDisplayedIndex| in this case.
  RedisplayText();

  WritingMode wm = aReflowInput.GetWritingMode();

  // Check if the theme specifies a minimum size for the dropdown button
  // first.
  const nscoord buttonISize = DropDownButtonISize();
  const auto padding = aReflowInput.ComputedLogicalPadding(wm);

  // We ignore inline-end-padding (by adding it to our label box size) if we
  // have a dropdown button, so that the button aligns with the end of the
  // padding box.
  mDisplayISize = aReflowInput.ComputedISize() - buttonISize;
  if (buttonISize) {
    mDisplayISize += padding.IEnd(wm);
  }

  nsHTMLButtonControlFrame::Reflow(aPresContext, aDesiredSize, aReflowInput,
                                   aStatus);
}

void nsComboboxControlFrame::Init(nsIContent* aContent,
                                  nsContainerFrame* aParent,
                                  nsIFrame* aPrevInFlow) {
  nsHTMLButtonControlFrame::Init(aContent, aParent, aPrevInFlow);

  mEventListener = new HTMLSelectEventListener(
      Select(), HTMLSelectEventListener::SelectType::Combobox);
}

nsresult nsComboboxControlFrame::RedisplaySelectedText() {
  nsAutoScriptBlocker scriptBlocker;
  mDisplayedIndex = Select().SelectedIndex();
  return RedisplayText();
}

nsresult nsComboboxControlFrame::RedisplayText() {
  nsString previewValue;
  nsString previousText(mDisplayedOptionTextOrPreview);

  Select().GetPreviewValue(previewValue);
  // Get the text to display
  if (!previewValue.IsEmpty()) {
    mDisplayedOptionTextOrPreview = previewValue;
  } else if (mDisplayedIndex != -1 && !StyleContent()->mContent.IsNone()) {
    GetOptionText(mDisplayedIndex, mDisplayedOptionTextOrPreview);
  } else {
    mDisplayedOptionTextOrPreview.Truncate();
  }

  // Send reflow command because the new text maybe larger
  nsresult rv = NS_OK;
  if (!previousText.Equals(mDisplayedOptionTextOrPreview)) {
    // Don't call ActuallyDisplayText(true) directly here since that could cause
    // recursive frame construction. See bug 283117 and the comment in
    // HandleRedisplayTextEvent() below.

    // Revoke outstanding events to avoid out-of-order events which could mean
    // displaying the wrong text.
    mRedisplayTextEvent.Revoke();

    NS_ASSERTION(!nsContentUtils::IsSafeToRunScript(),
                 "If we happen to run our redisplay event now, we might kill "
                 "ourselves!");
    mRedisplayTextEvent = new RedisplayTextEvent(this);
    nsContentUtils::AddScriptRunner(mRedisplayTextEvent.get());
  }
  return rv;
}

void nsComboboxControlFrame::HandleRedisplayTextEvent() {
  // First, make sure that the content model is up to date and we've constructed
  // the frames for all our content in the right places. Otherwise they'll end
  // up under the wrong insertion frame when we ActuallyDisplayText, since that
  // flushes out the content sink by calling SetText on a DOM node with aNotify
  // set to true.  See bug 289730.
  AutoWeakFrame weakThis(this);
  PresContext()->Document()->FlushPendingNotifications(
      FlushType::ContentAndNotify);
  if (!weakThis.IsAlive()) {
    return;
  }
  mRedisplayTextEvent.Forget();
  ActuallyDisplayText(true);
  // Note: `this` might be dead here.
}

void nsComboboxControlFrame::ActuallyDisplayText(bool aNotify) {
  RefPtr<dom::Text> displayContent = mDisplayLabel->GetFirstChild()->AsText();
  // Have to use a space character of some sort for line-block-size calculations
  // to be right. Also, the space character must be zero-width in order for the
  // inline-size calculations to be consistent between size-contained comboboxes
  // vs. empty comboboxes.
  //
  // XXXdholbert Does this space need to be "non-breaking"? I'm not sure if it
  // matters, but we previously had a comment here (added in 2002) saying "Have
  // to use a non-breaking space for line-height calculations to be right". So
  // I'll stick with a non-breaking space for now...
  displayContent->SetText(mDisplayedOptionTextOrPreview.IsEmpty()
                              ? u"\ufeff"_ns
                              : mDisplayedOptionTextOrPreview,
                          aNotify);
}

bool nsComboboxControlFrame::IsDroppedDown() const {
  return Select().OpenInParentProcess();
}

//----------------------------------------------------------------------
// nsISelectControlFrame
//----------------------------------------------------------------------
NS_IMETHODIMP
nsComboboxControlFrame::DoneAddingChildren(bool aIsDone) { return NS_OK; }

NS_IMETHODIMP
nsComboboxControlFrame::AddOption(int32_t aIndex) {
  if (aIndex <= mDisplayedIndex) {
    ++mDisplayedIndex;
  }

  return NS_OK;
}

NS_IMETHODIMP
nsComboboxControlFrame::RemoveOption(int32_t aIndex) {
  if (Select().Options()->Length()) {
    if (aIndex < mDisplayedIndex) {
      --mDisplayedIndex;
    } else if (aIndex == mDisplayedIndex) {
      mDisplayedIndex = 0;  // IE6 compat
      RedisplayText();
    }
  } else {
    // If we removed the last option, we need to blank things out
    mDisplayedIndex = -1;
    RedisplayText();
  }
  return NS_OK;
}

NS_IMETHODIMP_(void)
nsComboboxControlFrame::OnSetSelectedIndex(int32_t aOldIndex,
                                           int32_t aNewIndex) {
  nsAutoScriptBlocker scriptBlocker;
  mDisplayedIndex = aNewIndex;
  RedisplayText();
}

// End nsISelectControlFrame
//----------------------------------------------------------------------

nsresult nsComboboxControlFrame::HandleEvent(nsPresContext* aPresContext,
                                             WidgetGUIEvent* aEvent,
                                             nsEventStatus* aEventStatus) {
  NS_ENSURE_ARG_POINTER(aEventStatus);

  if (nsEventStatus_eConsumeNoDefault == *aEventStatus) {
    return NS_OK;
  }

  return nsHTMLButtonControlFrame::HandleEvent(aPresContext, aEvent,
                                               aEventStatus);
}

nsresult nsComboboxControlFrame::CreateAnonymousContent(
    nsTArray<ContentInfo>& aElements) {
  dom::Document* doc = mContent->OwnerDoc();
  mDisplayLabel = doc->CreateHTMLElement(nsGkAtoms::label);

  {
    RefPtr<nsTextNode> text = doc->CreateEmptyTextNode();
    mDisplayLabel->AppendChildTo(text, false, IgnoreErrors());
  }

  // set the value of the text node
  mDisplayedIndex = Select().SelectedIndex();
  if (mDisplayedIndex != -1) {
    GetOptionText(mDisplayedIndex, mDisplayedOptionTextOrPreview);
  }
  ActuallyDisplayText(false);

  aElements.AppendElement(mDisplayLabel);
  if (HasDropDownButton()) {
    mButtonContent = mContent->OwnerDoc()->CreateHTMLElement(nsGkAtoms::button);
    {
      // This gives the button a reasonable height. This could be done via CSS
      // instead, but relative font units like 1lh don't play very well with our
      // font inflation implementation, so we do it this way instead.
      RefPtr<nsTextNode> text = doc->CreateTextNode(u"\ufeff"_ns);
      mButtonContent->AppendChildTo(text, false, IgnoreErrors());
    }
    // Make someone to listen to the button.
    mButtonContent->SetAttr(kNameSpaceID_None, nsGkAtoms::type, u"button"_ns,
                            false);
    // Set tabindex="-1" so that the button is not tabbable
    mButtonContent->SetAttr(kNameSpaceID_None, nsGkAtoms::tabindex, u"-1"_ns,
                            false);
    aElements.AppendElement(mButtonContent);
  }

  return NS_OK;
}

void nsComboboxControlFrame::AppendAnonymousContentTo(
    nsTArray<nsIContent*>& aElements, uint32_t aFilter) {
  if (mDisplayLabel) {
    aElements.AppendElement(mDisplayLabel);
  }

  if (mButtonContent) {
    aElements.AppendElement(mButtonContent);
  }
}

namespace mozilla {

class ComboboxLabelFrame final : public nsBlockFrame {
public:
  NS_DECL_QUERYFRAME
  NS_DECL_FRAMEARENA_HELPERS(ComboboxLabelFrame)

#ifdef DEBUG_FRAME_DUMP
  nsresult GetFrameName(nsAString& aResult) const final {
    return MakeFrameName(u"ComboboxLabel"_ns, aResult);
  }
#endif

  void Reflow(nsPresContext* aPresContext, ReflowOutput& aDesiredSize,
              const ReflowInput& aReflowInput, nsReflowStatus& aStatus) final;

public:
  ComboboxLabelFrame(ComputedStyle* aStyle, nsPresContext* aPresContext)
      : nsBlockFrame(aStyle, aPresContext, kClassID) {}
};

NS_QUERYFRAME_HEAD(ComboboxLabelFrame)
  NS_QUERYFRAME_ENTRY(ComboboxLabelFrame)
NS_QUERYFRAME_TAIL_INHERITING(nsBlockFrame)
NS_IMPL_FRAMEARENA_HELPERS(ComboboxLabelFrame)

void ComboboxLabelFrame::Reflow(nsPresContext* aPresContext,
                                ReflowOutput& aDesiredSize,
                                const ReflowInput& aReflowInput,
                                nsReflowStatus& aStatus) {
  MOZ_ASSERT(aStatus.IsEmpty(), "Caller should pass a fresh reflow status!");

  const nsComboboxControlFrame* combobox =
      do_QueryFrame(GetParent()->GetParent());
  MOZ_ASSERT(combobox, "Combobox's frame tree is wrong!");
  MOZ_ASSERT(aReflowInput.ComputedPhysicalBorderPadding() == nsMargin(),
             "We shouldn't have border and padding in UA!");

  ReflowInput state(aReflowInput);
  state.SetComputedISize(combobox->mDisplayISize);
  nsBlockFrame::Reflow(aPresContext, aDesiredSize, state, aStatus);
  aStatus.Reset();  // this type of frame can't be split
}

}  // namespace mozilla

nsIFrame* NS_NewComboboxLabelFrame(PresShell* aPresShell,
                                   ComputedStyle* aStyle) {
  return new (aPresShell)
      ComboboxLabelFrame(aStyle, aPresShell->GetPresContext());
}

void nsComboboxControlFrame::Destroy(DestroyContext& aContext) {
  // Revoke any pending RedisplayTextEvent
  mRedisplayTextEvent.Revoke();
  mEventListener->Detach();

  aContext.AddAnonymousContent(mDisplayLabel.forget());
  aContext.AddAnonymousContent(mButtonContent.forget());
  nsHTMLButtonControlFrame::Destroy(aContext);
}

//---------------------------------------------------------
// gets the content (an option) by index and then set it as
// being selected or not selected
//---------------------------------------------------------
NS_IMETHODIMP
nsComboboxControlFrame::OnOptionSelected(int32_t aIndex, bool aSelected) {
  if (aSelected) {
    nsAutoScriptBlocker blocker;
    mDisplayedIndex = aIndex;
    RedisplayText();
  } else {
    AutoWeakFrame weakFrame(this);
    RedisplaySelectedText();
    if (weakFrame.IsAlive()) {
      FireValueChangeEvent();  // Fire after old option is unselected
    }
  }
  return NS_OK;
}

void nsComboboxControlFrame::FireValueChangeEvent() {
  // Fire ValueChange event to indicate data value of combo box has changed
  // FIXME(emilio): This shouldn't be exposed to content.
  nsContentUtils::AddScriptRunner(new AsyncEventDispatcher(
      mContent, u"ValueChange"_ns, CanBubble::eYes, ChromeOnlyDispatch::eNo));
}

quality97%

¤ Dauer der Verarbeitung: 0.2 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.

Bemerkung:

Die farbliche Syntaxdarstellung ist noch experimentell.