C++ UIElement::UpdateLayout方法代码示例

void FileSelector::RefreshFiles()
{
    FileSystem* fileSystem = GetSubsystem<FileSystem>();

    ignoreEvents_ = true;

    fileList_->RemoveAllItems();
    fileEntries_.Clear();

    Vector<String> directories;
    Vector<String> files;
    fileSystem->ScanDir(directories, path_, "*", SCAN_DIRS, false);
    fileSystem->ScanDir(files, path_, GetFilter(), SCAN_FILES, false);

    fileEntries_.Reserve(directories.Size() + files.Size());

    for (unsigned i = 0; i < directories.Size(); ++i)
    {
        FileSelectorEntry newEntry;
        newEntry.name_ = directories[i];
        newEntry.directory_ = true;
        fileEntries_.Push(newEntry);
    }

    for (unsigned i = 0; i < files.Size(); ++i)
    {
        FileSelectorEntry newEntry;
        newEntry.name_ = files[i];
        newEntry.directory_ = false;
        fileEntries_.Push(newEntry);
    }

    // Sort and add to the list view
    // While items are being added, disable layout update for performance optimization
    Sort(fileEntries_.Begin(), fileEntries_.End(), CompareEntries);
    UIElement* listContent = fileList_->GetContentElement();
    listContent->DisableLayoutUpdate();
    for (unsigned i = 0; i < fileEntries_.Size(); ++i)
    {
        String displayName;
        if (fileEntries_[i].directory_)
            displayName = "<DIR> " + fileEntries_[i].name_;
        else
            displayName = fileEntries_[i].name_;

        Text* entryText = new Text(context_);
        fileList_->AddItem(entryText);
        entryText->SetText(displayName);
        entryText->SetStyle("FileSelectorListText");
    }
    listContent->EnableLayoutUpdate();
    listContent->UpdateLayout();

    ignoreEvents_ = false;

    // Clear filename from the previous dir so that there is no confusion
    SetFileName(String::EMPTY);
    lastUsedFilter_ = GetFilter();
}

void DropDownList::OnShowPopup()
{
    // Resize the popup to match the size of the list content, and optionally match the button width
    UIElement* content = listView_->GetContentElement();
    content->UpdateLayout();
    const IntVector2& contentSize = content->GetSize();
    const IntRect& border = popup_->GetLayoutBorder();
    popup_->SetSize(resizePopup_ ? GetWidth() : contentSize.x_ + border.left_ + border.right_, contentSize.y_ + border.top_ +
        border.bottom_);

    // Check if popup fits below the button. If not, show above instead
    bool showAbove = false;
    UIElement* root = GetRoot();
    if (root)
    {
        const IntVector2& screenPos = GetScreenPosition();
        if (screenPos.y_ + GetHeight() + popup_->GetHeight() > root->GetHeight() && screenPos.y_ - popup_->GetHeight() >= 0)
            showAbove = true;
    }
    SetPopupOffset(0, showAbove ? -popup_->GetHeight() : GetHeight());
}

//.........这里部分代码省略.........
                        printText_.push_back('\n');
                        printToText_.push_back(Min(i, unicodeText_.size() - 1));
                        rowWidth = 0;
                        nextBreak = lineStart = i;
                    }

                    if (i < unicodeText_.size())
                    {
                        // When copying a space, position is allowed to be over row width
                        c = unicodeText_[i];
                        const FontGlyph* glyph = face->GetGlyph(c);
                        if (glyph)
                        {
                            rowWidth += glyph->advanceX_;
                            if (i < unicodeText_.size() - 1)
                                rowWidth += face->GetKerning(c, unicodeText_[i + 1]);
                        }
                        if (rowWidth <= maxWidth)
                        {
                            printText_.push_back(c);
                            printToText_.push_back(i);
                        }
                    }
                }
                else
                {
                    printText_.push_back('\n');
                    printToText_.push_back(Min(i, unicodeText_.size() - 1));
                    rowWidth = 0;
                    nextBreak = lineStart = i;
                }
            }
        }

        rowWidth = 0;

        for (unsigned i = 0; i < printText_.size(); ++i)
        {
            unsigned c = printText_[i];

            if (c != '\n')
            {
                const FontGlyph* glyph = face->GetGlyph(c);
                if (glyph)
                {
                    rowWidth += glyph->advanceX_;
                    if (i < printText_.size() - 1)
                        rowWidth += face->GetKerning(c, printText_[i + 1]);
                }
            }
            else
            {
                width = Max(width, rowWidth);
                height += rowHeight;
                rowWidths_.push_back(rowWidth);
                rowWidth = 0;
            }
        }

        if (rowWidth)
        {
            width = Max(width, rowWidth);
            height += rowHeight;
            rowWidths_.push_back(rowWidth);
        }

        // Set at least one row height even if text is empty
        if (!height)
            height = rowHeight;

        // Set minimum and current size according to the text size, but respect fixed width if set
        if (!IsFixedWidth())
        {
            if (wordWrap_)
                SetMinWidth(0);
            else
            {
                SetMinWidth(width);
                SetWidth(width);
            }
        }
        SetFixedHeight(height);

        charLocationsDirty_ = true;
    }
    else
    {
        // No font, nothing to render
        pageGlyphLocations_.clear();
    }

    // If wordwrap is on, parent may need layout update to correct for overshoot in size. However, do not do this when the
    // update is a response to resize, as that could cause infinite recursion
    if (wordWrap_ && !onResize)
    {
        UIElement* parent = GetParent();
        if (parent && parent->GetLayoutMode() != LM_FREE)
            parent->UpdateLayout();
    }
}