okular/ui/toggleactionmenu.cpp

/***************************************************************************
 *   Copyright (C) 2019 by David Hurka <david.hurka@mailbox.org>           *
 *                                                                         *
 *   Inspired by and replacing toolaction.h by:                            *
 *     Copyright (C) 2004-2006 by Albert Astals Cid <aacid@kde.org>        *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 ***************************************************************************/

#include "toggleactionmenu.h"

#include <QPointer>
#include <QMenu>

ToggleActionMenu::ToggleActionMenu( QObject * parent )
    : ToggleActionMenu( QIcon(), QString(), parent )
{
}

ToggleActionMenu::ToggleActionMenu( const QString &text, QObject * parent )
    : ToggleActionMenu( QIcon(), text, parent )
{
}

ToggleActionMenu::ToggleActionMenu( const QIcon &icon,
                                    const QString &text,
                                    QObject * parent,
                                    PopupMode popupMode,
                                    MenuLogic logic )
    : KActionMenu( icon, text, parent ),
    m_defaultAction( nullptr ),
    m_suggestedDefaultAction( nullptr ),
    m_menuLogic( logic )
{
    connect( this, &QAction::changed, this, &ToggleActionMenu::updateButtons );

    if ( popupMode == DelayedPopup )
    {
        setDelayed( true );
    }
    else
    {
        setDelayed( false );
    }
    setStickyMenu( false );

    if ( logic & ImplicitDefaultAction )
    {
        connect( menu(), &QMenu::triggered, this, &ToggleActionMenu::setDefaultAction );
    }
}

QWidget * ToggleActionMenu::createWidget( QWidget * parent )
{
    QToolButton * button = qobject_cast< QToolButton * >( KActionMenu::createWidget( parent ) );
    if ( !button ) {
        // This function is used to add a button into the toolbar.
        // KActionMenu will plug itself as QToolButton.
        // So, if no QToolButton was returned, this was not called the intended way.
        return button;
    }

    // Remove this menu action from the button,
    // so it doesn't compose a menu of this menu action and its own menu.
    button->removeAction( this );
    // The button has lost the menu now, let it use the correct menu.
    button->setMenu( menu() );

    m_buttons.append( QPointer< QToolButton >( button ) );

    // Apply other properties to the button.
    updateButtons();

    return button;
}

void ToggleActionMenu::setDefaultAction( QAction *action )
{
    m_defaultAction = action;
    updateButtons();
}

void ToggleActionMenu::suggestDefaultAction( QAction *action )
{
    m_suggestedDefaultAction = action;
}

QAction * ToggleActionMenu::checkedAction( QMenu *menu ) const
{
    // Look at each action a in the menu whether it is checked.
    // If a is a menu, recursively call checkedAction().
    const QList<QAction*> actions = menu->actions();
    for ( QAction * a : actions )
    {
        if ( a->isChecked() )
        {
            return a;
        }
        else if ( a->menu() )
        {
            QAction * b = checkedAction( a->menu() );
            if ( b )
            {
                return b;
            }
        }
    }
    return nullptr;
}

void ToggleActionMenu::updateButtons()
{
    for ( const QPointer< QToolButton > &button : qAsConst( m_buttons ) )
    {
        if ( button )
        {
            button->setDefaultAction( defaultAction() );

            // Override some properties of the default action,
            // where the property of this menu makes more sense.
            button->setEnabled( isEnabled() );

            if ( delayed() )
            {
                button->setPopupMode( QToolButton::DelayedPopup );
            }
            else if ( stickyMenu() )
            {
                button->setPopupMode( QToolButton::InstantPopup );
            }
            else
            {
                button->setPopupMode( QToolButton::MenuButtonPopup );
            }
        }
    }
}

QAction * ToggleActionMenu::defaultAction()
{
    if ( ( m_menuLogic & ImplicitDefaultAction ) && !m_defaultAction )
    {
        m_defaultAction = checkedAction( menu() );
    }
    if ( !m_defaultAction )
    {
        m_defaultAction = m_suggestedDefaultAction;
    }
    return m_defaultAction;
}