qt-creator/src/tools/qml/qmlobserver/editor/crumblepath.cpp

#include "crumblepath.h"

#include <QHBoxLayout>
#include <QPushButton>
#include <QStyle>
#include <QResizeEvent>

namespace QmlViewer {

static const int ArrowBorderSize = 12;

class CrumblePathButton : public QPushButton
{
public:
    enum SegmentType {
        LastSegment = 1,
        MiddleSegment = 2,
        FirstSegment = 4
    };

    explicit CrumblePathButton(const QString &title, QWidget *parent = 0);
    void setSegmentType(int type);
private:
    static QString middleSegmentSheet(bool useLeftPadding);
    static QString lastSegmentSheet(bool useLeftPadding);
};

CrumblePathButton::CrumblePathButton(const QString &title, QWidget *parent)
    : QPushButton(title, parent)
{
    setSizePolicy(QSizePolicy::Maximum, QSizePolicy::Fixed);
    setToolTip(title);
    setMinimumHeight(24);
    setMaximumHeight(24);

    setStyleSheet(lastSegmentSheet(true));
}

QString CrumblePathButton::middleSegmentSheet(bool useLeftPadding)
{
    QString sheet = QString(
                "QPushButton {"
                "text-align: left;"
                "color: #eeeeee;"
                "border-image: url(:/qml/images/segment.png)  0 12 0 2;"
                "border-width: 0 12px 0 2px;"
                "padding-left:%1px;"
                "}"
                "QPushButton:hover {"
                "    border-image: url(:/qml/images/segment-hover.png)  0 12 0 2;"
                "}"
                "QPushButton:pressed {"
                "    border-image: url(:/qml/images/segment-selected.png)  0 12 0 2;"
                "}"
                ).arg(useLeftPadding ? "18" : "4");
    return sheet;
}

QString CrumblePathButton::lastSegmentSheet(bool useLeftPadding)
{
    QString sheet = QString(
                "QPushButton {"
                "text-align: left;"
                "color: #eeeeee;"
                "border-image: url(:/qml/images/segment-end.png)  0 2 0 2;"
                "border-width: 0 2px 0 2px;"
                "padding-left:%1px;"
                "}"
                "QPushButton:hover {"
                "    border-image: url(:/qml/images/segment-hover-end.png)  0 2 0 2;"
                "}"
                "QPushButton:pressed {"
                "    border-image: url(:/qml/images/segment-selected-end.png)  0 2 0 2;"
                "}"
                ).arg(useLeftPadding ? "18" : "4");
    return sheet;
}

void CrumblePathButton::setSegmentType(int type)
{
    bool useLeftPadding = !(type & FirstSegment);
    if (type & LastSegment) {
        setStyleSheet(lastSegmentSheet(useLeftPadding));
    } else if (type & MiddleSegment) {
        setStyleSheet(middleSegmentSheet(useLeftPadding));
    }
}

//
// CrumblePath
//
CrumblePath::CrumblePath(QWidget *parent) :
    QWidget(parent)
{
    setMinimumHeight(24);
    setMaximumHeight(24);
}

CrumblePath::~CrumblePath()
{
    qDeleteAll(m_buttons);
    m_buttons.clear();
}

void CrumblePath::pushElement(const QString &title)
{
    CrumblePathButton *newButton = new CrumblePathButton(title, this);
    newButton->hide();
    connect(newButton, SIGNAL(clicked()), SLOT(mapClickToIndex()));
    connect(newButton, SIGNAL(customContextMenuRequested(QPoint)), SLOT(mapContextMenuRequestToIndex()));

    int segType = CrumblePathButton::MiddleSegment;
    if (!m_buttons.isEmpty()) {
        if (m_buttons.length() == 1)
            segType = segType | CrumblePathButton::FirstSegment;
        m_buttons.last()->setSegmentType(segType);
    } else {
        segType = CrumblePathButton::FirstSegment | CrumblePathButton::LastSegment;
        newButton->setSegmentType(segType);
    }
    m_buttons.append(newButton);

    resizeButtons();
}

void CrumblePath::popElement()
{
    QWidget *last = m_buttons.last();
    m_buttons.removeLast();
    last->setParent(0);
    last->deleteLater();

    int segType = CrumblePathButton::MiddleSegment;
    if (!m_buttons.isEmpty()) {
        if (m_buttons.length() == 1)
            segType = CrumblePathButton::FirstSegment | CrumblePathButton::LastSegment;
        m_buttons.last()->setSegmentType(segType);
    }
}

void CrumblePath::clear()
{
    while (!m_buttons.isEmpty()) {
        popElement();
    }
}

void CrumblePath::resizeEvent(QResizeEvent *)
{
    resizeButtons();
}

void CrumblePath::resizeButtons()
{
    Q_ASSERT(!m_buttons.isEmpty());

    int buttonWidth = 0;
    if (m_buttons.length() > 1) {
        QPoint nextElementPosition(0,0);

        m_buttons[0]->raise();
        // rearrange all items so that the first item is on top (added last).
        for(int i = 0; i < m_buttons.length() ; ++i) {
            QWidget *button = m_buttons[i];
            buttonWidth = (width() + ArrowBorderSize * m_buttons.length()) / m_buttons.length();
            button->setMaximumWidth(buttonWidth);
            button->setGeometry(QRect(nextElementPosition, QSize(buttonWidth, button->height())));

            nextElementPosition.rx() += button->width() - ArrowBorderSize;

            button->show();
            if (i > 0)
                button->stackUnder(m_buttons[i - 1]);
        }

    } else {
        QWidget *button = m_buttons[0];
        int buttonWidth = 2 * width() / (3 * m_buttons.length());

        button->setMaximumWidth(buttonWidth);
        button->setGeometry(QRect(QPoint(0, 0), QSize(buttonWidth, button->height())));
        button->show();
    }
}

void CrumblePath::mapClickToIndex()
{
    QObject *element = sender();
    for (int i = 0; i < m_buttons.length(); ++i) {
        if (m_buttons[i] == element) {
            emit elementClicked(i);
            return;
        }
    }
}

void CrumblePath::mapContextMenuRequestToIndex()
{
    QObject *element = sender();
    for (int i = 0; i < m_buttons.length(); ++i) {
        if (m_buttons[i] == element) {
            emit elementContextMenuRequested(i);
            return;
        }
    }
}

} // namespace QmlViewer