extends QLayout to create border layout
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#ifndef BORDERLAYOUT_H
#define BORDERLAYOUT_H
#include <QLayout>
#include <QRect>
#include <QWidgetItem>
class BorderLayout : public QLayout
{
public:
enum Position { West, North, South, East, Center };
BorderLayout(QWidget *parent, int margin = 0, int spacing = -1);
BorderLayout(int spacing = -1);
~BorderLayout();
void addItem(QLayoutItem *item);
void addWidget(QWidget *widget, Position position);
Qt::Orientations expandingDirections() const;
bool hasHeightForWidth() const;
int count() const;
QLayoutItem *itemAt(int index) const;
QSize minimumSize() const;
void setGeometry(const QRect &rect);
QSize sizeHint() const;
QLayoutItem *takeAt(int index);
void add(QLayoutItem *item, Position position);
private:
struct ItemWrapper
{
ItemWrapper(QLayoutItem *i, Position p) {
item = i;
position = p;
}
QLayoutItem *item;
Position position;
};
enum SizeType { MinimumSize, SizeHint };
QSize calculateSize(SizeType sizeType) const;
QList<ItemWrapper *> list;
};
#endif
#include <QtGui>
#include "borderlayout.h"
BorderLayout::BorderLayout(QWidget *parent, int margin, int spacing)
: QLayout(parent)
{
setMargin(margin);
setSpacing(spacing);
}
BorderLayout::BorderLayout(int spacing)
{
setSpacing(spacing);
}
BorderLayout::~BorderLayout()
{
QLayoutItem *l;
while ((l = takeAt(0)))
delete l;
}
void BorderLayout::addItem(QLayoutItem *item)
{
add(item, West);
}
void BorderLayout::addWidget(QWidget *widget, Position position)
{
add(new QWidgetItem(widget), position);
}
Qt::Orientations BorderLayout::expandingDirections() const
{
return Qt::Horizontal | Qt::Vertical;
}
bool BorderLayout::hasHeightForWidth() const
{
return false;
}
int BorderLayout::count() const
{
return list.size();
}
QLayoutItem *BorderLayout::itemAt(int index) const
{
ItemWrapper *wrapper = list.value(index);
if (wrapper)
return wrapper->item;
else
return 0;
}
QSize BorderLayout::minimumSize() const
{
return calculateSize(MinimumSize);
}
void BorderLayout::setGeometry(const QRect &rect)
{
ItemWrapper *center = 0;
int eastWidth = 0;
int westWidth = 0;
int northHeight = 0;
int southHeight = 0;
int centerHeight = 0;
int i;
QLayout::setGeometry(rect);
for (i = 0; i < list.size(); ++i) {
ItemWrapper *wrapper = list.at(i);
QLayoutItem *item = wrapper->item;
Position position = wrapper->position;
if (position == North) {
item->setGeometry(QRect(rect.x(), northHeight, rect.width(),
item->sizeHint().height()));
northHeight += item->geometry().height() + spacing();
} else if (position == South) {
item->setGeometry(QRect(item->geometry().x(),
item->geometry().y(), rect.width(),
item->sizeHint().height()));
southHeight += item->geometry().height() + spacing();
item->setGeometry(QRect(rect.x(),
rect.y() + rect.height() - southHeight + spacing(),
item->geometry().width(),
item->geometry().height()));
} else if (position == Center) {
center = wrapper;
}
}
centerHeight = rect.height() - northHeight - southHeight;
for (i = 0; i < list.size(); ++i) {
ItemWrapper *wrapper = list.at(i);
QLayoutItem *item = wrapper->item;
Position position = wrapper->position;
if (position == West) {
item->setGeometry(QRect(rect.x() + westWidth, northHeight,
item->sizeHint().width(), centerHeight));
westWidth += item->geometry().width() + spacing();
} else if (position == East) {
item->setGeometry(QRect(item->geometry().x(), item->geometry().y(),
item->sizeHint().width(), centerHeight));
eastWidth += item->geometry().width() + spacing();
item->setGeometry(QRect(
rect.x() + rect.width() - eastWidth + spacing(),
northHeight, item->geometry().width(),
item->geometry().height()));
}
}
if (center)
center->item->setGeometry(QRect(westWidth, northHeight,
rect.width() - eastWidth - westWidth,
centerHeight));
}
QSize BorderLayout::sizeHint() const
{
return calculateSize(SizeHint);
}
QLayoutItem *BorderLayout::takeAt(int index)
{
if (index >= 0 && index < list.size()) {
ItemWrapper *layoutStruct = list.takeAt(index);
return layoutStruct->item;
}
return 0;
}
void BorderLayout::add(QLayoutItem *item, Position position)
{
list.append(new ItemWrapper(item, position));
}
QSize BorderLayout::calculateSize(SizeType sizeType) const
{
QSize totalSize;
for (int i = 0; i < list.size(); ++i) {
ItemWrapper *wrapper = list.at(i);
Position position = wrapper->position;
QSize itemSize;
if (sizeType == MinimumSize)
itemSize = wrapper->item->minimumSize();
else // (sizeType == SizeHint)
itemSize = wrapper->item->sizeHint();
if (position == North || position == South || position == Center)
totalSize.rheight() += itemSize.height();
if (position == West || position == East || position == Center)
totalSize.rwidth() += itemSize.width();
}
return totalSize;
}
#ifndef WINDOW_H
#define WINDOW_H
#include <QWidget>
QT_BEGIN_NAMESPACE
class QLabel;
QT_END_NAMESPACE
class Window : public QWidget
{
Q_OBJECT
public:
Window();
private:
QLabel *createLabel(const QString &text);
};
#endif
#include <QtGui>
#include "borderlayout.h"
#include "window.h"
Window::Window()
{
QTextBrowser *centralWidget = new QTextBrowser;
centralWidget->setPlainText(tr("Central widget"));
BorderLayout *layout = new BorderLayout;
layout->addWidget(centralWidget, BorderLayout::Center);
layout->addWidget(createLabel("North"), BorderLayout::North);
layout->addWidget(createLabel("West"), BorderLayout::West);
layout->addWidget(createLabel("East 1"), BorderLayout::East);
layout->addWidget(createLabel("East 2") , BorderLayout::East);
layout->addWidget(createLabel("South"), BorderLayout::South);
setLayout(layout);
setWindowTitle(tr("Border Layout"));
}
QLabel *Window::createLabel(const QString &text)
{
QLabel *label = new QLabel(text);
label->setFrameStyle(QFrame::Box | QFrame::Raised);
return label;
}
#include <QApplication>
#include "window.h"
int main(int argc, char *argv[])
{
QApplication app(argc, argv);
Window window;
window.show();
return app.exec();
}
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