Border Layout Example | Qt Widgets 5.12.8

- Qt 5.12
- Qt Widgets
- Border Layout Example
- Qt 5.12.8 Reference Documentation

# Border Layout Example

Shows how to arrange child widgets along a border.

Border Layout implements a layout that arranges child widgets to surround the main area.

The constructor of the Window class creates a QTextBrowser object, to which a BorderLayout named `layout` is added. The declaration of the BorderLayout class is quoted at the end of this document.

     Window::Window()
     {
         QTextBrowser *centralWidget = new QTextBrowser;
         centralWidget->setPlainText(tr("Central widget"));

         BorderLayout *layout = new BorderLayout;

Several labeled widgets are added to `layout` with the orientation `Center`, `North`, `West`, `East 1`, `East 2`, and `South`.

         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"));

createLabel() in class `Window` sets the text of the labeled widgets and the style.

     QLabel *Window::createLabel(const QString &text)
     {
         QLabel *label = new QLabel(text);
         label->setFrameStyle(QFrame::Box | QFrame::Raised);
         return label;
     }

Class BorderLayout contains all the utilitarian functions for formatting the widgets it contains.

     class BorderLayout : public QLayout
     {
     public:
         enum Position { West, North, South, East, Center };

         explicit BorderLayout(QWidget *parent, int margin = 0, int spacing = -1);
         BorderLayout(int spacing = -1);
         ~BorderLayout();

         void addItem(QLayoutItem *item) override;
         void addWidget(QWidget *widget, Position position);
         Qt::Orientations expandingDirections() const override;
         bool hasHeightForWidth() const override;
         int count() const override;
         QLayoutItem *itemAt(int index) const override;
         QSize minimumSize() const override;
         void setGeometry(const QRect &rect) override;
         QSize sizeHint() const override;
         QLayoutItem *takeAt(int index) override;

         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;
     };

For more information, visit the Layout Management page.

## Running the Example

To run the example from Qt Creator, open the Welcome mode and select the example from Examples. For more information, visit Building and Running an Example.

Files:

- layouts/borderlayout/borderlayout.cpp
- layouts/borderlayout/borderlayout.h
- layouts/borderlayout/borderlayout.pro
- layouts/borderlayout/main.cpp
- layouts/borderlayout/window.cpp
- layouts/borderlayout/window.h