Q3Header Class Reference
[Qt3Support module]

Detailed Description

The Q3Header class provides a header row or column, e.g. for tables and listviews.

This class provides a header, e.g. a vertical header to display row labels, or a horizontal header to display column labels. It is used by Q3Table and Q3ListView for example.

A header is composed of one or more sections, each of which can display a text label and an icon. A sort indicator (an arrow) can also be displayed using setSortIndicator().

Sections are added with addLabel() and removed with removeLabel(). The label and icon are set in addLabel() and can be changed later with setLabel(). Use count() to retrieve the number of sections in the header.

The orientation of the header is set with setOrientation(). If setStretchEnabled() is true, the sections will expand to take up the full width (height for vertical headers) of the header. The user can resize the sections manually if setResizeEnabled() is true. Call adjustHeaderSize() to have the sections resize to occupy the full width (or height).

A section can be moved with moveSection(). If setMovingEnabled() is true (the default)the user may drag a section from one position to another. If a section is moved, the index positions at which sections were added (with addLabel()), may not be the same after the move. You don't have to worry about this in practice because the Q3Header API works in terms of section numbers, so it doesn't matter where a particular section has been moved to.

If you want the current index position of a section call mapToIndex() giving it the section number. (This is the number returned by the addLabel() call which created the section.) If you want to get the section number of a section at a particular index position call mapToSection() giving it the index number.

Here's an example to clarify mapToSection() and mapToIndex():

In the example above, if we wanted to find out which section is at index position 3 we'd call mapToSection(3) and get a section number of 1 since section 1 was moved. Similarly, if we wanted to know which index position section 2 occupied we'd call mapToIndex(2) and get an index of 1.

Q3Header provides the clicked(), pressed() and released() signals. If the user changes the size of a section, the sizeChange() signal is emitted. If you want to have a sizeChange() signal emitted continuously whilst the user is resizing (rather than just after the resizing is finished), use setTracking(). If the user moves a section the indexChange() signal is emitted.

See also Q3ListView and Q3Table.

Property Documentation

 // Allow resizing of all current and future sections
 header->setResizeEnabled(true);
 // Disable resizing of section 3, (the fourth section added)
 header->setResizeEnabled(false, 3);