<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/examples/listboxcombo/listboxcombo.doc:4 --> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Listboxes and Comboboxes</title> <style type="text/css"><!-- fn { margin-left: 1cm; text-indent: -1cm; } a:link { color: #004faf; text-decoration: none } a:visited { color: #672967; text-decoration: none } body { background: #ffffff; color: black; } --></style> </head> <body> <table border="0" cellpadding="0" cellspacing="0" width="100%"> <tr bgcolor="#E5E5E5"> <td valign=center> <a href="index.html"> <font color="#004faf">Home</font></a> | <a href="classes.html"> <font color="#004faf">All Classes</font></a> | <a href="mainclasses.html"> <font color="#004faf">Main Classes</font></a> | <a href="annotated.html"> <font color="#004faf">Annotated</font></a> | <a href="groups.html"> <font color="#004faf">Grouped Classes</font></a> | <a href="functions.html"> <font color="#004faf">Functions</font></a> </td> <td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>Listboxes and Comboboxes</h1> <p> This example program demonstrates how to use listboxes (with single selection and multi selection) and comboboxes (editable and non-editable). <p> <hr> <p> Header file: <p> <pre>/**************************************************************************** ** $Id: qt/listboxcombo.h 3.3.8 edited Jan 11 14:37 $ ** ** Copyright (C) 1992-2007 Trolltech ASA. All rights reserved. ** ** This file is part of an example program for Qt. This example ** program may be used, distributed and modified without limitation. ** *****************************************************************************/ #ifndef LISTBOX_COMBO_H #define LISTBOX_COMBO_H #include <<a href="qvbox-h.html">qvbox.h</a>> class QListBox; class QLabel; class ListBoxCombo : public <a href="qvbox.html">QVBox</a> { <a href="metaobjects.html#Q_OBJECT">Q_OBJECT</a> public: ListBoxCombo( <a href="qwidget.html">QWidget</a> *parent = 0, const char *name = 0 ); protected: <a href="qlistbox.html">QListBox</a> *lb1, *lb2; <a href="qlabel.html">QLabel</a> *label1, *label2; protected slots: void slotLeft2Right(); void slotCombo1Activated( const <a href="qstring.html">QString</a> &s ); void slotCombo2Activated( const <a href="qstring.html">QString</a> &s ); }; #endif </pre> <p> <hr> <p> Implementation: <p> <pre>/**************************************************************************** ** $Id: qt/listboxcombo.cpp 3.3.8 edited Jan 11 14:37 $ ** ** Copyright (C) 1992-2007 Trolltech ASA. All rights reserved. ** ** This file is part of an example program for Qt. This example ** program may be used, distributed and modified without limitation. ** *****************************************************************************/ #include "listboxcombo.h" #include <<a href="qcombobox-h.html">qcombobox.h</a>> #include <<a href="qlistbox-h.html">qlistbox.h</a>> #include <<a href="qhbox-h.html">qhbox.h</a>> #include <<a href="qpushbutton-h.html">qpushbutton.h</a>> #include <<a href="qstring-h.html">qstring.h</a>> #include <<a href="qpixmap-h.html">qpixmap.h</a>> #include <<a href="qlabel-h.html">qlabel.h</a>> #include <<a href="qimage-h.html">qimage.h</a>> #include <<a href="qpainter-h.html">qpainter.h</a>> #include <<a href="qstyle-h.html">qstyle.h</a>> class MyListBoxItem : public <a href="qlistboxitem.html">QListBoxItem</a> { public: MyListBoxItem() : <a href="qlistboxitem.html">QListBoxItem</a>() { setCustomHighlighting( TRUE ); } protected: virtual void paint( <a href="qpainter.html">QPainter</a> * ); virtual int width( const <a href="qlistbox.html">QListBox</a>* ) const { return 100; } virtual int height( const <a href="qlistbox.html">QListBox</a>* ) const { return 16; } }; <a name="x1410"></a>void MyListBoxItem::<a href="qlistboxitem.html#paint">paint</a>( <a href="qpainter.html">QPainter</a> *painter ) { // evil trick: find out whether we are painted onto our listbox <a name="x1413"></a> bool in_list_box = <a href="qlistboxitem.html#listBox">listBox</a>() && listBox()->viewport() == painter-><a href="qpainter.html#device">device</a>(); <a href="qrect.html">QRect</a> r ( 0, 0, width( <a href="qlistboxitem.html#listBox">listBox</a>() ), height( <a href="qlistboxitem.html#listBox">listBox</a>() ) ); if ( in_list_box && isSelected() ) <a name="x1414"></a> painter-><a href="qpainter.html#eraseRect">eraseRect</a>( r ); <a name="x1415"></a> painter-><a href="qpainter.html#fillRect">fillRect</a>( 5, 5, width( listBox() ) - 10, height( listBox() ) - 10, Qt::red ); if ( in_list_box && isCurrent() ) listBox()->style().drawPrimitive( QStyle::PE_FocusRect, painter, r, listBox()->colorGroup() ); } /* * Constructor * * Creates child widgets of the ListBoxCombo widget */ <a name="f437"></a>ListBoxCombo::ListBoxCombo( <a href="qwidget.html">QWidget</a> *parent, const char *name ) : <a href="qvbox.html">QVBox</a>( parent, name ) { <a href="qframe.html#setMargin">setMargin</a>( 5 ); <a href="qhbox.html#setSpacing">setSpacing</a>( 5 ); unsigned int i; <a href="qstring.html">QString</a> str; <a href="qhbox.html">QHBox</a> *row1 = new <a href="qhbox.html">QHBox</a>( this ); <a name="x1402"></a> row1-><a href="qhbox.html#setSpacing">setSpacing</a>( 5 ); // Create a multi-selection ListBox... lb1 = new <a href="qlistbox.html">QListBox</a>( row1 ); <a name="x1408"></a> lb1-><a href="qlistbox.html#setSelectionMode">setSelectionMode</a>( QListBox::Multi ); // ...insert a pixmap item... <a name="x1406"></a> lb1-><a href="qlistbox.html#insertItem">insertItem</a>( QPixmap( "qtlogo.png" ) ); // ...and 100 text items for ( i = 0; i < 100; i++ ) { str = QString( "Listbox Item %1" ).arg( i ); if ( !( i % 4 ) ) lb1-><a href="qlistbox.html#insertItem">insertItem</a>( QPixmap( "fileopen.xpm" ), str ); else lb1-><a href="qlistbox.html#insertItem">insertItem</a>( str ); } // Create a pushbutton... <a href="qpushbutton.html">QPushButton</a> *arrow1 = new <a href="qpushbutton.html">QPushButton</a>( " -> ", row1 ); // ...and connect the clicked SIGNAL with the SLOT slotLeft2Right <a href="qobject.html#connect">connect</a>( arrow1, SIGNAL( <a href="qbutton.html#clicked">clicked</a>() ), this, SLOT( slotLeft2Right() ) ); // create an empty single-selection ListBox lb2 = new <a href="qlistbox.html">QListBox</a>( row1 ); <a href="qhbox.html">QHBox</a> *row2 = new <a href="qhbox.html">QHBox</a>( this ); row2-><a href="qhbox.html#setSpacing">setSpacing</a>( 5 ); <a href="qvbox.html">QVBox</a> *box1 = new <a href="qvbox.html">QVBox</a>( row2 ); box1-><a href="qhbox.html#setSpacing">setSpacing</a>( 5 ); // Create a non-editable Combobox and a label below... <a href="qcombobox.html">QComboBox</a> *cb1 = new <a href="qcombobox.html">QComboBox</a>( FALSE, box1 ); label1 = new <a href="qlabel.html">QLabel</a>( "Current Item: Combobox Item 0", box1 ); <a name="x1416"></a><a name="x1404"></a> label1-><a href="qwidget.html#setMaximumHeight">setMaximumHeight</a>( label1-><a href="qwidget.html#sizeHint">sizeHint</a>().height() * 2 ); <a name="x1401"></a> label1-><a href="qframe.html#setFrameStyle">setFrameStyle</a>( QFrame::Panel | QFrame::Sunken ); //...and insert 50 items into the Combobox for ( i = 0; i < 50; i++ ) { str = QString( "Combobox Item %1" ).arg( i ); if ( i % 9 ) <a name="x1399"></a> cb1-><a href="qcombobox.html#insertItem">insertItem</a>( str ); else <a name="x1400"></a> cb1-><a href="qcombobox.html#listBox">listBox</a>()->insertItem( new MyListBoxItem ); } <a href="qvbox.html">QVBox</a> *box2 = new <a href="qvbox.html">QVBox</a>( row2 ); box2-><a href="qhbox.html#setSpacing">setSpacing</a>( 5 ); // Create an editable Combobox and a label below... <a href="qcombobox.html">QComboBox</a> *cb2 = new <a href="qcombobox.html">QComboBox</a>( TRUE, box2 ); label2 = new <a href="qlabel.html">QLabel</a>( "Current Item: Combobox Item 0", box2 ); label2-><a href="qwidget.html#setMaximumHeight">setMaximumHeight</a>( label2-><a href="qwidget.html#sizeHint">sizeHint</a>().height() * 2 ); label2-><a href="qframe.html#setFrameStyle">setFrameStyle</a>( QFrame::Panel | QFrame::Sunken ); // ... and insert 50 items into the Combobox for ( i = 0; i < 50; i++ ) { str = QString( "Combobox Item %1" ).arg( i ); if ( !( i % 4 ) ) cb2-><a href="qcombobox.html#insertItem">insertItem</a>( QPixmap( "fileopen.xpm" ), str ); else cb2-><a href="qcombobox.html#insertItem">insertItem</a>( str ); } // Connect the activated SIGNALs of the Comboboxes with SLOTs <a name="x1398"></a> <a href="qobject.html#connect">connect</a>( cb1, SIGNAL( <a href="qcombobox.html#activated">activated</a>( const <a href="qstring.html">QString</a> & ) ), this, SLOT( slotCombo1Activated( const <a href="qstring.html">QString</a> & ) ) ); <a href="qobject.html#connect">connect</a>( cb2, SIGNAL( <a href="qcombobox.html#activated">activated</a>( const <a href="qstring.html">QString</a> & ) ), this, SLOT( slotCombo2Activated( const <a href="qstring.html">QString</a> & ) ) ); } /* * SLOT slotLeft2Right * * Copies all selected items of the first ListBox into the * second ListBox */ void <a name="f438"></a>ListBoxCombo::slotLeft2Right() { // Go through all items of the first ListBox <a name="x1405"></a> for ( unsigned int i = 0; i < lb1-><a href="qlistbox.html#count">count</a>(); i++ ) { <a name="x1407"></a> <a href="qlistboxitem.html">QListBoxItem</a> *item = lb1-><a href="qlistbox.html#item">item</a>( i ); // if the item is selected... <a name="x1409"></a> if ( item-><a href="qlistboxitem.html#isSelected">isSelected</a>() ) { // ...and it is a text item... <a name="x1412"></a><a name="x1411"></a> if ( item-><a href="qlistboxitem.html#pixmap">pixmap</a>() && !item-><a href="qlistboxitem.html#text">text</a>().isEmpty() ) lb2-><a href="qlistbox.html#insertItem">insertItem</a>( *item-><a href="qlistboxitem.html#pixmap">pixmap</a>(), item-><a href="qlistboxitem.html#text">text</a>() ); else if ( !item-><a href="qlistboxitem.html#pixmap">pixmap</a>() ) lb2-><a href="qlistbox.html#insertItem">insertItem</a>( item-><a href="qlistboxitem.html#text">text</a>() ); else if ( item-><a href="qlistboxitem.html#text">text</a>().isEmpty() ) lb2-><a href="qlistbox.html#insertItem">insertItem</a>( *item-><a href="qlistboxitem.html#pixmap">pixmap</a>() ); } } } /* * SLOT slotCombo1Activated( const <a href="qstring.html">QString</a> &s ) * * Sets the text of the item which the user just selected * in the first Combobox (and is now the value of s) to * the first Label. */ void <a name="f439"></a>ListBoxCombo::slotCombo1Activated( const <a href="qstring.html">QString</a> &s ) { <a name="x1403"></a> label1-><a href="qlabel.html#setText">setText</a>( QString( "Current Item: %1" ).arg( s ) ); } /* * SLOT slotCombo2Activated( const <a href="qstring.html">QString</a> &s ) * * Sets the text of the item which the user just selected * in the second Combobox (and is now the value of s) to * the second Label. */ void <a name="f440"></a>ListBoxCombo::slotCombo2Activated( const <a href="qstring.html">QString</a> &s ) { label2-><a href="qlabel.html#setText">setText</a>( QString( "Current Item: %1" ).arg( s ) ); } </pre> <p> <hr> <p> Main: <p> <pre>/**************************************************************************** ** $Id: qt/main.cpp 3.3.8 edited Jan 11 14:37 $ ** ** Copyright (C) 1992-2007 Trolltech ASA. All rights reserved. ** ** This file is part of an example program for Qt. This example ** program may be used, distributed and modified without limitation. ** *****************************************************************************/ #include "listboxcombo.h" #include <<a href="qapplication-h.html">qapplication.h</a>> int main( int argc, char **argv ) { <a href="qapplication.html">QApplication</a> a( argc, argv ); ListBoxCombo listboxcombo; listboxcombo.<a href="qwidget.html#resize">resize</a>( 400, 270 ); listboxcombo.<a href="qwidget.html#setCaption">setCaption</a>( "Qt Example - Listboxes and Comboboxes" ); a.<a href="qapplication.html#setMainWidget">setMainWidget</a>( &listboxcombo ); listboxcombo.<a href="qwidget.html#show">show</a>(); return a.<a href="qapplication.html#exec">exec</a>(); } </pre> <p>See also <a href="examples.html">Examples</a>. <!-- eof --> <p><address><hr><div align=center> <table width=100% cellspacing=0 border=0><tr> <td>Copyright © 2007 <a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a> <td align=right><div align=right>Qt 3.3.8</div> </table></div></address></body> </html>