Qt 4.4.0
I need to create a palette toolbar like CorelDRAW has. It can be expanded to show all the colors and minimized into one column/row. I've tried both ways, using QGridLayout and setting positions and sizes of all widgets manually but nothing works normally
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PaletteToolbarButton.h
Qt Code: 
  1. #ifndef PALETTETOOLBARBUTTON_H
  2. #define PALETTETOOLBARBUTTON_H
  3.  
  4. #include <QFrame>
  5.  
  6. class PaletteToolbarButton : public QFrame
  7. {
  8.     Q_OBJECT
  9. public:
  10.     PaletteToolbarButton(const QColor& newcolor = Qt::white, QWidget *parent = 0, const QSize& size = QSize(20,20), bool select = false);
  11.     QColor color() const
  12.     {
  13.         return curColor;
  14.     }
  15.     bool isSelected() const 
  16.     {
  17.         return selected;
  18.     }
  19. public slots:
  20.     void setColor(const QColor&);
  21.     void setSelected(bool sel = true);
  22. signals:
  23.     void clicked(const QColor&);
  24. protected:  
  25.     void paintEvent ( QPaintEvent * event );
  26.     void mousePressEvent ( QMouseEvent * event );
  27. private:
  28.     QColor curColor;
  29.     bool selected;
  30. };
  31.  
  32. #endif // PALETTETOOLBARBUTTON_H
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PaletteToolbarButton.cpp
Qt Code: 
  1. #include <QtGui>
  2. #include "PaletteToolbarButton.h"
  3.  
  4. PaletteToolbarButton::PaletteToolbarButton(const QColor& newcolor, QWidget *parent, const QSize& size, bool select)
  5.     : QFrame(parent), selected(select)
  6. {
  7.     newcolor.isValid()? curColor = newcolor : curColor = Qt::transparent;
  8.     setMinimumSize(size);
  9.     setMaximumSize(size);
  10. }
  11. void PaletteToolbarButton::setColor(const QColor& newcolor)
  12. {
  13.     if (newcolor.isValid() && newcolor != curColor)
  14.     {
  15.         curColor = newcolor;
  16.         update ();
  17.     }
  18. }
  19. void PaletteToolbarButton::setSelected(bool sel)
  20. {
  21.     selected = sel;
  22.     update();
  23. }
  24. void PaletteToolbarButton::paintEvent ( QPaintEvent * event ) 
  25. {
  26.     if (selected)
  27.          setFrameStyle(QFrame::WinPanel | QFrame::Raised);
  28.     else setFrameStyle(QFrame::WinPanel | QFrame::Sunken);
  29.     QFrame::paintEvent(event);
  30.     QPainter painter(this);
  31.     if (curColor == Qt::transparent)
  32.     {
  33.         painter.setBrush(Qt::white);
  34.         painter.setPen(Qt::black);
  35.         painter.drawRect(1,1,width()-3,height()-3);
  36.         painter.drawLine(1,1,width()-2,height()-2);
  37.         painter.drawLine(1,height()-2,width()-2,1);
  38.     }
  39.     else
  40.     {   
  41.         painter.setBrush(curColor);
  42.         painter.setPen(Qt::NoPen);
  43.         painter.drawRect(2,2,width()-4,height()-4);
  44.     }
  45. }
  46. void PaletteToolbarButton::mousePressEvent ( QMouseEvent * event )
  47. {
  48.     if (event->button() == Qt::LeftButton)
  49.         emit clicked(curColor);
  50. }
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PaletteToolbar.h
Qt Code: 
  1. #ifndef PALETTETOOLBAR_H
  2. #define PALETTETOOLBAR_H
  3.  
  4. #include <QToolBar>
  5. #include "PaletteToolbarButton.h"
  6.  
  8. class PaletteToolbar : public QToolBar
  9. {
  10.     Q_OBJECT
  11. public:
  12.     PaletteToolbar(const QList<QColor>& colorList = QList<QColor>(), const QString& title = "Palette", QWidget* parent = 0);
  13.     void addColor(const QColor&, int before = -1);//-1 means "add after the last one"
  14.     void removeColor(const QColor&);
  15.     bool isExpanded() const
  16.         {return expanded;}
  17.     QColor color() const
  18.         { return selButton->color(); }
  19. public slots:
  20.     void setExpanded(bool);
  21.     void setSelColor(const QColor&);
  22. signals:
  23.     void expands(bool);
  24.     void colorChosen(const QColor&);
  25. private slots:
  26.     void arrangeButtons();
  27.     void expandButtonTriggered();
  28. protected:
  29.     void resizeEvent ( QResizeEvent * event ) ;
  30. private:
  31.     bool expanded;
  32.     bool arranging;
  33.     QList<PaletteToolbarButton*> buttonList;
  34.     PaletteToolbarButton* selButton;
  35.     QWidget* layoutWidget;
  36.     QToolButton* expandButton;
  37.     QToolButton* customizeButton;
  38. };
  39.  
  40. #endif // PALETTETOOLBAR_H
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PaletteToolbar.cpp
Qt Code: 
  1. #include <QtGui>
  2. #include "PaletteToolbar.h"
  3. PaletteToolbar::PaletteToolbar(const QList<QColor>& colorList, const QString& title, QWidget* parent)
  4.     : QToolBar(title,parent), expanded(false), arranging(false)
  5. {
  6.     setFloatable(false);
  7.     layoutWidget = new QWidget(this);
  8.     QAction* actExpand = new QAction(this);
  9.     expandButton = new QToolButton(layoutWidget);
  10.     expandButton->setDefaultAction(actExpand);
  11.     connect(actExpand, SIGNAL(triggered()), this, SLOT(expandButtonTriggered()));
  12.     addWidget(layoutWidget);
  13.     foreach(QColor color, colorList)
  14.     {
  15.         PaletteToolbarButton* newButton = new PaletteToolbarButton(color,layoutWidget);
  16.         buttonList.append(newButton);
  17.         connect(newButton,SIGNAL(clicked(const QColor&)),this,SLOT(setSelColor(const QColor&)));
  18.     }
  19.     expandButton->setMinimumSize(buttonList.first()->minimumSize());
  20.     expandButton->setMaximumSize(buttonList.first()->maximumSize());
  21.     if (buttonList.size()) selButton = buttonList.first();
  22. }
  23. void PaletteToolbar::addColor(const QColor&, int before)
  24. {}
  25. void PaletteToolbar::removeColor(const QColor&)
  26. {}
  27. void PaletteToolbar::setExpanded(bool newexp)
  28. {
  29.     if (expanded != newexp)
  30.     {
  31.         expanded = newexp;
  32.         arrangeButtons();
  33.         emit expands(newexp);
  34.     }
  35. }
  36. void PaletteToolbar::setSelColor(const QColor& newcolor)
  37. {
  38.     selButton->setSelected(false);
  39.     selButton = static_cast<PaletteToolbarButton*> (sender());
  40.     selButton->setSelected(true);
  41.     emit colorChosen(newcolor);
  42. }
  43. void PaletteToolbar::resizeEvent ( QResizeEvent * event ) 
  44. {
  45.     QToolBar::resizeEvent(event);
  46.     if (!arranging) 
  47.         arrangeButtons();
  48. }
  49. void PaletteToolbar::expandButtonTriggered()
  50. {
  51.     if (expanded)
  52.         setExpanded(false);
  53.     else setExpanded(true);
  54. }
  55. void PaletteToolbar::arrangeButtons()
  56. {
  57.     if (buttonList.size()!=0)
  58.     {
  59.         arranging = true;
  60.         delete layoutWidget->layout();
  61.         QGridLayout* grid = new QGridLayout;
  62.         grid->setSpacing(2);
  63.         int cellWidth = buttonList.first()->minimumWidth()+2;
  64.         int cellHeight = buttonList.first()->minimumHeight()+2;
  65.         bool vert = orientation()==Qt::Vertical;
  66.         switch(static_cast<QMainWindow*>(parentWidget())->toolBarArea(this))
  67.         {
  68.         case Qt::LeftToolBarArea:
  69.             expandButton->setArrowType(expanded? Qt::LeftArrow : Qt::RightArrow);
  70.             break;
  71.         case Qt::RightToolBarArea:
  72.             expandButton->setArrowType(expanded? Qt::RightArrow : Qt::LeftArrow);
  73.             break;
  74.         case Qt::BottomToolBarArea:
  75.             expandButton->setArrowType(expanded? Qt::DownArrow : Qt::UpArrow);
  76.             break;
  77.         case Qt::TopToolBarArea:
  78.             expandButton->setArrowType(expanded? Qt::UpArrow : Qt::DownArrow);
  79.             break;
  80.         }
  81.         int ButtonsInRow,ButtonsInCol;
  82.         if (!expanded)
  83.         {
  84.             if (vert)
  85.             {
  86.                 ButtonsInRow = 1;
  87.                 ButtonsInCol = height() / cellHeight;
  88.             }
  89.             else //horizontal
  90.             {
  91.                 ButtonsInCol = 1;
  92.                 ButtonsInRow = width() / cellWidth;
  93.             }
  94.         }
  95.         else //ToolBar is expanded
  96.         {
  97.             if (vert)
  98.             {
  99.                 ButtonsInCol = height() / cellHeight;
  100.                 ButtonsInRow = (buttonList.size() + 1) / ButtonsInCol;
  101.                 if ((buttonList.size() + 1) % ButtonsInCol) ++ButtonsInRow;
  102.             }
  103.             else //horizontal
  104.             {
  105.                 ButtonsInRow = width() / cellWidth;
  106.                 ButtonsInCol = (buttonList.size() + 1) / ButtonsInRow;
  107.                 if ((buttonList.size() + 1) % ButtonsInRow) ++ButtonsInCol;
  108.             }
  109.         }
  110.         int Row = 0,Col = 0,i=0;
  111.         foreach(PaletteToolbarButton* button,buttonList)
  112.         {
  113.             grid->addWidget(button,Row,Col);++i;
  114.             if (vert)
  115.             {
  116.                 ++Row;
  117.                 if (Row >= ButtonsInCol - 1) 
  118.                 {
  119.                     if (Col >= ButtonsInRow - 1) 
  120.                     {
  121.                         break; 
  122.                     }
  123.                     else
  124.                     {
  125.                         ++Col;
  126.                         Row = 0;
  127.                     }
  128.                 }
  129.             }
  130.             else //horizontal
  131.             {
  132.                 ++Col;
  133.                 if (Col >= ButtonsInRow - 1)
  134.                 {   
  135.                     if (Row >= ButtonsInCol - 1) 
  136.                     {
  137.                         break;
  138.                     }
  139.                     else 
  140.                     {
  141.                         ++Row;
  142.                         Col = 0;
  143.                     }
  144.                 }
  145.             }
  146.         }//foreach
  147.         grid->addWidget(expandButton,Row,Col);
  148.         layoutWidget->setLayout(grid);
  149.         arranging = false;
  150.     }//if (buttonList.size()!=0)
  151. }
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in the constructor of the class derived from QMainWindow:
Qt Code: 
  1. QStringList names = QColor::colorNames();
  2.     QList<QColor> colorlist;
  3.     foreach(QString name, names)
  4.     {
  5.         colorlist.append(QColor(name));
  6.     }
  7.     palette = new PaletteToolbar(colorlist);
  8.     addToolBar(Qt::RightToolBarArea,palette);
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thanks in advance!