I have some more inputs. It looks like a problem of base class QMainWindow. For the same code, Qt3 and Qt4 behaves in a different manner.

Qt3:
- beheaves like native windows apps. QStatusBar::addPermanentWidget really makes the widget permamanent. The user can not resize the main window in a way so that the permanent widgets are hidden.

qt3.PNG

Qt4:
- On resizing certain texts of the supposed-to-permamnent-widget becomes hidden.

qt4.PNG

It's not recommneded to go back to Qt3. So, I need to find out how to take care of this issue in Qt4.

I'm using the portedcanvas Qt example to single out this problem. I added a private method createStatusBar() in canvas.cpp:

Qt Code: 
  1. void Main::createStatusBar()
  2. {
  3. 	statusLabel = new QLabel(tr("Ready"));
  4. 	gridSpacingLabel = new QLabel(tr(" Grid Spacing:  20"));
  5. 	xPosLabel = new QLabel(tr(" X: 640 "));
  6. 	yPosLabel = new QLabel(tr(" Y: 640 "));
  7. 	widthLabel = new QLabel(tr(" Width: 640 "));
  8. 	heightLabel = new QLabel(tr(" Height: 480 "));
  9. 	unsavedDataLabel = new QLabel();
  10. 	QPixmap pixmap(":changes.png");
  11. 	unsavedDataLabel->setPixmap(pixmap);
  12.  
  13. 	statusBar()->addPermanentWidget(gridSpacingLabel);
  14. 	statusBar()->addPermanentWidget(xPosLabel);
  15. 	statusBar()->addPermanentWidget(yPosLabel);
  16. 	statusBar()->addPermanentWidget(widthLabel);
  17. 	statusBar()->addPermanentWidget(heightLabel);
  18. 	statusBar()->addPermanentWidget(unsavedDataLabel);
  19.  
  20. 	statusBar()->addWidget(statusLabel);
  21. 	statusBar()->showMessage(tr("Showing Message"));
  22. }
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This method is called at the end of constructor. Also note the small code change to switch between Qt3 and Qt4 [ Q"3"MainWindow(parent,name,f) ]

Qt Code: 
  1. Main::Main(QGraphicsScene& c, QWidget* parent, const char* name, Qt::WindowFlags f) :
  2.     Q3MainWindow(parent,name,f),
  3. 	//QMainWindow(parent,name,f),
  4.     canvas(c)
  5. {
  6.     editor = new FigureEditor(canvas,this);
  7.     QMenuBar* menu = menuBar();
  8.  
  9.     Q3PopupMenu* file = new Q3PopupMenu( menu );
  10.     file->insertItem("&Fill canvas", this, SLOT(init()), Qt::CTRL+Qt::Key_F);
  11.     file->insertItem("&Erase canvas", this, SLOT(clear()), Qt::CTRL+Qt::Key_E);
  12.     file->insertItem("&New view", this, SLOT(newView()), Qt::CTRL+Qt::Key_N);
  13.     file->insertSeparator();
  14.     file->insertItem("&Print...", this, SLOT(print()), Qt::CTRL+Qt::Key_P);
  15.     file->insertSeparator();
  16.     file->insertItem("E&xit", qApp, SLOT(quit()), Qt::CTRL+Qt::Key_Q);
  17.     menu->insertItem("&File", file);
  18.  
  19.     Q3PopupMenu* edit = new Q3PopupMenu( menu );
  20.     edit->insertItem("Add &Circle", this, SLOT(addCircle()), Qt::ALT+Qt::Key_C);
  21.     edit->insertItem("Add &Hexagon", this, SLOT(addHexagon()), Qt::ALT+Qt::Key_H);
  22.     edit->insertItem("Add &Polygon", this, SLOT(addPolygon()), Qt::ALT+Qt::Key_P);
  23.     edit->insertItem("Add Spl&ine", this, SLOT(addSpline()), Qt::ALT+Qt::Key_I);
  24.     edit->insertItem("Add &Text", this, SLOT(addText()), Qt::ALT+Qt::Key_T);
  25.     edit->insertItem("Add &Line", this, SLOT(addLine()), Qt::ALT+Qt::Key_L);
  26.     edit->insertItem("Add &Rectangle", this, SLOT(addRectangle()), Qt::ALT+Qt::Key_R);
  27.     edit->insertItem("Add &Sprite", this, SLOT(addSprite()), Qt::ALT+Qt::Key_S);
  28.     edit->insertItem("Create &Mesh", this, SLOT(addMesh()), Qt::ALT+Qt::Key_M );
  29.     edit->insertItem("Add &Alpha-blended image", this, SLOT(addButterfly()), Qt::ALT+Qt::Key_A);
  30.     menu->insertItem("&Edit", edit);
  31.  
  32.     Q3PopupMenu* view = new Q3PopupMenu( menu );
  33.     view->insertItem("&Enlarge", this, SLOT(enlarge()), Qt::SHIFT+Qt::CTRL+Qt::Key_Plus);
  34.     view->insertItem("Shr&ink", this, SLOT(shrink()), Qt::SHIFT+Qt::CTRL+Qt::Key_Minus);
  35.     view->insertSeparator();
  36.     view->insertItem("&Rotate clockwise", this, SLOT(rotateClockwise()), Qt::CTRL+Qt::Key_PageDown);
  37.     view->insertItem("Rotate &counterclockwise", this, SLOT(rotateCounterClockwise()), Qt::CTRL+Qt::Key_PageUp);
  38.     view->insertItem("&Zoom in", this, SLOT(zoomIn()), Qt::CTRL+Qt::Key_Plus);
  39.     view->insertItem("Zoom &out", this, SLOT(zoomOut()), Qt::CTRL+Qt::Key_Minus);
  40.     view->insertItem("Translate left", this, SLOT(moveL()), Qt::CTRL+Qt::Key_Left);
  41.     view->insertItem("Translate right", this, SLOT(moveR()), Qt::CTRL+Qt::Key_Right);
  42.     view->insertItem("Translate up", this, SLOT(moveU()), Qt::CTRL+Qt::Key_Up);
  43.     view->insertItem("Translate down", this, SLOT(moveD()), Qt::CTRL+Qt::Key_Down);
  44.     view->insertItem("&Mirror", this, SLOT(mirror()), Qt::CTRL+Qt::Key_Home);
  45.     menu->insertItem("&View", view);
  46.  
  47.     menu->insertSeparator();
  48.  
  49.     Q3PopupMenu* help = new Q3PopupMenu( menu );
  50.     help->insertItem("&About", this, SLOT(help()), Qt::Key_F1);
  51.     help->setItemChecked(dbf_id, TRUE);
  52.     menu->insertItem("&Help",help);
  53.  
  54.     createStatusBar();
  55.  
  56.     setCentralWidget(editor);
  57.  
  58.     printer = 0;
  59.  
  60.     init();
  61. }
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Anyone else? any other idea?

Regards,
Anirban