[Qt] QT binding anomalies

[zeljko]

On Friday 05 March 2010 09:35, Juha Manninen wrote:
> > Cursor problem wasn't visible to me since my XOrg is 6.8.2 and I have
> > pretty fast machine.
>
> Fast machine didn't help there because the cursor stayed invisible until I
> moved it. Did you finally reproduce it or could you fix it without seeing
> the problem? I am still wondering...

I've fixed it without seeing the problem :)


> > Just try to create pure qt pascal app (without LCL) , using qt45.pas
> > only, so you'll see imediatelly does it flicks or not. Maybe I don't see
> > flickering because my machine is too fast.
>
> Where do I put the QT combobox if there is no LCL form? There must be some
> container, right?

Here is example how to create non LCL app (I don't know if it works, I've used 
it to test some things some time ago, probably you have to change hooks 
because this is pretty old example).

program testforjuha;
{$mode objfpc}{$H+}
uses
  {$IFDEF UNIX}
  cthreads,
  clocale,
  cwstring,
  {$ENDIF}
  Classes,
  SysUtils,
  { you can add units after this }
  qt4;


type TApp = class (TObject)

  public
    qApp: QApplicationH;
    qWin: QMainWindowH;
    qPro: QProgressBarH;
    qEdit: QLineEditH;
    qEdit2: QLineEditH;
    qCombo: QComboBoxH;
    FDropList: QListWidgetH;
    qStatus: QStatusBarH;
    qLabel1: QLabelH;
    qLabel2: QLabelH;
    qLabel3: QLabelH;
    qPrn: QPrinterH;
    FAppEvenFilterHook: QObject_hookH;
    FProgresEvenFilterHook: QObject_hookH;
    FComboEventFilterHook: QObject_hookH;
    FEditEventFilterHook: QObject_hookH;
    FSelectHook: QComboBox_hookH;
    FSelectionChangeHook: QListWidget_hookH;
    FItemPressedHook: QListWidget_hookH;
    constructor Create;
    destructor Destroy; override;
    function EventFilter(Sender: QObjectH; Event: QEventH): Boolean; cdecl;
    function ProgresEventFilter(Sender: QObjectH; Event: QEventH): Boolean; 
cdecl;
    procedure SlotSelect(index: Integer); cdecl;
    procedure signalSelectionChanged(); cdecl;
    procedure signalItemActivated(Item: QListWidgetItemH); cdecl;
    function Execute: Integer;
  end;

procedure TApp.SlotSelect(index: Integer); cdecl;
begin
  writeln('Slot select from comboBox ....');
end;

procedure TApp.signalSelectionChanged(); cdecl;
var
  Item: QListWidgetItemH;
  List: QListWidgetH;
  i: Integer;
begin
  WriteLn('QComboBox ListWidget signalSelectionChange');
  List := QListWidgetH(QComboBox_view(qCombo));
  Item := QListWidget_currentItem(List);
  if Item <> nil then
  begin
    writeln('ITEM SELECTED ? ',QListWidgetItem_isSelected(Item));
    i := QListWidget_row(List, Item);
    if QListWidgetItem_isSelected(Item) then
    begin
      QComboBox_setCurrentIndex(qCombo, i);
    end;
    writeln('CHANGED ROW=',i);
  end;
end;

procedure TApp.signalItemActivated(Item: QListWidgetItemH); cdecl;
var
  i: Integer;
  List: QListWidgetH;
begin
  writeln('QListWidget signalItemActivated() ');
  if Item = nil then
  begin
    writeln('******** ITEM IS NIL *********');
    exit;
  end;
  List := QListWidgetH(QComboBox_view(qCombo));
  i := QListWidget_row(List, Item);
  writeln('SignalItemActivated i=',i,' 
Selected? ',QListWidgetItem_isSelected(Item));
end;

constructor TApp.Create;
var
  WStr: WideString;
begin
  inherited Create;
  qPrn := nil;
  qApp := QApplication_create(@argc, argv);
  FAppEvenFilterHook := QObject_hook_create(qApp);
  QObject_hook_hook_events(FAppEvenFilterHook, @EventFilter);
  qWin := QMainWindow_create();
  qStatus := QStatusBar_create();
  WStr := 'Label 1';
  qLabel1 := QLabel_create(@WStr);
  WStr := 'Label 2';
  qLabel2 := QLabel_create(@WStr);
  WStr := 'Label 3';
  qLabel3 := QLabel_create(@WStr);
  QStatusBar_addWidget(qStatus, qLabel1, 0);
  QStatusBar_addWidget(qStatus, qLabel2, 0);
  QStatusBar_addWidget(qStatus, qLabel3, 1);
  QMainWindow_setStatusBar(qWin, qStatus);
  QWidget_resize(qWin, 800, 600);
  qPro := QProgressBar_create(qWin);
  qEdit := QLineEdit_create(qWin);
  qEdit2 := QLineEdit_create(qWin);
  qCombo := QComboBox_create(qWin);
  // QWidget_setMouseTracking(qCombo, True);
  // QWidget_setFocusPolicy(qCombo, QtStrongFocus);
  // QWidget_setAttribute(qCombo, QtWA_MacShowFocusRect, True);
  // QWidget_setAttribute(qCombo, QtWA_KeyboardFocusChange, True);

  FSelectHook := QComboBox_hook_create(qCombo);
  QComboBox_hook_hook_currentIndexChanged(FSelectHook, @SlotSelect);

  FDropList := QListWidget_create();
  QAbstractItemView_setAutoScroll(FDropList, True);
  QComboBox_setModel(qCombo, QAbstractItemView_model(FDropList));
  QComboBox_setView(qCombo, FDropList);

  FSelectionChangeHook := QListWidget_hook_create(FDropList);
  QListWidget_hook_hook_itemSelectionChanged(FSelectionChangeHook, 
@signalSelectionChanged);

  FItemPressedHook := QListWidget_hook_create(FDropList);
  QListWidget_hook_hook_itemActivated(FItemPressedHook, @signalItemActivated);


  FProgresEvenFilterHook := QObject_hook_create(qPro);
  QObject_hook_hook_events(FProgresEvenFilterHook, @ProgresEventFilter);

  FComboEventFilterHook := QObject_hook_create(qCombo);
  QObject_hook_hook_events(FComboEventFilterHook, @ProgresEventFilter);

  FEditEventFilterHook := QObject_hook_create(qEdit2);
  QObject_hook_hook_events(FEditEventFilterHook, @ProgresEventFilter);

  // QComboBox_setEditable(qCombo, True);
  WStr := 'One';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Two';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Three';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Four';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Five';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Six';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Seven';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Eight';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Nine';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Eleven';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Twelve';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Thirteen';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Fourteen';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Fifteen';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Sixteen';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Seventeen';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Eighteen';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Nineteen';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Twenty';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Twenty one';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());
  WStr := 'Twenty two';
  QComboBox_addItem(qCombo, @WStr, QVariant_create());

  // QWidget_setFocusPolicy(qCombo, QtStrongFocus);

  // QWidget_setFocusPolicy(qCombo, QtClickFocus);
  QWidget_setFocusPolicy(qPro, QtNoFocus);
  QWidget_setMouseTracking(qPro, True);

  QWidget_resize(qPro, 500, 30);
  QWidget_move(qPro, 20, 100);
  QProgressBar_setValue(qPro, 40);
  QLineEdit_setFrame(qEdit, False);
  QLineEdit_setFrame(qEdit2, False);
  QWidget_move(qEdit, 20, 160);
  QWidget_move(qEdit2, 200, 160);
  QWidget_setEnabled(qEdit, False);
  //QComboBox_setEditable(qCombo , True);
  QWidget_move(qCombo, 320, 160);

  QWIdget_show(qWin);
  // QWidget_showMaximized(qWin);
end;

destructor TApp.Destroy;
begin
  QListWidget_hook_destroy(FItemPressedHook);
  QListWidget_hook_destroy(FSelectionChangeHook);
  QComboBox_hook_destroy(FSelectHook);
  QObject_hook_destroy(FEditEventFilterHook);
  QObject_hook_destroy(FComboEventFilterHook);
  QObject_hook_destroy(FProgresEvenFilterHook);
  if qPrn <> nil then
    QPrinter_destroy(qPrn);
  inherited Destroy;
end;

function TApp.Execute: Integer;
begin
  Result := QApplication_exec();
end;

function TApp.EventFilter(Sender: QObjectH; Event: QEventH): Boolean; cdecl;
begin
  Result := False;
  QEvent_accept(Event);
  (*
  case QEvent_type(Event) of
    QEventMouseButtonPress: writeln('Mouse press ....');
    QEventMouseButtonRelease: writeln('Mouse release  ....');
    QEventMouseButtonDblClick: writeln('Mouse dbl click ....');
  end;
  *)
end;

function TApp.ProgresEventFilter(Sender: QObjectH; Event: QEventH): Boolean; 
cdecl;
var
  Ev: QKeyEventH;
  Modifiers: QtKeyboardModifiers;
  Text: WideString;
  Key: Integer;
  NKey: Integer;
  KScan: LongWord;
  i: Integer;
  AKey: Char;
  Opt: QStyleOptionComboBoxH;
  AState: QStyleState;
  WTitle: WideString;
  WStr: WideString;
  s: String;
begin
  Result := False;
  QEvent_accept(Event);
  case QEvent_type(Event) of
    QEventFocusIn:
    begin
      writeln('COMBO IS FOCUSED !');
    end;
    QEventMouseButtonPress:
    begin
      // QWidget_setEnabled(qEdit, true);
      // QWidget_update(qEdit);
      writeln('Progres Mouse press ....');
    end;
    QEventMouseButtonRelease: writeln('Progres Mouse release  ....');
    QEventMouseButtonDblClick: writeln('Progres Mouse dbl click ....');
    QEventKeyPress:
    begin
      Ev := QKeyEventH(Event);
      Modifiers := QKeyEvent_modifiers(Ev);
      Key := QKeyEvent_key(Ev);
      QKeyEvent_text(Ev, @Text);
      NKey := QKeyEvent_nativeVirtualKey(Ev);
      KScan := QKeyEvent_nativeScanCode(Ev);
    end;
    QEventKeyRelease:
    begin
    end;
  end;
end;

var
  FApp: TApp;
begin
  FApp := TApp.Create;
  FApp.Execute;
  FApp.Free;
end.