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class TQtWidget: public QWidget

  TQtWidget is a QWidget with the QPixmap double buffer
  It is designed to back the ROOT TCanvasImp class interface  and it can be used
  as a regular Qt Widget to create Qt-based GUI with the embedded TCanvas objects

           This widget can be used as a Qt "custom widget"
         to build a custom GUI interfaces with  Qt Designer

 The class emits the Qt signals and has Qt public slots

  Public slots:  (Qt)

   virtual void cd();  // make the associated TCanvas the current one (shortcut to TCanvas::cd())
   virtual void cd(int subpadnumber); // as above - shortcut to Canvas::cd(int subpadnumber)
   void Disconnect(); // disconnect the QWidget from the ROOT TCanvas (used in the class dtor)
   void Refresh();    // force the associated TCanvas::Update to be called
   virtual bool Save(const QString &fileName) const;  // Save the widget image with some ppixmap file
   virtual bool Save(const char    *fileName) const;
   virtual bool Save(const QString &fileName,const char *format,int quality=60) const;
   virtual bool Save(const char    *fileName,const char *format,int quality=60) const;

  signals        (Qt)

    CanvasPainted();  // Signal the TCanvas has been painted onto the screen
    Saved(bool ok);   // Signal the TCanvas has been saved into the file
    RootEventProcessed(TObject *selected, unsigned int event, TCanvas *c);
                      // Signal the Qt mouse/keyboard event has been process by ROOT
                      // This "signal" is emitted by the enabled mouse events only.
                      // See: EnableSignalEvents
                      // ---  DisableSignalEvents

  public methods:
    The methods below define whether the TQtWidget object emits "RootEventProcessed" Qt signals
     (By default no  RootEventProcessed Qt signal is emitted )
     void EnableSignalEvents (UInt_t f)
     void DisableSignalEvents(UInt_t f),
         where f is a bitwise OR of the mouse event flags:
                  kMousePressEvent       // TCanvas processed QEvent mousePressEvent
                  kMouseMoveEvent        // TCanvas processed QEvent mouseMoveEvent
                  kMouseReleaseEvent     // TCanvas processed QEvent mouseReleaseEvent
                  kMouseDoubleClickEvent // TCanvas processed QEvent mouseDoubleClickEvent
                  kKeyPressEvent         // TCanvas processed QEvent keyPressEvent
                  kEnterEvent            // TCanvas processed QEvent enterEvent
                  kLeaveEvent            // TCanvas processed QEvent leaveEvent

  For example to create the custom responce to the mouse crossing TCanvas
  connect the RootEventProsecced signal with your qt slot:

 connect(tQtWidget,SIGNAL(RootEventProcessed(TObject *, unsigned int, TCanvas *))
          ,this,SLOT(CanvasEvent(TObject *, unsigned int, TCanvas *)));
  . . .

void qtrootexample1::CanvasEvent(TObject *obj, unsigned int event, TCanvas *)
  TQtWidget *tipped = (TQtWidget *)sender();
  const char *objectInfo =
  QString tipText ="You have ";
  if  (tipped == tQtWidget1)
     tipText +="clicked";
     tipText +="passed";
  tipText += " the object <";
  tipText += obj->GetName();
  tipText += "> of class ";
  tipText += obj->ClassName();
  tipText += " : ";
  tipText += objectInfo;


Function Members (Methods)

TQtWidget(QWidget* parent = 0)
static TCanvas*Canvas(TQtWidget* widget)
static TQtWidget*Canvas(const TCanvas* canvas)
static TQtWidget*Canvas(Int_t id)
virtual voidcd()
virtual voidcd(int subpadnumber)
static TClass*Class()
voidDisableSignalEvents(UInt_t f)
voidEmitSignal(UInt_t f)
voidEnableSignalEvents(UInt_t f)
virtual voidErase()
UInt_tGetAllBits() const
const TQtWidgetBuffer*GetBuffer() const
TCanvas*GetCanvas() const
Int_tGetEvent() const
Int_tGetEventX() const
Int_tGetEventY() const
QPixmap*GetOffScreenBuffer() const
TObject*GetSelected() const
TVirtualPad*GetSelectedPad() const
Int_tGetSelectedX() const
Int_tGetSelectedY() const
static TApplication*InitRint(Bool_t prompt = kFALSE, const char* appClassName = "QtRint", int* argc = 0, char** argv = 0, void* options = 0, int numOptions = 0, Bool_t noLogo = kTRUE)
voidInvertBit(UInt_t f)
virtual TClass*IsA() const
boolIsDoubleBuffered() const
Bool_tIsSignalEventEnabled(UInt_t f) const
virtual QSizeminimumSizeHint() const
voidResetBit(UInt_t f)
virtual boolSave(const QString& fileName) const
virtual boolSave(const char* fileName) const
virtual boolSave(const QString& fileName, const char* format, int quality = 60) const
virtual boolSave(const char* fileName, const char* format, int quality = 60) const
voidSetAllBits(UInt_t f)
voidSetBit(UInt_t f)
voidSetBit(UInt_t f, Bool_t set)
voidSetCanvas(TCanvas* c)
voidSetDoubleBuffer(bool on = TRUE)
virtual voidSetSaveFormat(const char* format)
virtual voidShowMembers(TMemberInspector& insp, char* parent)
virtual QSizesizeHint() const
virtual QSizePolicysizePolicy() const
virtual voidStreamer(TBuffer& b)
voidStreamerNVirtual(TBuffer& b)
Bool_tTestBit(UInt_t f) const
Int_tTestBits(UInt_t f) const
virtual voidcontextMenuEvent(QContextMenuEvent*)
virtual voidcustomEvent(QCustomEvent*)
virtual voidEmitCanvasPainted()
virtual voidenterEvent(QEvent*)
virtual voidexitSizeEvent()
virtual voidfocusInEvent(QFocusEvent*)
virtual voidfocusOutEvent(QFocusEvent*)
QWidget*GetRootID() const
virtual voidkeyPressEvent(QKeyEvent*)
virtual voidkeyReleaseEvent(QKeyEvent*)
virtual voidleaveEvent(QEvent*)
virtual voidmouseDoubleClickEvent(QMouseEvent*)
virtual voidmouseMoveEvent(QMouseEvent*)
virtual voidmousePressEvent(QMouseEvent*)
virtual voidmouseReleaseEvent(QMouseEvent*)
virtual voidpaintEvent(QPaintEvent*)
boolpaintFlag(bool mode = TRUE)
boolPaintingActive() const
virtual voidresizeEvent(QResizeEvent*)
voidSetIgnoreLeaveEnter(int ignore = 1)
voidSetRootID(QWidget* wrapper)
virtual voidSetSizeHint(const QSize& size)
virtual voidshowEvent(QShowEvent*)
virtual voidstretchWidget(QResizeEvent* e)
TQtWidget(const TQtWidget&)
voidoperator=(const TQtWidget&)

Data Members

enum { kBitMask
TQtWidgetBuffer*fPixmapIDDouble buffer of this widget
TQtWidgetBuffer*fPixmapScreenDouble buffer for no-double buffer operation
UInt_tfBitsbit field status word

Class Charts

Inheritance Inherited Members Includes Libraries
Class Charts

Function documentation

TQtWidget(QWidget* mother, const char* name, Qt::WFlags f,bool embedded)
TQtWidget(QWidget* mother, Qt::WFlags f,bool embedded)
{ setObjectName("tqtwidget"); Init() ;}
void Init()
void AdjustBufferSize()
 Adjust the widget buffer size
TCanvas * Canvas()
 Alias for GetCanvas method
TCanvas * Canvas(TQtWidget *widget)
 static: return TCanvas by TQtWidget pointer
TQtWidget * Canvas(const TCanvas *canvas)
 static: return the TQtWidget backend for TCanvas *canvas object
TQtWidget * Canvas(Int_t id)
 static: return TQtWidget by TCanvas id
TApplication * InitRint(Bool_t prompt = kFALSE, const char* appClassName = "QtRint", int* argc = 0, char** argv = 0, void* options = 0, int numOptions = 0, Bool_t noLogo = kTRUE)
 Instantiate ROOT from within Qt application if needed
 Return the TRint pointer
 Most parametrs are passed to TRint class ctor

 Bool_t prompt = kTRUE;  Instantiate ROOT with ROOT command prompt
                 kFALSE; No ROOT prompt. The default for Qt GUI applications

  The prompt option can be defined via ROOT parameter file ".rootrc"
    . . .
  Gui.Prompt   yes

void Erase()
 Erases the entire widget and its double buffer
void cd()
 [slot] to make this embedded canvas the current one
void cd(int subpadnumber)
 [slot] to make this embedded canvas / pad the current one
void Disconnect()
 [slot] Disconnect the Qt widget from TCanvas object before deleting
 to avoid the dead lock
 one has to set CanvasID = 0 to disconnect things properly.
void Refresh()
 [slot]  to allow Qt signal refreshing the ROOT TCanvas if needed
void SetCanvas(TCanvas* c)
  remember my host TCanvas and adopt its name
customEvent(QCustomEvent* )
 The custom response to the special WIN32 events
 These events are not present with X11 systems
void contextMenuEvent(QContextMenuEvent* )
 The custom response to the Qt QContextMenuEvent
 Map QContextMenuEvent to the ROOT kButton3Down = 3  event
void focusInEvent(QFocusEvent* )
 The custom response to the Qt QFocusEvent "in"
 this imposes an extra protection to avoid TObject interaction with
 mouse event accidently
void focusOutEvent(QFocusEvent* )
 The custom response to the Qt QFocusEvent "out"
 this imposes an extra protection to avoid TObject interaction with
 mouse event accidently
void mousePressEvent(QMouseEvent* )
 Map the Qt mouse press button event to the ROOT TCanvas events
 Mouse events occur when a mouse button is pressed or released inside
 a widget or when the mouse cursor is moved.
void mouseMoveEvent(QMouseEvent* )
  Map the Qt mouse move pointer event to the ROOT TCanvas events
  kMouseMotion   = 51,
  kButton1Motion = 21, kButton2Motion = 22, kButton3Motion = 23, kKeyPress = 24
void mouseReleaseEvent(QMouseEvent* )
  Map the Qt mouse button release event to the ROOT TCanvas events
   kButton1Up     = 11, kButton2Up     = 12, kButton3Up     = 13
void mouseDoubleClickEvent(QMouseEvent* )
  Map the Qt mouse double click button event to the ROOT TCanvas events
  kButton1Double = 61, kButton2Double = 62, kButton3Double = 63
void keyPressEvent(QKeyEvent* )
 Map the Qt key press event to the ROOT TCanvas events
 kKeyDown  =  4
void keyReleaseEvent(QKeyEvent* )
 Map the Qt key release event to the ROOT TCanvas events
 kKeyUp    = 14
void enterEvent(QEvent* )
 Map the Qt mouse enters widget event to the ROOT TCanvas events
 kMouseEnter    = 52
void leaveEvent(QEvent* )
  Map the Qt mouse leaves widget event to the ROOT TCanvas events
 kMouseLeave    = 53
void resizeEvent(QResizeEvent* )
 The widget will be erased and receive a paint event immediately after
 processing the resize event.
 No drawing need be (or should be) done inside this handler.
void SetSaveFormat(const char* format)
 Set the default save format for the widget
bool Save(const char *fileName)
  TQtWidget::Save(const QString &fileName) is a public Qt slot.
  it saves the double buffer of this object using the default save
  format  defined the file extension
  If the "fileName" has no extension the "default" format is to be used instead
  The deafult format is "PNG".
  It can be changed with the TQtWidget::SetSaveFormat method

bool Save(const QString &fileName)
  TQtWidget::Save(const QString &fileName) is a public Qt slot.
  it saves the double buffer of this object using the default save
  format  defined the file extension
  If the "fileName" has no extension the "default" format is to be used instead
  The deafult format is "PNG".
  It can be changed with the TQtWidget::SetSaveFormat method

bool Save(const char *fileName,const char *format,int quality)
bool Save(const QString &fileName,const char *format,int quality)
  TQtWidget::save is a public Qt slot.
  it saves the double buffer of this object using QPixmap facility
void SetDoubleBuffer(bool on = TRUE)
 Set the double buffered mode on/off
void stretchWidget(QResizeEvent* e)
 Stretch the widget during sizing
void exitSizeEvent()
 Response to the "exit size event"
bool paintFlag(bool mode = TRUE)
  Set new fPaint flag
  Returns: the previous version of the flag
void showEvent(QShowEvent* )
 Custom handler of the Qt show event
 Non-spontaneous show events are sent to widgets immediately before
 they are shown.
 The spontaneous show events of top-level widgets are delivered afterwards.
void paintEvent(QPaintEvent* )
 Custom handler of the Qt paint event
 A paint event is a request to repaint all or part of the widget.
 It can happen as a result of repaint() or update(), or because the widget
 was obscured and has now been uncovered, or for many other reasons.
void SetSizeHint(const QSize& size)
  sets the preferred size of the widget.
QSize sizeHint() const
  returns the preferred size of the widget.
QSize minimumSizeHint() const
 returns the smallest size the widget can have.
QSizePolicy sizePolicy() const
  returns a QSizePolicy; a value describing the space requirements
void EmitTestedSignal()
void SetBit(UInt_t f, Bool_t set)
 Set or unset the user status bits as specified in f.
TQtWidgetBuffer & SetBuffer()
 Create (if needed) and return the buffer
QPixmap * GetOffScreenBuffer() const
  return the current widget buffer;
TCanvas * GetCanvas() const
{ return fCanvas; }
const TQtWidgetBuffer * GetBuffer() const
bool PaintingActive() const
void SetRootID(QWidget* wrapper)
{ fWrapper = wrapper;}
QWidget * GetRootID() const
{ return fWrapper;}
Int_t GetEvent() const

  Proxy methods to access the TCanvas selected TObject
  and last processed event

{ return GetCanvas()->GetEvent(); }
Int_t GetEventX() const
{ return GetCanvas()->GetEventX(); }
Int_t GetEventY() const
{ return GetCanvas()->GetEventY(); }
TObject * GetSelected() const
{ return GetCanvas()->GetSelected(); }
Int_t GetSelectedX() const
{ return GetCanvas()->GetSelectedX(); }
Int_t GetSelectedY() const
{ return GetCanvas()->GetSelectedY(); }
TVirtualPad * GetSelectedPad() const
{ return GetCanvas()->GetSelectedPad(); }
UInt_t GetAllBits() const
----- bit manipulation
{ return fBits; }
void SetAllBits(UInt_t f)
{ fBits = f; }
void SetBit(UInt_t f)
{ fBits |= f & kBitMask; }
void ResetBit(UInt_t f)
{ fBits &= ~(f & kBitMask); }
Bool_t TestBit(UInt_t f) const
{ return (Bool_t) ((fBits & f) != 0); }
Int_t TestBits(UInt_t f) const
{ return (Int_t) (fBits & f); }
void InvertBit(UInt_t f)
{ fBits ^= f & kBitMask; }
void EnableSignalEvents(UInt_t f)
{ SetBit (f); }
void DisableSignalEvents(UInt_t f)
{ ResetBit(f); }
Bool_t IsSignalEventEnabled(UInt_t f) const
{ return TestBit (f); }
void EmitSignal(UInt_t f)
void SetIgnoreLeaveEnter(int ignore = 1)
{ fIgnoreLeaveEnter = ignore; }
void operator=(const TQtWidget& )
----- Private bits, clients can only test but not change them
void ResetCanvas()
{ fCanvas = 0;}
bool IsDoubleBuffered() const
{ return fDoubleBufferOn; }
void EmitCanvasPainted()
{ emit CanvasPainted(); }