reset preview bitmap variable to NULL after deleting it

[wxWidgets.git] / samples / caret / caret.cpp

diff --git a/samples/caret/caret.cpp b/samples/caret/caret.cpp
index 2ecaf096a12cea363597d1a02f2c8c3ceec5ef33..760b54a8307d78d02c544b4ce9bdca315e1b78e8 100644 (file)
--- a/samples/caret/caret.cpp
+++ b/samples/caret/caret.cpp
@@ -9,18 +9,6 @@
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 

-// ============================================================================
-// declarations
-// ============================================================================
-
-// ----------------------------------------------------------------------------
-// headers
-// ----------------------------------------------------------------------------
-#ifdef __GNUG__
-    #pragma implementation "caret.cpp"
-    #pragma interface "caret.cpp"
-#endif
-

 // For compilers that support precompilation, includes "wx/wx.h".
 #include <wx/wxprec.h>
 
 // For compilers that support precompilation, includes "wx/wx.h".
 #include <wx/wxprec.h>
 


@@ -63,22 +51,6 @@ public:
     virtual bool OnInit();
 };
 
     virtual bool OnInit();
 };
 

-// Define a new frame type: this is going to be our main frame
-class MyFrame : public wxFrame
-{
-public:
-    // ctor(s)
-    MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size);
-
-    // event handlers (these functions should _not_ be virtual)
-    void OnQuit(wxCommandEvent& event);
-    void OnAbout(wxCommandEvent& event);
-
-private:
-    // any class wishing to process wxWindows events must use this macro
-    DECLARE_EVENT_TABLE()
-};
-

 // MyCanvas is a canvas on which you can type
 class MyCanvas: public wxScrolledWindow
 {
 // MyCanvas is a canvas on which you can type
 class MyCanvas: public wxScrolledWindow
 {


@@ -89,6 +61,10 @@ public:
 
     wxChar& CharAt(int x, int y) { return *(m_text + x + m_xChars * y); }
 
 
     wxChar& CharAt(int x, int y) { return *(m_text + x + m_xChars * y); }
 

+    // operations
+    void CreateCaret();
+    void MoveCaret(int x, int y);
+

     // caret movement
     void Home() { m_xCaret = 0; }
     void End() { m_xCaret = m_xChars - 1; }
     // caret movement
     void Home() { m_xCaret = 0; }
     void End() { m_xCaret = m_xChars - 1; }


@@ -105,6 +81,9 @@ public:
     void OnChar( wxKeyEvent &event );
 
 private:
     void OnChar( wxKeyEvent &event );
 
 private:

+    // move the caret to m_xCaret, m_yCaret
+    void DoMoveCaret();
+

     wxFont   m_font;
 
     // the margin around the text (looks nicer)
     wxFont   m_font;
 
     // the margin around the text (looks nicer)


@@ -126,6 +105,27 @@ private:
     DECLARE_EVENT_TABLE()
 };
 
     DECLARE_EVENT_TABLE()
 };
 

+
+// Define a new frame type: this is going to be our main frame
+class MyFrame : public wxFrame
+{
+public:
+    // ctor(s)
+    MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size);
+
+    // event handlers (these functions should _not_ be virtual)
+    void OnQuit(wxCommandEvent& event);
+    void OnAbout(wxCommandEvent& event);
+    void OnSetBlinkTime(wxCommandEvent& event);
+    void OnCaretMove(wxCommandEvent& event);
+
+private:
+    MyCanvas *m_canvas;
+
+    // any class wishing to process wxWindows events must use this macro
+    DECLARE_EVENT_TABLE()
+};
+

 // ----------------------------------------------------------------------------
 // constants
 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------
 // constants
 // ----------------------------------------------------------------------------


@@ -134,13 +134,13 @@ private:
 enum
 {
     // menu items
 enum
 {
     // menu items

-    Minimal_Quit = 1,
-    Minimal_About,
-    Minimal_Test1,
-    Minimal_Test2,
+    Caret_Quit = 1,
+    Caret_About,
+    Caret_SetBlinkTime,
+    Caret_Move,

 
     // controls start here (the numbers are, of course, arbitrary)
 
     // controls start here (the numbers are, of course, arbitrary)

-    Minimal_Text = 1000,
+    Caret_Text = 1000

 };
 
 // ----------------------------------------------------------------------------
 };
 
 // ----------------------------------------------------------------------------


@@ -151,8 +151,10 @@ enum
 // handlers) which process them. It can be also done at run-time, but for the
 // simple menu events like this the static method is much simpler.
 BEGIN_EVENT_TABLE(MyFrame, wxFrame)
 // handlers) which process them. It can be also done at run-time, but for the
 // simple menu events like this the static method is much simpler.
 BEGIN_EVENT_TABLE(MyFrame, wxFrame)

-    EVT_MENU(Minimal_Quit,  MyFrame::OnQuit)
-    EVT_MENU(Minimal_About, MyFrame::OnAbout)
+    EVT_MENU(Caret_Quit,  MyFrame::OnQuit)
+    EVT_MENU(Caret_About, MyFrame::OnAbout)
+    EVT_MENU(Caret_SetBlinkTime, MyFrame::OnSetBlinkTime)
+    EVT_MENU(Caret_Move, MyFrame::OnCaretMove)

 END_EVENT_TABLE()
 
 // Create a new application object: this macro will allow wxWindows to create
 END_EVENT_TABLE()
 
 // Create a new application object: this macro will allow wxWindows to create


@@ -173,14 +175,11 @@ IMPLEMENT_APP(MyApp)
 // `Main program' equivalent: the program execution "starts" here
 bool MyApp::OnInit()
 {
 // `Main program' equivalent: the program execution "starts" here
 bool MyApp::OnInit()
 {

-    // Create the main application window
-    MyFrame *frame = new MyFrame("Minimal wxWindows App",
+    // create and show the main application window
+    MyFrame *frame = new MyFrame("Caret wxWindows sample",

                                  wxPoint(50, 50), wxSize(450, 340));
 
                                  wxPoint(50, 50), wxSize(450, 340));
 

-    // Show it and tell the application that it's our main window
-    // @@@ what does it do exactly, in fact? is it necessary here?

     frame->Show(TRUE);
     frame->Show(TRUE);

-    SetTopWindow(frame);

 
     // success: wxApp::OnRun() will be called which will enter the main message
     // loop and the application will run. If we returned FALSE here, the
 
     // success: wxApp::OnRun() will be called which will enter the main message
     // loop and the application will run. If we returned FALSE here, the


@@ -202,9 +201,12 @@ MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
     // create a menu bar
     wxMenu *menuFile = new wxMenu;
 
     // create a menu bar
     wxMenu *menuFile = new wxMenu;
 

-    menuFile->Append(Minimal_About, "&About...\tCtrl-A", "Show about dialog");
+    menuFile->Append(Caret_SetBlinkTime, "&Blink time...\tCtrl-B");
+    menuFile->Append(Caret_Move, "&Move caret\tCtrl-C");

     menuFile->AppendSeparator();
     menuFile->AppendSeparator();

-    menuFile->Append(Minimal_Quit, "E&xit\tAlt-X", "Quit this program");
+    menuFile->Append(Caret_About, "&About...\tCtrl-A", "Show about dialog");
+    menuFile->AppendSeparator();
+    menuFile->Append(Caret_Quit, "E&xit\tAlt-X", "Quit this program");

 
     // now append the freshly created menu to the menu bar...
     wxMenuBar *menuBar = new wxMenuBar;
 
     // now append the freshly created menu to the menu bar...
     wxMenuBar *menuBar = new wxMenuBar;


@@ -213,7 +215,7 @@ MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
     // ... and attach this menu bar to the frame
     SetMenuBar(menuBar);
     
     // ... and attach this menu bar to the frame
     SetMenuBar(menuBar);
     

-    (void) new MyCanvas( this );
+    m_canvas = new MyCanvas(this);

 
     // create a status bar just for fun (by default with 1 pane only)
     CreateStatusBar(2);
 
     // create a status bar just for fun (by default with 1 pane only)
     CreateStatusBar(2);


@@ -231,21 +233,32 @@ void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event))
 
 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
 {
 
 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
 {

-    wxString msg;
-    msg.Printf( _T("This is the about dialog of minimal sample.\n")
-                _T("Welcome to %s")
-#ifdef wxBETA_NUMBER
-               _T(" (beta %d)!")
-#endif // wxBETA_NUMBER
-               , wxVERSION_STRING
-#ifdef wxBETA_NUMBER
-               , wxBETA_NUMBER
-#endif // wxBETA_NUMBER
-              );
-
-    wxMessageBox(msg, "About Minimal", wxOK | wxICON_INFORMATION, this);
+    wxMessageBox(_T("The caret wxWindows sample.\n© 1999 Vadim Zeitlin"),
+                 _T("About Caret"), wxOK | wxICON_INFORMATION, this);

 }
 
 }
 

+void MyFrame::OnCaretMove(wxCommandEvent& WXUNUSED(event))
+{
+    m_canvas->MoveCaret(10, 10);
+}
+
+void MyFrame::OnSetBlinkTime(wxCommandEvent& WXUNUSED(event))
+{
+    long blinkTime = wxGetNumberFromUser
+                     (
+                      _T("The caret blink time is the time between two blinks"),
+                      _T("Time in milliseconds:"),
+                      _T("wxCaret sample"),
+                      wxCaret::GetBlinkTime(), 0, 10000,
+                      this
+                     );
+    if ( blinkTime != -1 )
+    {
+        wxCaret::SetBlinkTime((int)blinkTime);
+        m_canvas->CreateCaret();
+        wxLogStatus(this, _T("Blink time set to %ld milliseconds."), blinkTime);
+    }
+}

 
 // ----------------------------------------------------------------------------
 // MyCanvas
 
 // ----------------------------------------------------------------------------
 // MyCanvas


@@ -266,29 +279,52 @@ MyCanvas::MyCanvas( wxWindow *parent )
 {
     m_text = (wxChar *)NULL;
 
 {
     m_text = (wxChar *)NULL;
 

-    SetBackgroundColour(* wxWHITE);
+    SetBackgroundColour(*wxWHITE);
+
+    m_font = wxFont(12, wxFONTFAMILY_TELETYPE,
+                    wxFONTSTYLE_NORMAL, wxFONTWEIGHT_NORMAL);
+
+    m_xCaret = m_yCaret =
+    m_xChars = m_yChars = 0;
+
+    m_xMargin = m_yMargin = 5;

 
 

-    m_font = *wxNORMAL_FONT;
+    CreateCaret();
+}

 
 

+MyCanvas::~MyCanvas()
+{
+    free(m_text);
+}
+
+void MyCanvas::CreateCaret()
+{

     wxClientDC dc(this);
     wxClientDC dc(this);

-    dc.SetFont( m_font );
+    dc.SetFont(m_font);

     m_heightChar = dc.GetCharHeight();
     m_widthChar = dc.GetCharWidth();
 
     wxCaret *caret = new wxCaret(this, m_widthChar, m_heightChar);
     SetCaret(caret);
 
     m_heightChar = dc.GetCharHeight();
     m_widthChar = dc.GetCharWidth();
 
     wxCaret *caret = new wxCaret(this, m_widthChar, m_heightChar);
     SetCaret(caret);
 

-    m_xCaret = m_yCaret =
-    m_xChars = m_yChars = 0;
-
-    m_xMargin = m_yMargin = 5;

     caret->Move(m_xMargin, m_yMargin);
     caret->Show();
 }
 
     caret->Move(m_xMargin, m_yMargin);
     caret->Show();
 }
 

-MyCanvas::~MyCanvas()
+void MyCanvas::MoveCaret(int x, int y)

 {
 {

-    free(m_text);
+    m_xCaret = x;
+    m_yCaret = y;
+
+    DoMoveCaret();
+}
+
+void MyCanvas::DoMoveCaret()
+{
+    wxLogStatus(_T("Caret is at (%d, %d)"), m_xCaret, m_yCaret);
+
+    GetCaret()->Move(m_xMargin + m_xCaret * m_widthChar,
+                     m_yMargin + m_yCaret * m_heightChar);

 }
 
 void MyCanvas::OnSize( wxSizeEvent &event )
 }
 
 void MyCanvas::OnSize( wxSizeEvent &event )


@@ -316,10 +352,16 @@ void MyCanvas::OnSize( wxSizeEvent &event )
     event.Skip();
 }
 
     event.Skip();
 }
 

+// NB: this method is horrible inefficient especially because the caret
+//     needs to be redrawn often and in this case we only have to redraw
+//     the caret location and not the entire window - in a real program we
+//     would use GetUpdateRegion() and iterate over rectangles it contains

 void MyCanvas::OnPaint( wxPaintEvent &WXUNUSED(event) )
 {
 void MyCanvas::OnPaint( wxPaintEvent &WXUNUSED(event) )
 {

+    wxCaretSuspend cs(this);

     wxPaintDC dc( this );
     PrepareDC( dc );
     wxPaintDC dc( this );
     PrepareDC( dc );

+    dc.Clear();

 
     dc.SetFont( m_font );
 
 
     dc.SetFont( m_font );
 


@@ -373,23 +415,26 @@ void MyCanvas::OnChar( wxKeyEvent &event )
             break;
 
         default:
             break;
 
         default:

-            if ( wxIsprint(event.KeyCode()) )
+            if ( !event.AltDown() && wxIsprint(event.KeyCode()) )

             {
             {

-                CharAt(m_xCaret, m_yCaret) = (wxChar)event.KeyCode();
+                wxChar ch = (wxChar)event.KeyCode();
+                CharAt(m_xCaret, m_yCaret) = ch;
+
+                wxCaretSuspend cs(this);
+                wxClientDC dc(this);
+                dc.SetFont(m_font);
+                dc.SetBackgroundMode(wxSOLID); // overwrite old value
+                dc.DrawText(ch, m_xMargin + m_xCaret * m_widthChar,
+                                m_yMargin + m_yCaret * m_heightChar );
+

                 NextChar();
             }
             else
             {
                 NextChar();
             }
             else
             {

-                // don't refresh
-                return;
+                event.Skip();

             }
     }
 
             }
     }
 

-    wxLogStatus(_T("Caret is at (%d, %d)"), m_xCaret, m_yCaret);
-
-    GetCaret()->Move(m_xMargin + m_xCaret * m_widthChar,
-                     m_yMargin + m_yCaret * m_heightChar);
-
-    Refresh();
+    DoMoveCaret();

 }
 
 }