]> git.saurik.com Git - wxWidgets.git/blobdiff - samples/erase/erase.cpp
Don't call wxTextMeasure::BeginMeasuring() when using non-native wxDC.
[wxWidgets.git] / samples / erase / erase.cpp
index 2e93bae7e663889a2d7da5349cc4f77447d56426..eb54c2ede3e43c215d7df50bbf84e7e132dbdb23 100644 (file)
@@ -1,11 +1,11 @@
 /////////////////////////////////////////////////////////////////////////////
-// Name:        erase.cpp
-// Purpose:     Erase wxWindows sample
-// Author:      Robert Roebling
-// Modified by:
+// Name:        samples/erase/erase.cpp
+// Purpose:     Erase wxWidgets sample
+// Author:      Robert Roebling, Vadim Zeitlin
 // Created:     04/01/98
 // RCS-ID:      $Id$
-// Copyright:   (c) Robert Roebling
+// Copyright:   (c) 1998 Robert Roebling
+//              (c) 2009 Vadim Zeitlin
 // Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
 // headers
 // ----------------------------------------------------------------------------
 
-#ifdef __GNUG__
-    #pragma implementation "erase.cpp"
-    #pragma interface "erase.cpp"
-#endif
-
 // For compilers that support precompilation, includes "wx/wx.h".
 #include "wx/wxprec.h"
 
 #endif
 
 // for all others, include the necessary headers (this file is usually all you
-// need because it includes almost all "standard" wxWindows headers)
+// need because it includes almost all "standard" wxWidgets headers)
 #ifndef WX_PRECOMP
     #include "wx/wx.h"
 #endif
 
+#include "wx/custombgwin.h"
+#include "wx/dcbuffer.h"
+#include "wx/artprov.h"
+
 // ----------------------------------------------------------------------------
 // resources
 // ----------------------------------------------------------------------------
+
 // the application icon
-#if defined(__WXGTK__) || defined(__WXMOTIF__) || defined(__WXMAC__)
-    #include "mondrian.xpm"
+#ifndef wxHAS_IMAGES_IN_RESOURCES
+    #include "../sample.xpm"
 #endif
 
 // ----------------------------------------------------------------------------
@@ -54,29 +54,144 @@ public:
 };
 
 
+class MyCanvas : public wxCustomBackgroundWindow<wxScrolledWindow>
+{
+public:
+    MyCanvas(wxFrame *parent);
+
+    void UseBuffer(bool useBuffer) { m_useBuffer = useBuffer; Refresh(); }
+    bool UsesBuffer() const { return m_useBuffer; }
+
+    void UseBgBitmap(bool useBgBmp)
+    {
+        m_useBgBmp = useBgBmp;
+        SetBackgroundBitmap(m_useBgBmp ? GetBgBitmap() : wxBitmap());
+
+        Refresh();
+    }
+
+    void EraseBgInPaint(bool erase) { m_eraseBgInPaint = erase; Refresh(); }
+
+private:
+    void OnPaint( wxPaintEvent &event );
+    void OnEraseBackground( wxEraseEvent &event );
+
+    void DoPaint(wxDC& dc);
+
+    // Create an easily recognizable background bitmap.
+    static wxBitmap GetBgBitmap()
+    {
+        static const int BMP_SIZE = 40;
+
+        wxBitmap bmp(BMP_SIZE, BMP_SIZE);
+        wxMemoryDC dc(bmp);
+        dc.SetBackground(*wxCYAN);
+        dc.Clear();
+
+        dc.SetPen(*wxBLUE_PEN);
+        dc.DrawLine(0, BMP_SIZE/2, BMP_SIZE/2, 0);
+        dc.DrawLine(BMP_SIZE/2, 0, BMP_SIZE, BMP_SIZE/2);
+        dc.DrawLine(BMP_SIZE, BMP_SIZE/2, BMP_SIZE/2, BMP_SIZE);
+        dc.DrawLine(BMP_SIZE/2, BMP_SIZE, 0, BMP_SIZE/2);
+
+        return bmp;
+    }
+
+    wxBitmap    m_bitmap;
+
+    // use wxMemoryDC in OnPaint()?
+    bool m_useBuffer;
+
+    // use background bitmap?
+    bool m_useBgBmp;
+
+    // erase background in OnPaint()?
+    bool m_eraseBgInPaint;
+
+
+    DECLARE_EVENT_TABLE()
+};
+
 class MyFrame : public wxFrame
 {
 public:
-    MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size);
+    MyFrame();
 
+private:
+    void OnUseBuffer(wxCommandEvent& event);
+    void OnUseBgBitmap(wxCommandEvent& event);
+    void OnEraseBgInPaint(wxCommandEvent& event);
+    void OnChangeBgStyle(wxCommandEvent& event);
     void OnQuit(wxCommandEvent& event);
     void OnAbout(wxCommandEvent& event);
 
-private:
+    // we can only use double-buffering with wxBG_STYLE_PAINT
+    void OnUpdateUIUseBuffer(wxUpdateUIEvent& event)
+    {
+        event.Enable( m_canvas->GetBackgroundStyle() == wxBG_STYLE_PAINT );
+    }
+
+    void OnUpdateUIChangeBgStyle(wxUpdateUIEvent& event)
+    {
+        event.Enable( !m_canvas->UsesBuffer() );
+    }
+
+    MyCanvas *m_canvas;
+
     DECLARE_EVENT_TABLE()
 };
 
-
-class MyCanvas : public wxScrolledWindow
+class ControlWithTransparency : public wxWindow
 {
 public:
-    MyCanvas( MyFrame *parent );
-    
-    void OnPaint( wxPaintEvent &event );
-    void OnEraseBackground( wxEraseEvent &event );
+    ControlWithTransparency(wxWindow *parent,
+                            const wxPoint& pos,
+                            const wxSize& size)
+    {
+        wxString reason;
+        if ( parent->IsTransparentBackgroundSupported(&reason) )
+        {
+            SetBackgroundStyle (wxBG_STYLE_TRANSPARENT);
+            m_message = "This is custom control with transparency";
+        }
+        else
+        {
+            m_message = "Transparency not supported, check tooltip.";
+        }
+
+        Create (parent, wxID_ANY, pos, size, wxBORDER_NONE);
+        Connect(wxEVT_PAINT,
+                wxPaintEventHandler(ControlWithTransparency::OnPaint));
+
+        if ( !reason.empty() )
+        {
+            // This can be only done now, after creating the window.
+            SetToolTip(reason);
+        }
+    }
 
 private:
-    DECLARE_EVENT_TABLE()
+    void OnPaint( wxPaintEvent& WXUNUSED(event) )
+    {
+        wxPaintDC dc(this);
+
+        dc.SetPen(*wxRED_PEN);
+        dc.SetBrush(*wxTRANSPARENT_BRUSH);
+        dc.DrawRectangle(GetClientSize());
+
+        dc.SetTextForeground(*wxBLUE);
+        dc.SetBackgroundMode(wxTRANSPARENT);
+        dc.DrawText(m_message, 0, 2);
+
+        // Draw some bitmap/icon to ensure transparent bitmaps are indeed
+        //  transparent on transparent windows
+        wxBitmap bmp(wxArtProvider::GetBitmap(wxART_WARNING, wxART_MENU));
+        wxIcon icon(wxArtProvider::GetIcon(wxART_GOTO_LAST, wxART_MENU));
+        dc.DrawBitmap (bmp, GetSize().x - 1 - bmp.GetWidth(), 2);
+        dc.DrawIcon(icon, GetSize().x - 1 - bmp.GetWidth()-icon.GetWidth(), 2);
+    }
+
+    wxString m_message;
 };
 
 // ----------------------------------------------------------------------------
@@ -86,8 +201,14 @@ private:
 enum
 {
     // menu items
-    Minimal_Quit = 1,
-    Minimal_About
+    Erase_Menu_UseBuffer = 100,
+    Erase_Menu_UseBgBitmap,
+    Erase_Menu_EraseBgInPaint,
+    Erase_Menu_BgStyleErase,
+    Erase_Menu_BgStyleSystem,
+    Erase_Menu_BgStylePaint,
+    Erase_Menu_Exit = wxID_EXIT,
+    Erase_Menu_About = wxID_ABOUT
 };
 
 
@@ -99,12 +220,14 @@ IMPLEMENT_APP(MyApp)
 
 bool MyApp::OnInit()
 {
-    MyFrame *frame = new MyFrame("Minimal wxWindows App",
-                                 wxPoint(50, 50), wxSize(450, 340));
+    if ( !wxApp::OnInit() )
+        return false;
 
-    frame->Show(TRUE);
-    
-    return TRUE;
+    MyFrame *frame = new MyFrame;
+
+    frame->Show(true);
+
+    return true;
 }
 
 // ----------------------------------------------------------------------------
@@ -112,26 +235,46 @@ bool MyApp::OnInit()
 // ----------------------------------------------------------------------------
 
 BEGIN_EVENT_TABLE(MyFrame, wxFrame)
-    EVT_MENU(Minimal_Quit,  MyFrame::OnQuit)
-    EVT_MENU(Minimal_About, MyFrame::OnAbout)
+    EVT_MENU(Erase_Menu_UseBuffer, MyFrame::OnUseBuffer)
+    EVT_MENU(Erase_Menu_UseBgBitmap, MyFrame::OnUseBgBitmap)
+    EVT_MENU(Erase_Menu_EraseBgInPaint, MyFrame::OnEraseBgInPaint)
+    EVT_MENU_RANGE(Erase_Menu_BgStyleErase, Erase_Menu_BgStylePaint,
+                   MyFrame::OnChangeBgStyle)
+
+    EVT_MENU(Erase_Menu_Exit,  MyFrame::OnQuit)
+    EVT_MENU(Erase_Menu_About, MyFrame::OnAbout)
+
+    EVT_UPDATE_UI(Erase_Menu_UseBuffer, MyFrame::OnUpdateUIUseBuffer)
+    EVT_UPDATE_UI_RANGE(Erase_Menu_BgStyleErase, Erase_Menu_BgStylePaint,
+                        MyFrame::OnUpdateUIChangeBgStyle)
 END_EVENT_TABLE()
 
 // frame constructor
-MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
-       : wxFrame((wxFrame *)NULL, -1, title, pos, size)
+MyFrame::MyFrame()
+       : wxFrame(NULL, wxID_ANY, "Erase sample",
+                 wxPoint(50, 50), wxSize(450, 340))
 {
-#ifdef __WXMAC__
-    wxApp::s_macAboutMenuItemId = Minimal_About;
-#endif
-
-    SetIcon(wxICON(mondrian));
+    SetIcon(wxICON(sample));
 
     wxMenu *menuFile = new wxMenu("", wxMENU_TEAROFF);
+    menuFile->AppendCheckItem(Erase_Menu_UseBuffer, "&Use memory DC\tCtrl-M");
+    menuFile->AppendCheckItem(Erase_Menu_UseBgBitmap,
+                              "Use background &bitmap\tCtrl-B");
+    menuFile->AppendCheckItem(Erase_Menu_EraseBgInPaint,
+                              "&Erase background in EVT_PAINT\tCtrl-R");
+    menuFile->AppendSeparator();
+    menuFile->AppendRadioItem(Erase_Menu_BgStyleErase,
+                              "Use wxBG_STYLE_&ERASE\tCtrl-E");
+    menuFile->AppendRadioItem(Erase_Menu_BgStyleSystem,
+                              "Use wxBG_STYLE_&SYSTEM\tCtrl-S");
+    menuFile->AppendRadioItem(Erase_Menu_BgStylePaint,
+                              "Use wxBG_STYLE_&PAINT\tCtrl-P");
+    menuFile->AppendSeparator();
+    menuFile->Append(Erase_Menu_Exit, "E&xit\tAlt-X", "Quit this program");
 
-    wxMenu *helpMenu = new wxMenu;
-    helpMenu->Append(Minimal_About, "&About...\tCtrl-A", "Show about dialog");
 
-    menuFile->Append(Minimal_Quit, "E&xit\tAlt-X", "Quit this program");
+    wxMenu *helpMenu = new wxMenu;
+    helpMenu->Append(Erase_Menu_About, "&About\tCtrl-A", "Show about dialog");
 
     wxMenuBar *menuBar = new wxMenuBar();
     menuBar->Append(menuFile, "&File");
@@ -139,54 +282,161 @@ MyFrame::MyFrame(const wxString& title, const wxPoint& pos, const wxSize& size)
 
     SetMenuBar(menuBar);
 
-#if wxUSE_STATUSBAR
-    // create a status bar just for fun (by default with 1 pane only)
-    CreateStatusBar(2);
-    SetStatusText("Welcome to wxWindows!");
-#endif // wxUSE_STATUSBAR
+    m_canvas = new MyCanvas( this );
+}
+
+
+void MyFrame::OnUseBuffer(wxCommandEvent& event)
+{
+    m_canvas->UseBuffer(event.IsChecked());
+}
 
-    (void)new MyCanvas( this );
+void MyFrame::OnUseBgBitmap(wxCommandEvent& event)
+{
+    m_canvas->UseBgBitmap(event.IsChecked());
 }
 
+void MyFrame::OnEraseBgInPaint(wxCommandEvent& event)
+{
+    m_canvas->EraseBgInPaint(event.IsChecked());
+}
+
+void MyFrame::OnChangeBgStyle(wxCommandEvent& event)
+{
+    int style = wxBG_STYLE_ERASE + event.GetId() - Erase_Menu_BgStyleErase;
+    m_canvas->SetBackgroundStyle(static_cast<wxBackgroundStyle>(style));
+
+    m_canvas->Refresh();
+}
 
 void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event))
 {
-    Close(TRUE);
+    Close(true);
 }
 
 void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event))
 {
-    wxString msg;
-    msg.Printf( _T("This is the about dialog of the Erase sample.\n")
-                _T("Welcome to %s"), wxVERSION_STRING);
-
-    wxMessageBox(msg, "About Erase", wxOK | wxICON_INFORMATION, this);
+    wxMessageBox
+    (
+        "This sample shows differences between different background styles "
+        "and how you may draw custom background.\n"
+        "\n"
+        "(c) 1998 Robert Roebling\n"
+        "(c) 2009 Vadim Zeitlin\n",
+        "About Erase Sample",
+        wxOK | wxICON_INFORMATION,
+        this
+    );
 }
 
 
 BEGIN_EVENT_TABLE(MyCanvas, wxScrolledWindow)
-    EVT_PAINT(  MyCanvas::OnPaint)
-    EVT_ERASE_BACKGROUND(  MyCanvas::OnEraseBackground)
+    EVT_PAINT(MyCanvas::OnPaint)
+    EVT_ERASE_BACKGROUND(MyCanvas::OnEraseBackground)
 END_EVENT_TABLE()
 
-MyCanvas::MyCanvas( MyFrame *parent )
- : wxScrolledWindow( parent, -1, wxDefaultPosition, wxDefaultSize, 
-                    wxScrolledWindowStyle|wxNO_FULL_REPAINT_ON_RESIZE )
+MyCanvas::MyCanvas(wxFrame *parent)
 {
+    Create(parent, wxID_ANY);
+
+    m_useBuffer = false;
+    m_useBgBmp = false;
+    m_eraseBgInPaint = false;
+
     SetScrollbars( 10, 10, 40, 100, 0, 0 );
+
+    m_bitmap = wxBitmap( wxICON(sample) );
+
+    new wxStaticBitmap( this, wxID_ANY, m_bitmap, wxPoint(80,20) );
+
+    new wxStaticText(this, wxID_ANY,
+                     "Left bitmap is a wxStaticBitmap,\n"
+                     "right one drawn directly",
+                     wxPoint(150, 20));
+
+    new ControlWithTransparency(this, wxPoint(65, 125), wxSize(350, 22));
+
+    SetFocusIgnoringChildren();
+    SetBackgroundColour(*wxCYAN);
 }
 
-void MyCanvas::OnPaint( wxPaintEvent &event )
+void MyCanvas::DoPaint(wxDC& dc)
 {
-    wxPaintDC dc(this);
-    PrepareDC( dc );
-    
-    dc.SetBrush( *wxRED_BRUSH );
-    dc.DrawRectangle( 100, 100, 300, 500 );
+    if ( m_eraseBgInPaint )
+    {
+        dc.SetBackground(*wxLIGHT_GREY);
+        dc.Clear();
+
+        dc.DrawText("Background erased in OnPaint", 65, 110);
+    }
+    else if ( GetBackgroundStyle() == wxBG_STYLE_PAINT )
+    {
+        dc.SetTextForeground(*wxRED);
+        dc.DrawText("You must enable erasing background in OnPaint to avoid "
+                    "display corruption", 65, 110);
+    }
+
+    dc.DrawBitmap( m_bitmap, 20, 20, true );
+
+    dc.SetTextForeground(*wxRED);
+    dc.DrawText("This text is drawn from OnPaint", 65, 65);
 }
 
-void MyCanvas::OnEraseBackground( wxEraseEvent &event )
+void MyCanvas::OnPaint( wxPaintEvent &WXUNUSED(event) )
 {
-    event.Skip( TRUE );
+    if ( m_useBuffer )
+    {
+        wxAutoBufferedPaintDC dc(this);
+        PrepareDC(dc);
+
+        DoPaint(dc);
+    }
+    else
+    {
+        wxPaintDC dc(this);
+        PrepareDC(dc);
+
+        DoPaint(dc);
+    }
+}
+
+void MyCanvas::OnEraseBackground( wxEraseEvent& event )
+{
+    // We must not erase the background ourselves if we asked wxPanel to erase
+    // it using a background bitmap.
+    if ( m_useBgBmp )
+    {
+        event.Skip();
+        return;
+    }
+
+    wxASSERT_MSG
+    (
+        GetBackgroundStyle() == wxBG_STYLE_ERASE,
+        "shouldn't be called unless background style is \"erase\""
+    );
+
+    wxDC& dc = *event.GetDC();
+    dc.SetPen(*wxGREEN_PEN);
+
+    PrepareDC( dc );
+
+    // clear any junk currently displayed
+    dc.Clear();
+
+    const wxSize size = GetClientSize();
+    for ( int x = 0; x < size.x; x += 15 )
+    {
+        dc.DrawLine(x, 0, x, size.y);
+    }
+
+    for ( int y = 0; y < size.y; y += 15 )
+    {
+        dc.DrawLine(0, y, size.x, y);
+    }
+
+    dc.SetTextForeground(*wxRED);
+    dc.SetBackgroundMode(wxSOLID);
+    dc.DrawText("This text is drawn from OnEraseBackground", 60, 160);
 }