Class derived from Fl_Button with added help blobs

Source/FLTKDialog/FLTKPropertyNameButtonWithHelp.cxx

@@ -0,0 +1,160 @@
+#include <FLTKPropertyNameButtonWithHelp.h>
+#include <Fl/Fl.H>
+
+namespace fltk {
+  
+Fl_Window *   PropertyNameButtonWithHelp::helpBlob = 0;
+Fl_Box    *   PropertyNameButtonWithHelp::helpText = 0;
+unsigned int  PropertyNameButtonWithHelp::counter  = 0;
+int           PropertyNameButtonWithHelp::lastMousePositionX = 0;
+int           PropertyNameButtonWithHelp::lastMousePositionY = 0;
+ 
+
+
+PropertyNameButtonWithHelp
+::PropertyNameButtonWithHelp(int x,int y, int w, int h, const char * l):
+Fl_Button(x,y,w,h,l) 
+{
+  counter++;    // one more object instantiated 
+}
+
+
+
+
+PropertyNameButtonWithHelp::
+~PropertyNameButtonWithHelp( )
+{
+  counter--;
+  if( counter == 0 )
+  {
+    delete helpBlob;
+    delete helpText;
+  }
+}
+
+
+
+void
+PropertyNameButtonWithHelp
+::SetHelpText( const char * text )
+{
+  m_HelpText = text;
+}
+
+
+
+void
+PropertyNameButtonWithHelp
+::ShowHelp( void )
+{
+  if( helpBlob )
+  {
+    helpBlob->show();
+  }
+}
+ 
+
+void
+PropertyNameButtonWithHelp
+::HideHelp( void )
+{
+  if( helpBlob )
+  {
+    helpBlob->hide();
+  }
+}
+
+
+
+
+int 
+PropertyNameButtonWithHelp::
+handle( int event )
+{
+
+  const float delayForShowingHelpBlob = 1.0; // seconds
+  
+  const int   maxWidth   = 300;
+  const int   lineHeight =  20;
+
+
+  // Create the help blob window if it doesn't exist
+  if( !helpBlob )
+  {
+    helpBlob = new Fl_Window(0,0,200,20,"");
+    helpBlob->border( 0 );
+    helpText = new Fl_Box(0,0,200,20,"");
+    helpBlob->end();
+    Fl_Color yellowHelp = FL_YELLOW;
+    helpBlob->color( yellowHelp );
+    helpText->color( yellowHelp );
+    helpText->align( FL_ALIGN_CENTER | FL_ALIGN_INSIDE | FL_ALIGN_WRAP );
+  }
+ 
+  int eventManaged = 0;
+  
+  switch( event )
+  {
+    case FL_ENTER: 
+     {
+      lastMousePositionX = Fl::event_x();
+      lastMousePositionY = Fl::event_y();
+      const float factor = helpText->labelsize() * 0.5;
+      int height = lineHeight;
+      int area   = (int)( m_HelpText.size() * factor );
+      int width  = area;
+      if( width > maxWidth )
+      {
+        width  = maxWidth;
+        height = area / maxWidth * lineHeight;
+        if( area % maxWidth != 0 ) 
+        {
+          height += lineHeight;
+        }
+      }
+      helpText->size( width, height );
+      helpBlob->size( width, height );
+      helpText->label(  m_HelpText.c_str() );
+      Fl_Widget * parent = this->parent();
+      Fl::add_timeout( delayForShowingHelpBlob, ShowHelpBlobCallback, (void *)parent );
+      eventManaged = 0;
+      break;
+      }
+    case FL_LEAVE:
+      helpBlob->hide();
+      eventManaged = 0;
+      break;
+    case FL_MOVE:
+      helpBlob->hide();
+      eventManaged = 0;
+      break;
+    default:
+      eventManaged = 0;
+  }
+  
+
+  return eventManaged;
+
+}
+
+void 
+PropertyNameButtonWithHelp::
+ShowHelpBlobCallback( void * data )   
+{
+
+  Fl_Widget * thisWidget  = Fl::belowmouse();
+  Fl_Widget * eventWidget = (Fl_Widget *)data;
+
+  if( thisWidget == eventWidget )
+  {
+
+    helpBlob->position( lastMousePositionX, lastMousePositionY );
+    helpBlob->show();
+  }
+
+}
+
+
+
+
+} // end namespace fltk

Source/FLTKDialog/FLTKPropertyNameButtonWithHelp.h

@@ -0,0 +1,51 @@
+#ifndef  FLTKPropertyNameButtonWithHelp_h
+#define  FLTKPropertyNameButtonWithHelp_h
+
+#include <Fl/Fl_Tile.H>
+#include <Fl/Fl_Input.H>
+#include <Fl/Fl_Box.H>
+#include <Fl/Fl_Button.H>
+#include <Fl/Fl_Window.H>
+#include <string>
+
+namespace fltk {
+  
+
+/**
+  
+  Helper class for managing  help blobs over the property name
+
+  */
+class PropertyNameButtonWithHelp : public Fl_Button
+{
+  public:
+    PropertyNameButtonWithHelp(int x,int y,int w, int h,const char *l);
+    virtual ~PropertyNameButtonWithHelp();
+    int handle(int event);
+    void SetHelpText( const char * helpText);
+    void ShowHelp(void);
+    void HideHelp(void);
+    
+    static void ShowHelpBlobCallback( void * );
+
+  private:
+    
+    string                m_HelpText;
+
+    // Class variables
+    static Fl_Window   *  helpBlob;
+    static Fl_Box      *  helpText;
+    static unsigned int   counter;
+    static int            lastMousePositionX;
+    static int            lastMousePositionY;
+
+};
+
+
+
+
+} // end namespace fltk
+
+#endif
+
+