]> git.saurik.com Git - wxWidgets.git/blobdiff - src/gtk1/clipbrd.cpp
finding papersizes allows for 1 mm tolerance
[wxWidgets.git] / src / gtk1 / clipbrd.cpp
index 1304b0ddf1d282afbbead3a9155e58501b568bbe..251709b69ec780c2ef8c1ad0e80bb500be79bac9 100644 (file)
@@ -1,10 +1,10 @@
 /////////////////////////////////////////////////////////////////////////////
-// Name:        clipbrd.cpp
+// Name:        gtk/clipbrd.cpp
 // Purpose:
 // Author:      Robert Roebling
 // Id:          $Id$
 // Copyright:   (c) 1998 Robert Roebling
-// Licence:    wxWindows licence
+// Licence:     wxWindows licence
 /////////////////////////////////////////////////////////////////////////////
 
 #ifdef __GNUG__
 #include "wx/utils.h"
 #include "wx/log.h"
 
-#include "glib.h"
-#include "gdk/gdk.h"
-#include "gtk/gtk.h"
+#include <glib.h>
+#include <gdk/gdk.h>
+#include <gtk/gtk.h>
 
 //-----------------------------------------------------------------------------
 // thread system
 //-----------------------------------------------------------------------------
 
 #if wxUSE_THREADS
-extern void wxapp_install_thread_wakeup();
-extern void wxapp_uninstall_thread_wakeup();
 #endif
 
 //-----------------------------------------------------------------------------
 // data
 //-----------------------------------------------------------------------------
 
-wxClipboard *wxTheClipboard = (wxClipboard*) NULL;
-
 GdkAtom  g_clipboardAtom   = 0;
 GdkAtom  g_targetsAtom     = 0;
 
+// the trace mask we use with wxLogTrace() - call
+// wxLog::AddTraceMask(TRACE_CLIPBOARD) to enable the trace messages from here
+// (there will be a *lot* of them!)
+static const wxChar *TRACE_CLIPBOARD = _T("clipboard");
+
 //-----------------------------------------------------------------------------
 // reminder
 //-----------------------------------------------------------------------------
 
 /* The contents of a selection are returned in a GtkSelectionData
-   structure. selection/target identify the request. 
+   structure. selection/target identify the request.
    type specifies the type of the return; if length < 0, and
    the data should be ignored. This structure has object semantics -
    no fields should be modified directly, they should not be created
@@ -59,9 +60,9 @@ struct _GtkSelectionData
   GdkAtom selection;
   GdkAtom target;
   GdkAtom type;
-  gint   format;
+  gint    format;
   guchar *data;
-  gint   length;
+  gint    length;
 };
 
 */
@@ -71,71 +72,77 @@ struct _GtkSelectionData
 //-----------------------------------------------------------------------------
 
 static void
-targets_selection_received( GtkWidget *WXUNUSED(widget), 
-                            GtkSelectionData *selection_data, 
-#if (GTK_MINOR_VERSION > 0)
+targets_selection_received( GtkWidget *WXUNUSED(widget),
+                            GtkSelectionData *selection_data,
                             guint32 WXUNUSED(time),
-#endif
-                           wxClipboard *clipboard )
+                            wxClipboard *clipboard )
 {
-    if (!wxTheClipboard)
+    if ( wxTheClipboard && selection_data->length > 0 )
     {
-        clipboard->m_waiting = FALSE;
-        return;
-    }
-  
-    if (selection_data->length <= 0)
-    {
-        clipboard->m_waiting = FALSE;
-        return;
-    }
-    
-    /* make sure we got the data in the correct form */
-    if (selection_data->type != GDK_SELECTION_TYPE_ATOM)
-    {
-        clipboard->m_waiting = FALSE;
-        return;
-    }
-  
-    // the atoms we received, holding a list of targets (= formats) 
-    GdkAtom *atoms = (GdkAtom *)selection_data->data;
+        // make sure we got the data in the correct form
+        GdkAtom type = selection_data->type;
+        if ( type != GDK_SELECTION_TYPE_ATOM )
+        {
+            if ( strcmp(gdk_atom_name(type), "TARGETS") )
+            {
+                wxLogTrace( TRACE_CLIPBOARD,
+                            _T("got unsupported clipboard target") );
 
-    for (unsigned int i=0; i<selection_data->length/sizeof(GdkAtom); i++)
-    {
-/*
-        char *name = gdk_atom_name (atoms[i]);
-        if (name) printf( "Format available: %s.\n", name ); */
-      
-        if (atoms[i] == clipboard->m_targetRequested)
+                clipboard->m_waiting = FALSE;
+                return;
+            }
+        }
+
+#ifdef __WXDEBUG__
+        wxDataFormat clip( selection_data->selection );
+        wxLogTrace( TRACE_CLIPBOARD,
+                    wxT("selection received for targets, clipboard %s"),
+                    clip.GetId().c_str() );
+#endif // __WXDEBUG__
+
+        // the atoms we received, holding a list of targets (= formats)
+        GdkAtom *atoms = (GdkAtom *)selection_data->data;
+
+        for (unsigned int i=0; i<selection_data->length/sizeof(GdkAtom); i++)
         {
-            clipboard->m_waiting = FALSE;
-            clipboard->m_formatSupported = TRUE;
-            return;
+            wxDataFormat format( atoms[i] );
+
+            wxLogTrace( TRACE_CLIPBOARD,
+                        wxT("selection received for targets, format %s"),
+                        format.GetId().c_str() );
+
+//            printf( "format %s requested %s\n", 
+//                    gdk_atom_name( atoms[i] ),
+//                    gdk_atom_name( clipboard->m_targetRequested ) );
+
+            if (format == clipboard->m_targetRequested)
+            {
+                clipboard->m_waiting = FALSE;
+                clipboard->m_formatSupported = TRUE;
+                return;
+            }
         }
     }
 
     clipboard->m_waiting = FALSE;
-    return;
 }
 
 //-----------------------------------------------------------------------------
 // "selection_received" for the actual data
 //-----------------------------------------------------------------------------
 
-static void 
-selection_received( GtkWidget *WXUNUSED(widget), 
-                    GtkSelectionData *selection_data, 
-#if (GTK_MINOR_VERSION > 0)
+static void
+selection_received( GtkWidget *WXUNUSED(widget),
+                    GtkSelectionData *selection_data,
                     guint32 WXUNUSED(time),
-#endif
-                   wxClipboard *clipboard )
+                    wxClipboard *clipboard )
 {
     if (!wxTheClipboard)
     {
         clipboard->m_waiting = FALSE;
         return;
     }
-  
+
     wxDataObject *data_object = clipboard->m_receivedData;
 
     if (!data_object)
@@ -143,16 +150,16 @@ selection_received( GtkWidget *WXUNUSED(widget),
         clipboard->m_waiting = FALSE;
         return;
     }
-    
+
     if (selection_data->length <= 0)
     {
         clipboard->m_waiting = FALSE;
         return;
     }
-    
+
     wxDataFormat format( selection_data->target );
-  
-    /* make sure we got the data in the correct format */
+
+    // make sure we got the data in the correct format
     if (!data_object->IsSupportedFormat( format ) )
     {
         clipboard->m_waiting = FALSE;
@@ -161,61 +168,14 @@ selection_received( GtkWidget *WXUNUSED(widget),
 
     /* make sure we got the data in the correct form (selection type).
        if so, copy data to target object */
-    
-    switch (format.GetType())
+    if (selection_data->type != GDK_SELECTION_TYPE_STRING)
     {
-        case wxDF_TEXT:
-       {
-            if (selection_data->type != GDK_SELECTION_TYPE_STRING)
-            {
-                clipboard->m_waiting = FALSE;
-                return;
-            }
-           
-           wxTextDataObject *text_object = (wxTextDataObject *) data_object;
-           
-           wxString text = (const char*) selection_data->data;
-           
-           text_object->SetText( text );
-           
-           break;
-       }
-       
-       case wxDF_BITMAP:
-       {
-            if (selection_data->type != GDK_SELECTION_TYPE_STRING)
-            {
-                clipboard->m_waiting = FALSE;
-                return;
-            }
-           
-           wxBitmapDataObject *bitmap_object = (wxBitmapDataObject *) data_object;
-           
-           bitmap_object->SetData( (size_t) selection_data->length, (const void*) selection_data->data );
-           
-           break;
-       }
-       
-       case wxDF_PRIVATE:
-       {
-            if (selection_data->type != GDK_SELECTION_TYPE_STRING)
-            {
-                clipboard->m_waiting = FALSE;
-                return;
-            }
-           
-           data_object->SetData( format, (size_t) selection_data->length, (const char*) selection_data->data );
-           
-           break;
-       }
-       
-       default:
-       {
-            clipboard->m_waiting = FALSE;
-           return;
-       }
+        clipboard->m_waiting = FALSE;
+        return;
     }
-    
+
+    data_object->SetData( format, (size_t) selection_data->length, (const char*) selection_data->data );
+
     wxTheClipboard->m_formatSupported = TRUE;
     clipboard->m_waiting = FALSE;
 }
@@ -228,7 +188,7 @@ static gint
 selection_clear_clip( GtkWidget *WXUNUSED(widget), GdkEventSelection *event )
 {
     if (!wxTheClipboard) return TRUE;
-    
+
     if (event->selection == GDK_SELECTION_PRIMARY)
     {
         wxTheClipboard->m_ownsPrimarySelection = FALSE;
@@ -243,18 +203,20 @@ selection_clear_clip( GtkWidget *WXUNUSED(widget), GdkEventSelection *event )
         wxTheClipboard->m_waiting = FALSE;
         return FALSE;
     }
-    
+
     if ((!wxTheClipboard->m_ownsPrimarySelection) &&
         (!wxTheClipboard->m_ownsClipboard))
     {
         /* the clipboard is no longer in our hands. we can the delete clipboard data. */
         if (wxTheClipboard->m_data)
-       {
-           delete wxTheClipboard->m_data;
-           wxTheClipboard->m_data = (wxDataObject*) NULL;
-       }
+        {
+            wxLogTrace(TRACE_CLIPBOARD, wxT("wxClipboard will get cleared" ));
+
+            delete wxTheClipboard->m_data;
+            wxTheClipboard->m_data = (wxDataObject*) NULL;
+        }
     }
-  
+
     wxTheClipboard->m_waiting = FALSE;
     return TRUE;
 }
@@ -264,70 +226,39 @@ selection_clear_clip( GtkWidget *WXUNUSED(widget), GdkEventSelection *event )
 //-----------------------------------------------------------------------------
 
 static void
-selection_handler( GtkWidget *WXUNUSED(widget), GtkSelectionData *selection_data, gpointer WXUNUSED(data) )
+selection_handler( GtkWidget *WXUNUSED(widget),
+                   GtkSelectionData *selection_data,
+                   guint WXUNUSED(info),
+                   guint WXUNUSED(time),
+                   gpointer WXUNUSED(data) )
 {
     if (!wxTheClipboard) return;
-  
+
     if (!wxTheClipboard->m_data) return;
-  
+
     wxDataObject *data = wxTheClipboard->m_data;
-    
+
     wxDataFormat format( selection_data->target );
 
     if (!data->IsSupportedFormat( format )) return;
-  
-    if (format.GetType() == wxDF_TEXT)
-    {
-       wxTextDataObject *text_object = (wxTextDataObject*) data;
-       wxString text( text_object->GetText() );
-
-#if wxUSE_UNICODE
-       const wxWX2MBbuf s = text.mbc_str();
-       int len = strlen(s);
-#else // more efficient in non-Unicode
-       const char *s = text.c_str();
-       int len = (int) text.Length();
-#endif
-        gtk_selection_data_set( 
-            selection_data, 
-           GDK_SELECTION_TYPE_STRING, 
-           8*sizeof(gchar),
-           (unsigned char*) (const char*) s,
-            len ); 
-                   
-       return;
-    }
-
-    if (format.GetType() == wxDF_BITMAP)
-    {
-       wxBitmapDataObject *bitmap_object = (wxBitmapDataObject*) data;
-           
-       if (bitmap_object->GetDataSize() == 0) return;
-           
-        gtk_selection_data_set( 
-            selection_data, 
-           GDK_SELECTION_TYPE_STRING, 
-           8*sizeof(gchar), 
-           (unsigned char*) bitmap_object->GetPngData(), 
-           (int) bitmap_object->GetDataSize() );
-           
-       return;
-    }
 
     int size = data->GetDataSize( format );
-    
+
     if (size == 0) return;
-    
-    char *d = new char[size];
-    
-    data->GetDataHere( selection_data->target, (void*) d );
-
-    gtk_selection_data_set( 
-        selection_data, 
-       GDK_SELECTION_TYPE_STRING, 
-       8*sizeof(gchar), 
-       (unsigned char*) d,
-       size ); 
+
+    void *d = malloc(size);
+
+    // Text data will be in UTF8 in Unicode mode.
+    data->GetDataHere( selection_data->target, d );
+
+    gtk_selection_data_set(
+        selection_data,
+        GDK_SELECTION_TYPE_STRING,
+        8*sizeof(gchar),
+        (unsigned char*) d,
+        size );
+
+    free(d);
 }
 
 //-----------------------------------------------------------------------------
@@ -347,43 +278,43 @@ wxClipboard::wxClipboard()
     m_receivedData = (wxDataObject*) NULL;
 
     /* we use m_targetsWidget to query what formats are available */
-    
+
     m_targetsWidget = gtk_window_new( GTK_WINDOW_POPUP );
     gtk_widget_realize( m_targetsWidget );
 
-    gtk_signal_connect( GTK_OBJECT(m_targetsWidget), 
+    gtk_signal_connect( GTK_OBJECT(m_targetsWidget),
                         "selection_received",
-                       GTK_SIGNAL_FUNC( targets_selection_received ), 
-                       (gpointer) this );
-                       
+                        GTK_SIGNAL_FUNC( targets_selection_received ),
+                        (gpointer) this );
+
     /* we use m_clipboardWidget to get and to offer data */
-    
+
     m_clipboardWidget = gtk_window_new( GTK_WINDOW_POPUP );
     gtk_widget_realize( m_clipboardWidget );
 
-    gtk_signal_connect( GTK_OBJECT(m_clipboardWidget), 
+    gtk_signal_connect( GTK_OBJECT(m_clipboardWidget),
                         "selection_received",
-                       GTK_SIGNAL_FUNC( selection_received ), 
-                       (gpointer) this );
+                        GTK_SIGNAL_FUNC( selection_received ),
+                        (gpointer) this );
 
-    gtk_signal_connect( GTK_OBJECT(m_clipboardWidget), 
+    gtk_signal_connect( GTK_OBJECT(m_clipboardWidget),
                         "selection_clear_event",
-                       GTK_SIGNAL_FUNC( selection_clear_clip ), 
-                       (gpointer) NULL );
-                     
+                        GTK_SIGNAL_FUNC( selection_clear_clip ),
+                        (gpointer) NULL );
+
     if (!g_clipboardAtom) g_clipboardAtom = gdk_atom_intern( "CLIPBOARD", FALSE );
     if (!g_targetsAtom) g_targetsAtom = gdk_atom_intern ("TARGETS", FALSE);
-  
+
     m_formatSupported = FALSE;
     m_targetRequested = 0;
-    
+
     m_usePrimary = FALSE;
 }
 
 wxClipboard::~wxClipboard()
 {
-    Clear();  
-  
+    Clear();
+
     if (m_clipboardWidget) gtk_widget_destroy( m_clipboardWidget );
     if (m_targetsWidget) gtk_widget_destroy( m_targetsWidget );
 }
@@ -394,41 +325,41 @@ void wxClipboard::Clear()
     {
 #if wxUSE_THREADS
         /* disable GUI threads */
-        wxapp_uninstall_thread_wakeup();
 #endif
-    
-        /*  As we have data we also own the clipboard. Once we no longer own
-            it, clear_selection is called which will set m_data to zero */
+
+        //  As we have data we also own the clipboard. Once we no longer own
+        //  it, clear_selection is called which will set m_data to zero
         if (gdk_selection_owner_get( g_clipboardAtom ) == m_clipboardWidget->window)
         {
             m_waiting = TRUE;
-           
-            gtk_selection_owner_set( (GtkWidget*) NULL, g_clipboardAtom, GDK_CURRENT_TIME );
-           
+
+            gtk_selection_owner_set( (GtkWidget*) NULL, g_clipboardAtom,
+                                     (guint32) GDK_CURRENT_TIME );
+
             while (m_waiting) gtk_main_iteration();
         }
-    
+
         if (gdk_selection_owner_get( GDK_SELECTION_PRIMARY ) == m_clipboardWidget->window)
         {
             m_waiting = TRUE;
-           
-            gtk_selection_owner_set( (GtkWidget*) NULL, GDK_SELECTION_PRIMARY, GDK_CURRENT_TIME );
-           
+
+            gtk_selection_owner_set( (GtkWidget*) NULL, GDK_SELECTION_PRIMARY,
+                                     (guint32) GDK_CURRENT_TIME );
+
             while (m_waiting) gtk_main_iteration();
         }
-    
+
         if (m_data)
-        { 
-           delete m_data;
-           m_data = (wxDataObject*) NULL;
-       }
-       
+        {
+            delete m_data;
+            m_data = (wxDataObject*) NULL;
+        }
+
 #if wxUSE_THREADS
         /* re-enable GUI threads */
-        wxapp_install_thread_wakeup();
 #endif
     }
-  
+
     m_targetRequested = 0;
     m_formatSupported = FALSE;
 }
@@ -436,18 +367,18 @@ void wxClipboard::Clear()
 bool wxClipboard::Open()
 {
     wxCHECK_MSG( !m_open, FALSE, wxT("clipboard already open") );
-  
+
     m_open = TRUE;
-    
+
     return TRUE;
 }
 
 bool wxClipboard::SetData( wxDataObject *data )
 {
     wxCHECK_MSG( m_open, FALSE, wxT("clipboard not open") );
-  
+
     wxCHECK_MSG( data, FALSE, wxT("data is invalid") );
-  
+
     Clear();
 
     return AddData( data );
@@ -456,177 +387,208 @@ bool wxClipboard::SetData( wxDataObject *data )
 bool wxClipboard::AddData( wxDataObject *data )
 {
     wxCHECK_MSG( m_open, FALSE, wxT("clipboard not open") );
-  
+
     wxCHECK_MSG( data, FALSE, wxT("data is invalid") );
-    
-    /* we can only store one wxDataObject */
+
+    // we can only store one wxDataObject
     Clear();
-  
+
     m_data = data;
 
-    /* This should happen automatically, but to be on the safe side */
-    m_ownsClipboard = FALSE;
-    m_ownsPrimarySelection = FALSE;
-    
-    /* get formats from wxDataObjects */
+    // get formats from wxDataObjects
     wxDataFormat *array = new wxDataFormat[ m_data->GetFormatCount() ];
     m_data->GetAllFormats( array );
-    
+
+    // primary selection or clipboard
+    GdkAtom clipboard = m_usePrimary ? (GdkAtom)GDK_SELECTION_PRIMARY
+                                     : g_clipboardAtom;
+
+
     for (size_t i = 0; i < m_data->GetFormatCount(); i++)
     {
-        GdkAtom atom = array[i];
-       wxLogDebug( wxT("Clipboard Supported atom %s"), gdk_atom_name( atom ) );
-
-        /* Add handlers if someone requests data. We currently always
-          offer data to the clipboard and the primary selection. Maybe
-          we should make that depend on the usePrimary flag */
-          
-        gtk_selection_add_target( GTK_WIDGET(m_clipboardWidget), 
-                              GDK_SELECTION_PRIMARY,
-                             atom, 
-                             0 );  /* what is info ? */
-                            
-        gtk_selection_add_target( GTK_WIDGET(m_clipboardWidget), 
-                              g_clipboardAtom,
-                             atom, 
-                             0 );  /* what is info ? */
+        wxLogTrace( TRACE_CLIPBOARD,
+                    wxT("wxClipboard now supports atom %s"),
+                    array[i].GetId().c_str() );
+
+//        printf( "added %s\n", 
+//                    gdk_atom_name( array[i].GetFormatId() ) );
+                    
+        gtk_selection_add_target( GTK_WIDGET(m_clipboardWidget),
+                                  clipboard,
+                                  array[i],
+                                  0 );  /* what is info ? */
     }
 
     delete[] array;
-                            
-    gtk_signal_connect( GTK_OBJECT(m_clipboardWidget), 
+
+    gtk_signal_connect( GTK_OBJECT(m_clipboardWidget),
                         "selection_get",
-                       GTK_SIGNAL_FUNC(selection_handler), 
-                       (gpointer) NULL );
+                        GTK_SIGNAL_FUNC(selection_handler),
+                        (gpointer) NULL );
 
 #if wxUSE_THREADS
-        /* disable GUI threads */
-        wxapp_uninstall_thread_wakeup();
+    /* disable GUI threads */
 #endif
-    
+
     /* Tell the world we offer clipboard data */
-    if (!gtk_selection_owner_set( m_clipboardWidget, 
-                                  g_clipboardAtom,
-                                 GDK_CURRENT_TIME ))
-    {
-#if wxUSE_THREADS
-        /* re-enable GUI threads */
-        wxapp_install_thread_wakeup();
-#endif
-        return FALSE;
-    }
-    m_ownsClipboard = TRUE;
-    
-    if (!gtk_selection_owner_set( m_clipboardWidget, 
-                                  GDK_SELECTION_PRIMARY,
-                                 GDK_CURRENT_TIME ))
-    {  
-#if wxUSE_THREADS
-        /* re-enable GUI threads */
-        wxapp_install_thread_wakeup();
-#endif
-        return FALSE;
-    }
-    m_ownsPrimarySelection = TRUE;
-    
+    bool res = (gtk_selection_owner_set( m_clipboardWidget,
+                                         clipboard,
+                                         (guint32) GDK_CURRENT_TIME ));
+
+    if (m_usePrimary)
+        m_ownsPrimarySelection = res;
+    else
+        m_ownsClipboard = res;
+
 #if wxUSE_THREADS
     /* re-enable GUI threads */
-    wxapp_install_thread_wakeup();
 #endif
-       
-    return TRUE;
+
+    return res;
 }
 
 void wxClipboard::Close()
 {
     wxCHECK_RET( m_open, wxT("clipboard not open") );
-    
+
     m_open = FALSE;
 }
 
+bool wxClipboard::IsOpened() const
+{
+    return m_open;
+}
+
 bool wxClipboard::IsSupported( const wxDataFormat& format )
 {
+    /* reentrance problems */
+    if (m_waiting) return FALSE;
+
     /* store requested format to be asked for by callbacks */
-    
     m_targetRequested = format;
-  
+
+#if 0
+    wxLogTrace( TRACE_CLIPBOARD,
+                wxT("wxClipboard:IsSupported: requested format: %s"),
+                format.GetId().c_str() );
+#endif
+
     wxCHECK_MSG( m_targetRequested, FALSE, wxT("invalid clipboard format") );
-    
+
     m_formatSupported = FALSE;
-  
-    /* perform query. this will set m_formatSupported to 
+
+    /* perform query. this will set m_formatSupported to
        TRUE if m_targetRequested is supported.
-       alsom we have to wait for the "answer" from the 
+       also, we have to wait for the "answer" from the
        clipboard owner which is an asynchronous process.
        therefore we set m_waiting = TRUE here and wait
-       until the callback "targets_selection_received" 
+       until the callback "targets_selection_received"
        sets it to FALSE */
 
     m_waiting = TRUE;
 
     gtk_selection_convert( m_targetsWidget,
-                          m_usePrimary ? GDK_SELECTION_PRIMARY : g_clipboardAtom, 
-                          g_targetsAtom,
-                          GDK_CURRENT_TIME );
+                           m_usePrimary ? (GdkAtom)GDK_SELECTION_PRIMARY
+                                        : g_clipboardAtom,
+                           g_targetsAtom,
+                           (guint32) GDK_CURRENT_TIME );
 
     while (m_waiting) gtk_main_iteration();
-    
+
     if (!m_formatSupported) return FALSE;
-    
+
     return TRUE;
-}    
-    
+}
+
 bool wxClipboard::GetData( wxDataObject& data )
 {
     wxCHECK_MSG( m_open, FALSE, wxT("clipboard not open") );
-    
+
     /* get formats from wxDataObjects */
     wxDataFormat *array = new wxDataFormat[ data.GetFormatCount() ];
     data.GetAllFormats( array );
-    
+
     for (size_t i = 0; i < data.GetFormatCount(); i++)
     {
+        wxDataFormat format( array[i] );
+
+        wxLogTrace( TRACE_CLIPBOARD,
+                    wxT("wxClipboard::GetData: requested format: %s"),
+                    format.GetId().c_str() );
+
         /* is data supported by clipboard ? */
-        if (!IsSupported( array[i] ))
-          continue;
-    
+
+        /* store requested format to be asked for by callbacks */
+        m_targetRequested = format;
+
+        wxCHECK_MSG( m_targetRequested, FALSE, wxT("invalid clipboard format") );
+
+        m_formatSupported = FALSE;
+
+       /* perform query. this will set m_formatSupported to
+          TRUE if m_targetRequested is supported.
+          also, we have to wait for the "answer" from the
+          clipboard owner which is an asynchronous process.
+          therefore we set m_waiting = TRUE here and wait
+          until the callback "targets_selection_received"
+          sets it to FALSE */
+
+        m_waiting = TRUE;
+
+        gtk_selection_convert( m_targetsWidget,
+                           m_usePrimary ? (GdkAtom)GDK_SELECTION_PRIMARY
+                                        : g_clipboardAtom,
+                           g_targetsAtom,
+                           (guint32) GDK_CURRENT_TIME );
+
+        while (m_waiting) gtk_main_iteration();
+
+        if (!m_formatSupported) continue;
+
         /* store pointer to data object to be filled up by callbacks */
         m_receivedData = &data;
-    
+
         /* store requested format to be asked for by callbacks */
-        m_targetRequested = array[i];
-  
+        m_targetRequested = format;
+
         wxCHECK_MSG( m_targetRequested, FALSE, wxT("invalid clipboard format") );
-    
+
         /* start query */
         m_formatSupported = FALSE;
-  
-        /* ask for clipboard contents.  this will set 
-           m_formatSupported to TRUE if m_targetRequested 
+
+        /* ask for clipboard contents.  this will set
+           m_formatSupported to TRUE if m_targetRequested
            is supported.
-           also, we have to wait for the "answer" from the 
+           also, we have to wait for the "answer" from the
            clipboard owner which is an asynchronous process.
            therefore we set m_waiting = TRUE here and wait
-           until the callback "targets_selection_received" 
+           until the callback "targets_selection_received"
            sets it to FALSE */
 
         m_waiting = TRUE;
 
+        wxLogTrace( TRACE_CLIPBOARD,
+                    wxT("wxClipboard::GetData: format found, start convert") );
+
         gtk_selection_convert( m_clipboardWidget,
-                          m_usePrimary ? GDK_SELECTION_PRIMARY : g_clipboardAtom, 
-                          m_targetRequested,
-                          GDK_CURRENT_TIME );
-  
+                               m_usePrimary ? (GdkAtom)GDK_SELECTION_PRIMARY
+                                            : g_clipboardAtom,
+                               m_targetRequested,
+                               (guint32) GDK_CURRENT_TIME );
+
         while (m_waiting) gtk_main_iteration();
 
         /* this is a true error as we checked for the presence of such data before */
         wxCHECK_MSG( m_formatSupported, FALSE, wxT("error retrieving data from clipboard") );
-       
-       /* return success */
+
+        /* return success */
         delete[] array;
         return TRUE;
     }
-  
+
+    wxLogTrace( TRACE_CLIPBOARD,
+                wxT("wxClipboard::GetData: format not found") );
+
     /* return failure */
     delete[] array;
     return FALSE;