I'm trying to create a transparent, non-decorated popup GtkWindow on top af my app HildonWindow and draw something on its underlying GdkWindow object using cairo.<br>All I was able to obtain so far is a black (or whatever is the background colour of the selected theme) rectangle -ie it's not transparent and everything I paint in its GdkWindow with Cairo is not showed at all.<br>
Here is the code I'm using:<br><br>void create_image_details(GtkWidget *callerobj,app_data_t *myapp) {<br> PangoLayout *textbuff;<br> cairo_t *cr;<br> gint x0, y0, r, txtwidth, txtheight;<br><br> /* For the widget itself let's use a GtkWindow */<br>
if ((myapp->imgparamwin != NULL) & GTK_IS_WINDOW(myapp->imgparamwin)) gtk_widget_destroy(myapp->imgparamwin);<br> myapp->imgparamwin = gtk_window_new(GTK_WINDOW_POPUP);<br> gtk_window_set_decorated(GTK_WINDOW (myapp->imgparamwin),FALSE);<br>
gtk_window_set_opacity(GTK_WINDOW (myapp->imgparamwin),0);<br> gtk_widget_set_app_paintable(myapp->imgparamwin,TRUE);<br> gtk_widget_realize(myapp->imgparamwin);<br> /* gdk_window_set_back_pixmap(myapp->imgparamwin->window,NULL,FALSE); */<br>
/* Get the Cairo context */<br> cr = gdk_cairo_create(GDK_DRAWABLE (myapp->imgparamwin->window));<br> textbuff = pango_cairo_create_layout(cr);<br> pango_layout_set_markup(textbuff,myapp->imgparam,-1);<br>
pango_layout_get_pixel_size(textbuff,&txtwidth,&txtheight);<br> /* Draw a rounded rectangle */<br> <br>[cairo stuff is here]<br><br> cairo_destroy(cr);<br> g_object_unref(textbuff);<br> /* Show the widget */<br>
gtk_window_resize(GTK_WINDOW (myapp->imgparamwin),txtwidth + (r * 2),txtheight + (r * 2));<br> gtk_window_move(GTK_WINDOW (myapp->imgparamwin),30,30);<br> gdk_window_reparent(myapp->imgparamwin->window,myapp->image->window,30,30);<br>
gtk_widget_show_all(myapp->imgparamwin);<br>}<br><br>The window dimension after the gtk_window_resize() are correct -ie the dimension of the PangoLayout containing the text to be rendered, so something is definitely going on under the hood... but nothing is displayed!<br>
If I add some widget to the popoup window (for example a GtkLabel with some text in it), it's rendered correctly, but, of course it's not transparent!<br><br>Any help, as always, is much appreciated!<br><br>Luca Donaggio<br>