there is memory leak problem with your mymarqueetest code will u plz tell me how to remove that memory leak plz conact me or reply on pankaj.chikh...@gmail.com its urgent plz reply me as soon as possible
Micah Carrick wrote: > > In the book "Foundations of GTK+ Development", there is a chapter on > creating custom widgets in which a marquee widget is created (which > scrolls text across the widget). > > You could take a look at the source code from the book available at > www.gtkbook.com > > - Micah Carrick > > Developer - http://www.micahcarrick.com > GTK+ Forums - http://www.gtkforums.com > > > > Tuvok wrote: >> Hi, >> >> What I need to do, is to make a bar with scrolling text inside it (like >> the bars with stock prices on tv). >> >> I've tried two methods, both of which are very slow. I've done it with >> Canvas and with Cairo. Below follows code. >> >> Did I do something wrong? Is there a way to make this code run faster? >> Should I use some different libraries for it? >> >> >> Rendering 4 such windows (1680x50) takes up 40-50% on both cores (AMD >> X2, 2.4GHz). >> >> >> >> Method I: Canvas >> >> The rendering part of code: >> >> GtkWidget *canvasWdg; >> GnomeCanvasItem *text; >> GnomeCanvasGroup *rootGroup; >> >> ifstream in(filename); >> string textLine; >> getline(in, textLine); >> >> canvasWdg = gnome_canvas_new(); >> >> gtk_container_add(GTK_CONTAINER(window), canvasWdg); >> >> gnome_canvas_set_scroll_region(GNOME_CANVAS(canvasWdg), 0.0, 0.0, >> width*1.0, >> height*1.0); >> rootGroup = gnome_canvas_root(GNOME_CANVAS(canvasWdg)); >> >> text = gnome_canvas_item_new(rootGroup, GNOME_TYPE_CANVAS_TEXT, "x", >> 0.0, "y", 0.0, "text", textLine.c_str(), >> "anchor", GTK_ANCHOR_NW, >> "fill_color", "white", "size", >> (int)((height*0.7)*1000), >> "size-set", TRUE, NULL); >> >> double x1, x2, y1, y2; >> gnome_canvas_item_get_bounds(GNOME_CANVAS_ITEM(text), &x1, &y1, &x2, >> &y2); >> // align the text in window: >> gnome_canvas_item_move(GNOME_CANVAS_ITEM(text), 1.0*width, >> ((height*1.0)/2-(y2-y1)/2)); >> >> g_timeout_add(40, moveText, text); >> >> gtk_widget_show_all(window); >> >> and the timeout function: >> >> gboolean moveText(void *text) >> { >> >> gnome_canvas_item_move(GNOME_CANVAS_ITEM((GnomeCanvasItem*)text), >> -2.0, 0.0); >> >> return TRUE; >> } >> >> >> >> Method II: Cairo >> >> I've made a Gtk widget, which draws with cairo on expose event; I'll put >> here only the expose function: >> >> static gboolean mdk_text_scroller_expose(GtkWidget *textScroller, >> GdkEventExpose *event) >> { >> >> MdkTextScroller *ts = MDK_TEXT_SCROLLER(textScroller); >> >> >> cairo_t *cr; >> >> cr = gdk_cairo_create(textScroller->window); >> >> >> >> gdk_cairo_region(cr, >> event->region); >> >> >> cairo_clip(cr); >> >> >> >> >> cairo_select_font_face(cr, "Sans", CAIRO_FONT_SLANT_NORMAL, >> CAIRO_FONT_WEIGHT_NORMAL); >> >> cairo_set_font_size(cr, ts->size); >> cairo_move_to(cr, ts->x+ts->xOffset, ts->y+ts->yOffset); >> cairo_set_source_rgb(cr, 1.0, 1.0, 1.0); >> cairo_show_text(cr, ts->text); >> >> if (ts->width == 0 || ts->height == 0) >> { >> cairo_text_extents_t ext; >> cairo_text_extents(cr, ts->text, &ext); >> ts->width = ext.width; >> ts->height = ext.height; >> } >> >> if (ts->width+ts->xOffset+100 < 0) >> { >> cairo_move_to(cr, ts->x+ts->xOffset+ts->width+100, ts->y >> +ts->yOffset); >> cairo_show_text(cr, ts->text); >> } >> >> if (ts->x+ts->xOffset+ts->width < 0) >> { >> ts->xOffset=ts->xOffset+ts->width+100; >> } >> >> >> cairo_stroke(cr); >> >> cairo_destroy(cr); >> } >> >> it's then redrawn with the same timeout call: >> >> gboolean moveText(void *text) >> { >> mdk_change_text_position((GtkWidget*)text, -1, 0); >> gtk_widget_queue_draw((GtkWidget*)text); >> >> return TRUE; >> } >> >> >> > _______________________________________________ > gtk-app-devel-list mailing list > gtk-app-devel-list@gnome.org > http://mail.gnome.org/mailman/listinfo/gtk-app-devel-list > > -- View this message in context: http://www.nabble.com/Scrolling-text-in-Gtk-tp17471895p25477546.html Sent from the Gtk+ - Apps Dev mailing list archive at Nabble.com. _______________________________________________ gtk-app-devel-list mailing list gtk-app-devel-list@gnome.org http://mail.gnome.org/mailman/listinfo/gtk-app-devel-list
