Re: [gtkmm] suffering from slow treeview

[gtkmm-list <gtkmm hakvoort be>]

Works great!
thanks for straightening things out.

Bart

On Thu, 2004-04-01 at 21:41, Matthew Walton wrote:
> gtkmm-list wrote:
> 
> > Thanks for the suggestion, it does speed thing up, but afais only when
> > you use a single color. I need alternating colors ( green,red,yellow) to
> > indicate the states of persons in list. And for that i need the line in 
> > Add() .
> > 
> > However, i found another solution for my problem today. i now use some
> > images from the Gtk::Stock collection icw render_icon() to indicate a
> > state. It's as clear as backgroundcolors and performance is MUCH better.
> > 
> > Still, i'm curious if there is a solution to this slow background
> > drawing. Any more ideas?
> 
> Yes. Try the attached variant. You'll notice it manages two colours 
> quite nicely, and I've not noticed any performance problems with it. The 
> background colour property is read from the color column in each row of 
> the TreeStore individually, just as the text property is, so you can 
> have as many colours as you like. If you don't understand why, I would 
> recommend reading the TreeView chapters of the gtkmm tutorial/book 
> available on http://www.gtkmm.org, and the various examples in the 
> distribution which use TreeViews (the stock browser, the TreeView demos 
> etc).
> 
> I may have changed a few std::strings to Glib::ustrings here and there, 
> but that's me being pedantic and shouldn't have any real effect on the 
> functioning of the program. Try it and see.
> 
> ______________________________________________________________________
> #include <gtkmm/treeview.h>
> #include <gtkmm/treestore.h>
> #include <gtkmm/window.h>
> #include <gtkmm/box.h>
> #include <gtkmm/button.h>
> #include <gtkmm/main.h>
> #include <gtkmm/scrolledwindow.h>
> 
> class DemoTree : public Gtk::TreeView
> {
>   private:
>     struct Columns : public Gtk::TreeModelColumnRecord             
>     {
>       Gtk::TreeModelColumn<Glib::ustring> column1;
>       Gtk::TreeModelColumn<Glib::ustring> color;
>       Columns() { add(column1);add(color); }
>     };
>     Columns columns;
> 
>     Gtk::CellRendererText* cell_renderer_text;
>     Gtk::TreeViewColumn* color_column;
>     Gtk::TreeRow row;
> 
> 
>   public:
>     Glib::RefPtr<Gtk::TreeStore> treestore;
> 
>     DemoTree()
>     {
>       treestore = Gtk::TreeStore::create( columns );
>       set_model( treestore );
> 
>       append_column("DemoColumn", columns.column1);
> 
>       color_column = get_column(0);
>       Gtk::CellRenderer* cell_renderer = color_column->get_first_cell_renderer();
>       cell_renderer_text = dynamic_cast<Gtk::CellRendererText*>(cell_renderer);
>       color_column->add_attribute(cell_renderer_text->property_background(), columns.color);
>     }
> 
>     void AddRow( const Glib::ustring &name, const Glib::ustring &colour )
>     {		
>       row = *(treestore->append());
>       row[columns.color] = colour;
> 
>       row[columns.column1] = name;
>     }
> 
> 
> };
> 
> class DemoWindow : public Gtk::Window
> {
>   DemoTree dt;
>   Gtk::ScrolledWindow scroll_window;
>   Gtk::VBox vbox_main;
>   Gtk::Button btn_Refresh;
> 
>   public:	
>   DemoWindow()
>   {
>     set_default_size( 400, 600 );
> 
>     scroll_window.add( dt );
>     scroll_window.set_policy(Gtk::POLICY_AUTOMATIC, Gtk::POLICY_AUTOMATIC);
>     vbox_main.pack_start( scroll_window );
> 
>     btn_Refresh.set_label("Refresh");
>     btn_Refresh.signal_clicked().connect( SigC::slot(*this, &DemoWindow::btn_refresh_click) );
>     vbox_main.pack_start( btn_Refresh, Gtk::PACK_SHRINK );
> 
> 
>     btn_refresh_click();//fill 'er up :P
> 
>     add(vbox_main);
>     show_all_children();
>   }
> 
>   void btn_refresh_click()
>   {
>     dt.treestore->clear();
>     for(int i = 0; i < 200; i++) dt.AddRow("TESTING", "blue");
>     for(int i = 0; i < 50; i++) dt.AddRow("TESTING", "red");
>   }
> };
> 
> 
> int main(int argc, char *argv[])
> {
>   Gtk::Main kit(argc, argv);
> 
>   DemoWindow dw;
>   Gtk::Main::run(dw);
> }