Re: is there a signal for typing at bottom of window?

[Doug McCasland <dougm bravoecho net>]

Thanks Joël,

I don't see how your code reacts to scrolling ? But I used your idea to
check the buffer length.  That helped filter out a lot of the signals.  But
other non-keyboard actions can change the buffer length, of course, so it's
not dependable.  :-/


On Tue, Sep 25, 2018 at 10:17 PM Joël Krähemann <jkraehemann gmail com>
wrote:

> Hi again,
>
> For sure you should probably use:
>
> g_signal_connect_after(your_text_buffer, "changed",
>   G_CALLBACK(your_text_buffer_changed_callback), your_data);
>
> and YOUR_DATA(your_data) just casts to your pointer to a struct or
> object containing some information:
>
> struct _YourData{
>   gint last_newline_position;
> };
>
> Well this is it.
>
> Bests,
> Joël
>
>
>
> On Wed, Sep 26, 2018 at 7:12 AM Joël Krähemann <jkraehemann gmail com>
> wrote:
> > Hi,
> >
> > g_object_get(your_text_view,
> >   "buffer", &your_text_buffer,
> >   NULL);
> > g_signal_connect(your_text_buffer, "changed",
> >   G_CALLBACK(your_text_buffer_changed_callback), your_data);
> >
> > void your_text_buffer_changed_callback(GtkTextBuffer
> > *your_text_buffer, gpointer your_data)
> > {
> >   gint line_count;
> >
> >   line_count = gtk_text_buffer_get_line_count(your_text_buffer);
> >
> >   if(line_count > YOUR_DATA(your_data)->line_count){
> >     gchar *your_text;
> >
> >     g_object_get(your_text_buffer,
> >       "text", &your_text,
> >       NULL);
> >
> >     if(your_text[strlen(your_text) - 1] == '\n' &&
> > YOUR_DATA(your_data)->last_newline_position <
> > &(your_text[strlen(your_text) - 1]) - your_text){
> >       //TODO:DMC: implement me
> >     }
> >   }
> > }
> >
> > by,
> > Joël
> >
> > On Wed, Sep 26, 2018 at 6:49 AM Doug McCasland <dougm bravoecho net>
> wrote:
> > > Eric, thanks for the ideas!
> > >
> > > I tried a bunch of things to distinguish the callbacks, but it got too
> > > complicated.  Checking for a different line number is a clever idea,
> but
> > > PgUp and PgDown also move the cursor which changes the line number.
> > >  Similar problems for tracking the char offset in the line (for simply
> > > typing at the end of the last visible line, not creating a new
> line/para).
> > > So, it would be nice if there was a simple signal for this case, where
> the
> > > window scrolls because of keyboard input in the last visible line.
> > >
> > > The reason I want this is, is so my app can scroll the window
> > > automatically, so that the cursor insert point becomes centered
> > > vertically.  In other words, when I'm typing a long paragraph, and
> it's the
> > > last visible line, I want it to scroll up, so I'm now typing in the
> middle
> > > of the window (vs. continuing to type on the last visible line).
> > >
> > > I suppose this is a bit esoteric.
> > >
> > > I did create a kbd shortcut to do that scroll manually:
> > >
> > > gtk_text_view_scroll_to_iter(..., 0.0, TRUE, 1.0, 0.5)
> > >
> > > so I have that to use.
> > >
> > >
> > > On Tue, Sep 25, 2018 at 2:34 PM <cecashon aol com> wrote:
> > >
> > > > Not sure how to go about this myself. I see the extra callbacks and
> it
> > > > would be a good thing to limit them. For filtering maybe check if the
> > > > cursor has changed lines along with the adjustment value change.
> Suspect
> > > > there is a better solution for this.
> > > >
> > > > static void value_changed(GtkAdjustment *v_adjust, gpointer textview)
> > > >   {
> > > >     static gint s_line=0;
> > > >     GtkTextIter iter;
> > > >     GtkTextBuffer
> > > > *buffer=gtk_text_view_get_buffer(GTK_TEXT_VIEW(textview));
> > > >     GtkTextMark *mark=gtk_text_buffer_get_mark(buffer, "insert");
> > > >     gtk_text_buffer_get_iter_at_mark(buffer, &iter, mark);
> > > >     gint line=gtk_text_iter_get_line(&iter);
> > > >     if(s_line!=line)
> > > >       {
> > > >         g_print("Scroll Line\n");
> > > >         s_line=line;
> > > >       }
> > > >   }
> > > >
> > > > Eric
> > > >
> > > >
> > > > -----Original Message-----
> > > > From: Doug McCasland <dougm bravoecho net>
> > > > To: cecashon <cecashon aol com>
> > > > Sent: Tue, Sep 25, 2018 2:10 pm
> > > > Subject: Re: is there a signal for typing at bottom of window?
> > > >
> > > > Actually I get 11 signals with a different setting of:
> > > > gtk_text_view_set_pixels_inside_wrap()
> > > >
> > > > So it's one signal per vertical pixel perhaps?   I can code for that.
> > > >
> > > > But I also I get those signals during any scrolling (scrollbar or
> > > > mousewheel).  How can I distinguish between automatic scrolling at
> bottom
> > > > and user-commanded scrolling?
> > > >
> > > > thanks
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > On Tue, Sep 25, 2018 at 1:47 PM Doug McCasland <dougm bravoecho net>
> > > > wrote:
> > > >
> > > > Woo-hoo, that works!
> > > >
> > > > BUT, I get 12 signals for each line that is auto-scrolled.  I can
> code for
> > > > this, but why 12?  Will it always be 12?
> > > >
> > > >
> > > > On Tue, Sep 25, 2018 at 11:46 AM <cecashon aol com> wrote:
> > > >
> > > >
> > > > Hi Doug,
> > > >
> > > > Try getting the vertical adjustment of the scrolled window and
> connect to
> > > > "value-changed". See if that will work. Something like
> > > >
> > > > ...
> > > > static void value_changed(GtkAdjustment *v_adjust, gpointer
> user_data)
> > > >   {
> > > >   }
> > > > ...
> > > > GtkWidget *scroll=gtk_scrolled_window_new(NULL, NULL);
> > > > GtkAdjustment
> *v_adjust=gtk_scrolled_window_get_vadjustment(GTK_SCROLLED_WINDOW(scroll));
> > > > g_signal_connect(v_adjust, "value-changed",
> G_CALLBACK(value_changed),
> > > > NULL);
> > > > ...
> > > >
> > > > Eric
> > > >
> > > >
> > > >
> > > >
> > > >
> > > > --
> > > > Doug McCasland   <dougm bravoecho net>
> > > >
> > > >
> > > >
> > > > --
> > > > Doug McCasland   <dougm bravoecho net>
> > >
> > >
> > > --
> > > Doug McCasland   <dougm bravoecho net>
> > > _______________________________________________
> > > gtk-app-devel-list mailing list
> > > gtk-app-devel-list gnome org
> > > https://mail.gnome.org/mailman/listinfo/gtk-app-devel-list


-- 
Doug McCasland   <dougm bravoecho net>