How to change GTK+3 label color dynamically

[Rúben Rodrigues]

Hi,

Now i need to change GtkLabel color dinamically, so i thing that i can't 
use Css to do this.. I do this in Gtk2:

gtk_widget_modify_fg(GTK_WIDGET(gtk_builder_get_object(builder,"label")),GTK_STATE_NORMAL,
 
);

How can i change the color in Gtk3?

Thanks

___
gtk-app-devel-list mailing list
gtk-app-devel-list@gnome.org
https://mail.gnome.org/mailman/listinfo/gtk-app-devel-list

Re: gtk3 layout background image

[Rúben Rodrigues]

Hi again,

I tested with GtkBox and don't works.. My code is correct?

GFile *file= g_file_new_for_path("custom.css");
 GtkStyleProvider *css_provider = 
GTK_STYLE_PROVIDER(gtk_css_provider_new());
gtk_css_provider_load_from_file(GTK_CSS_PROVIDER(css_provider), file, 
);
 gtk_style_context_reset_widgets(gdk_screen_get_default());

custom.css:

GtkBox#Home_PrincipalScreen_table.background{
 background-image: url('background.png');
}

GtkLabel#Home_Cooling_Tunnel1_Cooler_label1{
 color: white;
}

GtkLabel#Home_Sensors_MoistAvg_value{
 font-family: Segoe UI;
 font-weight: lighter;
 font-size: 25px;
}


Thanks


On 14-03-2017 14:46, Emmanuele Bassi wrote:
> On 14 March 2017 at 14:31, Rúben Rodrigues  wrote:
>> Just window can have background?
> I was referring to GdkWindow, not GtkWindow.
>
> GtkBox draws background, for instance; GtkGrid does as well.
>
>> I don't know why is a violation, because in my case my
>> applicationdoesn't make sense without background image..
> I think the issue, here, is that you're not aware that 15 years passed
> in the internals of GTK+.
>
> Changing the background pixmap of a GdkWindow is a layering violation
> because it assumes that you're essentially working on X11 and you
> control the X server as well; on X11, you're telling the X server to
> clear the contents of the native window used by GtkLayout using the
> bytes you're passing. This worked in 1997, but it's not how modern
> toolkits work — and it's not even how different windowing systems
> work. Widgets do not have their own native window for rendering any
> more, for instance.
>
> If your application window has a background image then use the
> background-image CSS property on your GtkWindow widget.
>
> Ciao,
>   Emmanuele.
>
>> On 14-03-2017 14:01, Emmanuele Bassi wrote:
>>> You were not changing the background with your theme: you were
>>> programmatically replacing the base pixmap of the GdkWindow used by
>>> GtkLayout. It was essentially a layering violation, and would actually
>>> break your theme.
>>>
>>> The API reference for each GTK widget should tell you the CSS styling
>>> available; see the "CSS nodes" section, for instance, of GtkBox:
>>> https://developer.gnome.org/gtk3/stable/GtkBox.html
>>>
>>> Ciao,
>>>Emmanuele.
>>>
>>>
>>> On 14 March 2017 at 13:55, Rúben Rodrigues  wrote:
 Thanks!

 But in GTK+2 we could change background in layout with this:

 // Set picture as background.
 //gdk_pixbuf_render_pixmap_and_mask (pixbuf, , NULL, 0);
 //style = gtk_style_new ();
 //style->bg_pixmap[0] = background;
 //homeWindow = GTK_WIDGET(gtk_builder_get_object(builder,
 "layout_Home"));
 //gtk_widget_set_style (GTK_WIDGET(homeWindow), GTK_STYLE(style));

 How i know witch containers draw background?

 THanks


 On 14-03-2017 12:55, Emmanuele Bassi wrote:
> Not all GTK containers draw a background, mostly for historical
> reasons. This has been true for GTK 1.x, 2.x, and 3.x.
>
> In particular, GtkLayout does not draw any background with CSS, so you
> will need to either subclass GtkLayout, override the GtkWidget::draw
> virtual function, and call gtk_render_* functions yourself; or you
> will need to put a GtkLayout into a parent container that does draw a
> background. You will, of course, need to style the parent container's
> background, not the GtkLayout itself.
>
> Ciao,
> Emmanuele.
>
>
> On 14 March 2017 at 12:43, Rúben Rodrigues  wrote:
>> I verify that i can't use css provider, don't works.
>>
>> My css file is :
>>
>> GtkLayout#layout_Home.background{
>> background-image: url('background.png');
>> }
>>
>> GtkLabel#Home_Cooling_Tunnel1_Cooler_label1{
>> color: white;
>> }
>>
>> GtkLabel#Home_Sensors_MoistAvg_value{
>> font-family: Segoe UI;
>> font-weight: lighter;
>> font-size: 25px;
>> }
>>
>> And this code:
>>
>> static void apply_css(GtkWidget *widget, GtkStyleProvider *provider)
>> {
>> gtk_style_context_add_provider(gtk_widget_get_style_context(widget),
>> GTK_STYLE_PROVIDER(provider),G_MAXUINT);
>> if(GTK_IS_CONTAINER(widget))
>> gtk_container_forall(GTK_CONTAINER(widget),(GtkCallback)
>> apply_css,provider);
>>
>> }
>>
>> GFile *file= g_file_new_for_path("custom.css");
>> GtkStyleProvider *css_provider =
>> GTK_STYLE_PROVIDER(gtk_css_provider_new());
>> gtk_css_provider_load_from_file(GTK_CSS_PROVIDER(css_provider), file,
>> );
>> apply_css(gtk_builder_get_object(builder,"window_Main"),css_provider);
>>
>> This is the code used in gtk3-demo and don't works for me.. Why
>>
>> THanks

Re: gtk3 layout background image

[Rúben Rodrigues]

Thanks, it works!


On 15-03-2017 12:49, mhora...@gmail.com wrote:
> You need to give the widget a "name" property - than you can select it
> in CSS!
>
> Best,
> Martin
>
> On Wed, 2017-03-15 at 10:28 +, Rúben Rodrigues wrote:
>> Hi,
>>
>> I see now, that the problem i'm not do in correct mode. I do this:
>>
>> GtkButton{
>>
>>   color: blue;
>> }
>>
>> and works. All buttons change to blue color. But when i'm changing a
>> specific label or GtkBox to put background i do this:
>>
>> GtkLabel#label_Avg_Temp_value{
>>   color: red;
>>   font-family: Segoe UI;
>>   font-size: 25px;
>> }
>>
>> And don't change label_Avg_Temp_value . What is the correct way to
>> change a specific widget?
>>
>> Thanks
>>
>>
>> Às 14:46 de 14/03/2017, Emmanuele Bassi escreveu:
>>> On 14 March 2017 at 14:31, Rúben Rodrigues 
>>> wrote:
 Just window can have background?
>>> I was referring to GdkWindow, not GtkWindow.
>>>
>>> GtkBox draws background, for instance; GtkGrid does as well.
>>>
 I don't know why is a violation, because in my case my
 applicationdoesn't make sense without background image..
>>> I think the issue, here, is that you're not aware that 15 years
>>> passed
>>> in the internals of GTK+.
>>>
>>> Changing the background pixmap of a GdkWindow is a layering
>>> violation
>>> because it assumes that you're essentially working on X11 and you
>>> control the X server as well; on X11, you're telling the X server
>>> to
>>> clear the contents of the native window used by GtkLayout using the
>>> bytes you're passing. This worked in 1997, but it's not how modern
>>> toolkits work — and it's not even how different windowing systems
>>> work. Widgets do not have their own native window for rendering any
>>> more, for instance.
>>>
>>> If your application window has a background image then use the
>>> background-image CSS property on your GtkWindow widget.
>>>
>>> Ciao,
>>>Emmanuele.
>>>
 On 14-03-2017 14:01, Emmanuele Bassi wrote:
> You were not changing the background with your theme: you were
> programmatically replacing the base pixmap of the GdkWindow
> used by
> GtkLayout. It was essentially a layering violation, and would
> actually
> break your theme.
>
> The API reference for each GTK widget should tell you the CSS
> styling
> available; see the "CSS nodes" section, for instance, of
> GtkBox:
> https://developer.gnome.org/gtk3/stable/GtkBox.html
>
> Ciao,
> Emmanuele.
>
>
> On 14 March 2017 at 13:55, Rúben Rodrigues  t> wrote:
>> Thanks!
>>
>> But in GTK+2 we could change background in layout with this:
>>
>> // Set picture as background.
>> //gdk_pixbuf_render_pixmap_and_mask (pixbuf,
>> , NULL, 0);
>> //style = gtk_style_new ();
>> //style->bg_pixmap[0] = background;
>> //homeWindow =
>> GTK_WIDGET(gtk_builder_get_object(builder,
>> "layout_Home"));
>> //gtk_widget_set_style (GTK_WIDGET(homeWindow),
>> GTK_STYLE(style));
>>
>> How i know witch containers draw background?
>>
>> THanks
>>
>>
>> On 14-03-2017 12:55, Emmanuele Bassi wrote:
>>> Not all GTK containers draw a background, mostly for
>>> historical
>>> reasons. This has been true for GTK 1.x, 2.x, and 3.x.
>>>
>>> In particular, GtkLayout does not draw any background with
>>> CSS, so you
>>> will need to either subclass GtkLayout, override the
>>> GtkWidget::draw
>>> virtual function, and call gtk_render_* functions yourself;
>>> or you
>>> will need to put a GtkLayout into a parent container that
>>> does draw a
>>> background. You will, of course, need to style the parent
>>> container's
>>> background, not the GtkLayout itself.
>>>
>>> Ciao,
>>>  Emmanuele.
>>>
>>>
>>> On 14 March 2017 at 12:43, Rúben Rodrigues >> om.pt> wrote:
 I verify that i can't use css provider, don't works.

 My css file is :

 GtkLayout#layout_Home.background{
  background-image: url('background.png');
 }

 GtkLabel#Home_Cooling_Tunnel1_Cooler_label1{
  color: white;
 }

 GtkLabel#Home_Sensors_MoistAvg_value{
  font-family: Segoe UI;
  font-weight: lighter;
  font-size: 25px;
 }

 And this code:

 static void apply_css(GtkWidget *widget, GtkStyleProvider
 *provider)
 {
 gtk_style_context_add_provider(gtk_widget_get_style_conte
 xt(widget),
 GTK_STYLE_PROVIDER(provider),G_MAXUINT);
  if(GTK_IS_CONTAINER(widget))
  gtk_container_forall(GTK_CONTAINER(widget),(G
 tkCallback)
 

Re: gtk3 layout background image

[Rúben Rodrigues]

Hi,

I see now, that the problem i'm not do in correct mode. I do this:

GtkButton{

 color: blue;
}

and works. All buttons change to blue color. But when i'm changing a 
specific label or GtkBox to put background i do this:

GtkLabel#label_Avg_Temp_value{
 color: red;
 font-family: Segoe UI;
 font-size: 25px;
}

And don't change label_Avg_Temp_value . What is the correct way to 
change a specific widget?

Thanks


Às 14:46 de 14/03/2017, Emmanuele Bassi escreveu:
> On 14 March 2017 at 14:31, Rúben Rodrigues  wrote:
>> Just window can have background?
> I was referring to GdkWindow, not GtkWindow.
>
> GtkBox draws background, for instance; GtkGrid does as well.
>
>> I don't know why is a violation, because in my case my
>> applicationdoesn't make sense without background image..
> I think the issue, here, is that you're not aware that 15 years passed
> in the internals of GTK+.
>
> Changing the background pixmap of a GdkWindow is a layering violation
> because it assumes that you're essentially working on X11 and you
> control the X server as well; on X11, you're telling the X server to
> clear the contents of the native window used by GtkLayout using the
> bytes you're passing. This worked in 1997, but it's not how modern
> toolkits work — and it's not even how different windowing systems
> work. Widgets do not have their own native window for rendering any
> more, for instance.
>
> If your application window has a background image then use the
> background-image CSS property on your GtkWindow widget.
>
> Ciao,
>   Emmanuele.
>
>> On 14-03-2017 14:01, Emmanuele Bassi wrote:
>>> You were not changing the background with your theme: you were
>>> programmatically replacing the base pixmap of the GdkWindow used by
>>> GtkLayout. It was essentially a layering violation, and would actually
>>> break your theme.
>>>
>>> The API reference for each GTK widget should tell you the CSS styling
>>> available; see the "CSS nodes" section, for instance, of GtkBox:
>>> https://developer.gnome.org/gtk3/stable/GtkBox.html
>>>
>>> Ciao,
>>>Emmanuele.
>>>
>>>
>>> On 14 March 2017 at 13:55, Rúben Rodrigues  wrote:
 Thanks!

 But in GTK+2 we could change background in layout with this:

 // Set picture as background.
 //gdk_pixbuf_render_pixmap_and_mask (pixbuf, , NULL, 0);
 //style = gtk_style_new ();
 //style->bg_pixmap[0] = background;
 //homeWindow = GTK_WIDGET(gtk_builder_get_object(builder,
 "layout_Home"));
 //gtk_widget_set_style (GTK_WIDGET(homeWindow), GTK_STYLE(style));

 How i know witch containers draw background?

 THanks


 On 14-03-2017 12:55, Emmanuele Bassi wrote:
> Not all GTK containers draw a background, mostly for historical
> reasons. This has been true for GTK 1.x, 2.x, and 3.x.
>
> In particular, GtkLayout does not draw any background with CSS, so you
> will need to either subclass GtkLayout, override the GtkWidget::draw
> virtual function, and call gtk_render_* functions yourself; or you
> will need to put a GtkLayout into a parent container that does draw a
> background. You will, of course, need to style the parent container's
> background, not the GtkLayout itself.
>
> Ciao,
> Emmanuele.
>
>
> On 14 March 2017 at 12:43, Rúben Rodrigues  wrote:
>> I verify that i can't use css provider, don't works.
>>
>> My css file is :
>>
>> GtkLayout#layout_Home.background{
>> background-image: url('background.png');
>> }
>>
>> GtkLabel#Home_Cooling_Tunnel1_Cooler_label1{
>> color: white;
>> }
>>
>> GtkLabel#Home_Sensors_MoistAvg_value{
>> font-family: Segoe UI;
>> font-weight: lighter;
>> font-size: 25px;
>> }
>>
>> And this code:
>>
>> static void apply_css(GtkWidget *widget, GtkStyleProvider *provider)
>> {
>> gtk_style_context_add_provider(gtk_widget_get_style_context(widget),
>> GTK_STYLE_PROVIDER(provider),G_MAXUINT);
>> if(GTK_IS_CONTAINER(widget))
>> gtk_container_forall(GTK_CONTAINER(widget),(GtkCallback)
>> apply_css,provider);
>>
>> }
>>
>> GFile *file= g_file_new_for_path("custom.css");
>> GtkStyleProvider *css_provider =
>> GTK_STYLE_PROVIDER(gtk_css_provider_new());
>> gtk_css_provider_load_from_file(GTK_CSS_PROVIDER(css_provider), file,
>> );
>> apply_css(gtk_builder_get_object(builder,"window_Main"),css_provider);
>>
>> This is the code used in gtk3-demo and don't works for me.. Why
>>
>> THanks
>>
>> On 14-03-2017 10:00, Rúben Rodrigues wrote:
>>> Hi guys,
>>>
>>> Finnaly i migrate my application to gtk+3. So, now i neet to change some
>>> things like image background. I used 

Re: How to set initial size of TextView?

[Chris Green]

Eric Cashon via gtk-app-devel-list  wrote:
> 
>  
> Hi Chris,
> 
> Try getting the font height and base the textview height on that. If you 
> use the font ascent you might have to pad it a little but it should give 
> you a consistent value to size your textviews with based on font size. 
> 
> 
OK, thanks (and thanks for the sample code too).

I'm surprised that there's no easier way of doing it but if there
isn't then that's just the way it is I suppose.

-- 
Chris Green
·

___
gtk-app-devel-list mailing list
gtk-app-devel-list@gnome.org
https://mail.gnome.org/mailman/listinfo/gtk-app-devel-list