invoke row-activated with libgda-ui - c

Can someone provide a sample how to access to callbacks with Gnome-db libgda-ui, using this demo https://github.com/GNOME/libgda/blob/master/libgda-ui/demos/grid.c and I want to call a callback when I double click on a row like in gtktree with liststore

I think I've found a solution using the raw-grid
GtkWidget *grid;
GdauiRawGrid *raw_grid;
g_object_get (G_OBJECT (grid), "raw-grid", &raw_grid, NULL);
Then the raw_grid has the callback needed and it have methods like gtk treeview

Related

gtk_container_add function crashes

I have the following line in my GTK code:
gtk_container_add(GTK_CONTAINER(main_wind_ob->stack),
GTK_WIDGET(main_wind_ob->product_ob->swindow));
Where main_wind_on->stack is a GtkStack acquired this way
main_wind_ob->stack = GTK_STACK(
gtk_builder_get_object (
main_wind_ob->builder,
"stack"
)
);
Where main_wind_ob->builder is a GtkBuilder object associated with a .ui file where a GtkStack container is declared with the ID stack.
main_wind_ob->product_ob->swindow is a GtkScrolledWindow acquired like this:
main_wind_ob->product_ob->swindow =
gtk_scrolled_window_new(NULL, NULL);
I know neither main_wind_ob->product_ob->swindow or main_wind_ob->stack are not null as I've debugged and checked them.
What I wanted to do was make swindow be the child of the stack, but it just crashes when it reaches the gtk_container_add function call. I am not really sure why. Let me know if there is any extra details I can add to the post, thanks.

How do I replace lookup_widget in Glade3/GTK3 code?

I have recently resurrected a project from a decade ago (https://github.com/clancyj4/z80sim) and I'm running into problems that are related to the transition from glade 2 to 3.
One problem is that I use a function lookup_widget which is defined in support.c by glade 2, but is not defined in glade 3. And I don't know how to replace it.
An example of how I use it is:
void init_Code(GtkWidget *Main)
{
GtkWidget *widget;
PangoFontDescription *codefont;
codetext = lookup_widget(Main, "Code_Text");
code_textbuffer = gtk_text_view_get_buffer(GTK_TEXT_VIEW(codetext));
I have looked the problem up, of course, but I don't understand the answer which was:
The preferred solution is to pass a pointer to your ENTRY as the user data pointer when you connect the signal, or, if you're using gtk_builder_connect_signals(), store a pointer to ENTRY in your class and pass the class as the user data pointer.
which was referring to:
on_BT_OK_clicked(GtkButton *button, gpointer user_data)
{
//The line directly below is the one I get an error on
GtkWidget *entry = lookup_widget( GTK_WIDGET(button), "ENTRY" );
Any clarification would be most helpful.
EDIT:
I'm pretty sure that the signals are all connected because I use this:
builder = gtk_builder_new();
gtk_builder_add_from_file(builder, "z80em2.glade", NULL);
window = GTK_WIDGET(gtk_builder_get_object(builder, "Main"));
gtk_builder_connect_signals(builder, NULL);
As I understand it codetext = lookup_widget(Main, "Code_Text") returns a pointer to the GtkWidget referred to as Code_Text under the Main widget and I don't see how to do that in GTK3.
I haven't used Glade, but if you have "manual" code that connects the signal handler, you should pass a pointer to that other widget in that call. That will then be stored inside GTK+, and passed as the user_pointer argument to the event handler.
So it would become just:
on_BT_OK_clicked(GtkButton *button, gpointer user_data)
{
// This assumes the entry was passed to g_signal_connect() as 'data'
GtkWidget *entry = GTK_WIDGET(user_data);
See g_signal_connect().
If you are planning to rewrite this codebase heavily anyway, you may find it helpful to reorganize the widgets into composite widget templates, which Glade 3 supports, and use gtk_widget_class_bind_template_child() to make all the widgets that you would have otherwise looked up with lookup_widget() into members of your widget class. But it's not a good short-term fix, because it would involve a lot of refactoring.

How to pack widgets in a gtk_dialog window using gtk3

In gtk2 the following code snippet works to pack widgets into a gtk_dialog window, using the vbox and action_area of the GtkDialog structure:
window=gtk_dialog_new();
gtk_container_set_border_width((GtkContainer *)window, 0);
scrolled_window=gtk_scrolled_window_new(NULL,NULL);
gtk_container_set_border_width((GtkContainer *)scrolled_window, 10);
gtk_scrolled_window_set_shadow_type((GtkScrolledWindow *)scrolled_window, GTK_SHADOW_IN);
gtk_scrolled_window_set_policy((GtkScrolledWindow *)scrolled_window, GTK_POLICY_AUTOMATIC, GTK_POLICY_AUTOMATIC);
gtk_box_pack_start((GtkBox *) (GtkDialog *)window->vbox), scrolled_window, TRUE, TRUE, 0);
gtk_widget_show(scrolled_window);
label=gtk_label_new(text);
gtk_label_set_use_markup((GtkLabel *)label, TRUE);
gtk_label_set_selectable((GtkLabel *)label, TRUE);
gtk_label_set_line_wrap((GtkLabel *)label, FALSE);
gtk_scrolled_window_add_with_viewport((GtkScrolledWindow *)scrolled_window, label);
gtk_widget_show(label);
button=gtk_button_new_with_label("close");
g_signal_connect_swapped(button, "clicked", G_CALLBACK (gtk_widget_destroy), window);
gtk_widget_set_can_default(button, TRUE);
gtk_box_pack_start((GtkBox *) (GtkDialog *)window->action_area), button, TRUE, TRUE, 0);
gtk_widget_grab_default(button);
gtk_widget_show (button);
gtk_widget_show(window);
However in gtk3 this is not completely valid code any more. And it will not compile.
If I replace instances of:
(GtkBox *) (GtkDialog *)window->vbox
with:
(GtkBox *) (GtkDialog *)window
And do the same with instances of action_area the code will compile but the window will not show the extra packed widgets, just the ones the dialog comes with by default.
More information, which to me is a bit contradictory https://developer.gnome.org/gtk3/stable/GtkDialog.html#GtkDialog-struct
The GtkDialog contains only private fields and should not be directly
accessed.
But when I read this on the same page it seems to contradict the previous quote https://developer.gnome.org/gtk3/stable/GtkDialog.html#gtk-dialog-add-action-widget
If you want to add a non-activatable widget, simply pack it into the
action_area field of the GtkDialog struct.
Earlier in that document it states under GtkDialog as GtkBuildable
The GtkDialog implementation of the GtkBuildable interface exposes the
vbox and action_area as internal children with the names “vbox” and
“action_area”.
But I don't really know how to do that using the GtkBuildable interface neither do I want to. Or perhaps that is exactly what I did in gtk2 and it stopped working in gtk3...?
My question is how can I convert the gtk2 code to work with gtk3 with as few changes as possible. I have been searching for quite a while but found no answer yet. The existing gtk3 documentation leaves me going in circles. Maybe I just miss something totally obvious. Or perhaps you are not supposed to do this anymore and have to use a window instead of a dialog?
Thanks to the answer below I was able to change the code to this working one, it will also eliminate a deprecated warning about gtk_dialog_get_action_area() by using gtk_dialog_add_button()
window=gtk_dialog_new();
gtk_container_set_border_width((GtkContainer *)window, 0);
scrolled_window=gtk_scrolled_window_new(NULL,NULL);
gtk_container_set_border_width((GtkContainer *)scrolled_window, 10);
gtk_scrolled_window_set_shadow_type((GtkScrolledWindow *)scrolled_window, GTK_SHADOW_IN);
gtk_scrolled_window_set_policy((GtkScrolledWindow *)scrolled_window, GTK_POLICY_AUTOMATIC, GTK_POLICY_AUTOMATIC);
gtk_box_pack_start((GtkBox *) (GtkDialog *) (gtk_dialog_get_content_area(window)), scrolled_window, TRUE, TRUE, 0);
gtk_widget_show(scrolled_window);
label=gtk_label_new(text);
gtk_label_set_use_markup((GtkLabel *)label, TRUE);
gtk_label_set_selectable((GtkLabel *)label, TRUE);
gtk_label_set_line_wrap((GtkLabel *)label, FALSE);
gtk_container_add((GtkContainer *)scrolled_window, label);
gtk_widget_show(label);
button=gtk_dialog_add_button((GtkDialog *)window, "close", GTK_RESPONSE_CLOSE);
g_signal_connect_swapped(button, "response", (GCallback *)gtk_widget_destroy, window);
gtk_widget_set_can_default(button, TRUE);
gtk_widget_grab_default(button);
gtk_widget_show(button);
gtk_widget_show(window);
gtk_dialog_run((GtkDialog*)window);
gtk_widget_destroy(window);
For the top section you gtk_dialog_get_content_area. This will return a VBox, where you can pack your own widgets.
For the bottom section you either gtk_dialog_add_button or gtk_dialog_add_action_widget.
The GtkDialog contains only private fields and should not be directly accessed.
If you want to add a non-activatable widget, simply pack it into the action_area field of the GtkDialog struct.
You should obtain a pointer to action_area with deprecated (!)gtk_dialog_get_action_area, but that will not allow to register a response id.

Change text color of label in GTK in C

I am using Gtk 2.0.
I am trying to change the text color/font color of the label.
How difficult can it get? I am just trying things like gtk_widget_modify_text etc to no avail. I want to go the "android" or "Qt" way by say adding a simple resource file with all the styles. Where and as what(.rc?) should I add this file? How to parse this file?
I already wrote my App with a lot of widgets and I do not want to change/redo them all. Can somebody show me a simple example?
I even tried a Pango example from the web but the problem is the text in my label keeps changing and therefore I could not follow this.
Please help. Here is what I have tried so far and without success.
GtkWidget *label1;
label1= gtk_label_new(" ");
gtk_box_pack_start (GTK_BOX(box1), label1,TRUE,TRUE, 0);
GdkColor color;
gdk_color_parse ("white", &color);
gtk_widget_modify_text ( GTK_WIDGET(label1), GTK_STATE_NORMAL, &color);
gchar *stringMarkupText = "<span foreground=\"white\"> <b>Bold</b></span>"; //white color and bold--> the length of this text is fixed by number of spaces. I need to call a function that would set this text on a g_signal_connect so do not want to fix spaces!!
gchar *stringPlainText;
PangoAttrList *attrList;
pango_parse_markup(stringMarkupText, -1, 0, &attrList, &stringPlainText, NULL, NULL);
gtk_label_set_attributes(GTK_LABEL(label1), attrList);
From my point of view, you may use GTK resource file(rc file) in this case.
You can use the gtk_rc_parse function to load your rc file.
void gtk_rc_parse(const gchar *filename);

c - Passing multiple arguments to a callback function in GTK

So, I'm trying to achieve the following: The user shall be able to fill out multiple gtk_entry's and click Apply after that, on being clicked I want the Apply button to emit a signal, something like this:
g_signal_connect (G_OBJECT (Apply), "clicked",
G_CALLBACK(apply_clicked), # an argument #);
Afterwards, in apply_clicked(), I want the entered text to be saved.
My question is: How do I pass those gtk_entry's to my callback function apply_clicked?
If it were only one I'd just set it as # an argument #, but what should I do with multiple entries ?
The typical way of doing this is to do:
g_object_set_data (context_object, "entry1", entry1);
g_object_set_data (context_object, "entry2", entry2);
g_signal_connect (G_OBJECT (Apply), "clicked", G_CALLBACK (apply_clicked), context_object);
and then in apply_clicked:
GtkEntry *entry1 = g_object_get_data (context_object, "entry1");
...
Usually the context_object will be the GtkDialog or whatever these widgets exist on.
Alternatively, if you subclass the GtkDialog, you can do:
struct _MyDialog {
GtkDialog parent_object;
GtkEntry *entry1;
GtkEntry *entry2;
...
};
Then, when constructing your dialog, just set entry1, 2, 3, etc... and you don't need to use the g_object_[g,s]et_data() hack.
create a data structure (a linked list perhaps) to contain pointers to the gtk_entrys and pass that instead. Or better yet, why not just pass a pointer to the object which contains all of thise gtk_entrys?

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