When I attach a menu to a window I detach the existing root control, add a vertical GtkBox to hold the menu and the root control and then attach that box to the GtkWindow, like so:
Gtk::GtkWidget *menubar = GTK_WIDGET(Info.obj);
Wnd->_VBox = Gtk::gtk_box_new(Gtk::GTK_ORIENTATION_VERTICAL, 0);
Gtk::GtkBox *vbox = GTK_BOX(Wnd->_VBox);
Gtk::GtkContainer *wndcontainer = GTK_CONTAINER(Wnd->Wnd);
g_object_ref(Wnd->_Root);
gtk_container_remove(wndcontainer, Wnd->_Root);
gtk_box_pack_start(vbox, menubar, false, false, 0);
gtk_box_pack_end(vbox, Wnd->_Root, true, true, 0);
gtk_container_add(wndcontainer, Wnd->_VBox);
gtk_widget_show_all(GTK_WIDGET(Wnd->Wnd));
g_object_unref(Wnd->_Root);
gtk_window_add_accel_group(Wnd->Wnd, AccelGrp);
In practice it looks like this:
What I'd like is the menu to appear in the correct place automatically without having to resize the window to force a layout update.
I've tried calling gtk_widget_queue_draw on the window but that made no difference. Am I doing something wrong here? Can a call an extra function to invalidate the layout and get it to refresh?
It's difficult to answer without having a minimal reproducible example. Your code in not even plain GTK or gtkmm... it seems to be some exotic variant between the two.
Here is my attempt: I tried to be as close as possible to your code. The issue you are describing is not present though.
/* gcc -o test test.c $(pkg-config --cflags --libs gtk+-3.0) */
#include <gtk/gtk.h>
static GMenu *
menu_model(void)
{
GMenu *menu = g_menu_new();
g_menu_append(menu, "File", NULL);
g_menu_append(menu, "Edit", NULL);
g_menu_append(menu, "Project", NULL);
/* ... */
return menu;
}
int main(int argc, char **argv)
{
GtkWidget *window;
GMenuModel *model;
GtkWidget *menubar;
GtkWidget *content;
GtkWidget *vbox;
gtk_init(&argc, &argv);
window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
model = G_MENU_MODEL(menu_model());
menubar = gtk_menu_bar_new_from_model(model);
g_object_unref(model);
content = gtk_label_new("Some content here");
vbox = gtk_box_new(GTK_ORIENTATION_VERTICAL, 0);
gtk_box_pack_start(GTK_BOX(vbox), menubar, FALSE, FALSE, 0);
gtk_box_pack_end(GTK_BOX(vbox), content, TRUE, TRUE, 0);
gtk_container_add(GTK_CONTAINER(window), vbox);
gtk_widget_show_all(GTK_WIDGET(window));
gtk_main();
return 0;
}
So while it should "just work" out of the box. And indeed on my Raspberry Pi the code does just do what it's supposed to do, this is still an issue on my Ubuntu 18 VM. I have found somewhat of a work around to kick the GtkBox into reconfiguring the child widget's layout:
GdkRectangle allocation = Wnd->GetClient();
g_signal_emit_by_name(G_OBJECT(vbox), "size-allocate", GTK_WIDGET(vbox), &allocation, NULL, NULL);
The menu now appears in the right location automatically. It seems like a "hack" that may stop working in the future or crash on some systems? IDK. But in terms of right now and Ubuntu 18, I don't have anything better.
Related
Gtk3 in C: I am trying to create a window that loads a picture from a png/jpeg file. I want the user to be able to resize the window and automatically scale the picture to fit the window.
So here is what I do:
app = gtk_application_new("foo", G_APPLICATION_FLAGS_NONE);
g_signal_connect(app, "activate", G_CALLBACK(activate), NULL);
status = g_application_run(G_APPLICATION(app), argc, argv);
then the activate method does:
GtkWidget *window;
window = gtk_application_window_new(app);
gtk_window_set_title(GTK_WINDOW(window), "foo");
gtk_window_set_default_size(GTK_WINDOW(window), 600, 600);
GError *err = NULL;
// Note: original and image are global variables, because I can't
// get user_data for callbacks working. Will sort this out later.
original = gdk_pixbuf_new_from_file("myfile.png", &err);
if (err != NULL) {
fatalf(scope, "Unable to read file: %s\n", err->message);
exit(1);
}
image = gtk_image_new();
gtk_container_add(GTK_CONTAINER(window), image);
gtk_widget_show_all(window);
g_signal_connect(G_OBJECT(window), "configure-event", G_CALLBACK(resize_picture), NULL);
and the resize_picture:
gint w, h;
gtk_window_get_size(window, &w, &h);
GdkPixbuf *resized = gdk_pixbuf_scale_simple(original, w, h, GDK_INTERP_BILINEAR);
gtk_image_set_from_pixbuf(image, resized);
Now the problem is that the GtkImage appears to impose the minimum size on the window. I can enlarge the window, which scales up the picture, but I cannot shrink it. Is there some property I can set on GtkWindow or GtkImage to allow me to do that? Or do I need to use something else than GtkImage?
The solution is to switch to GTK4 and use GtkPicture instead of GtkImage.
GtkPicture has can_shrink property, which solves this problem.
I'm totally in trouble. Wanna set maximum width of progressbar, but the only thing I found is min- properties, that can be set through CSS. What else can I do?
As you probably have found out through research, the CSS "max-width" property is not a property currently handled via the GTK CSS provider. In testing out various scenarios with a progress bar, it seems that the constricting factor is the width allowances of the various GTK containers. And, the only container that appeared to allow for adjusting the width of a progress bar was within a "GtkBox" container. Following is a minimal program I composed to test out various widths for a progress bar (FYI, this is GTK3).
#include <gtk/gtk.h>
int main (int argc, char *argv[])
{
GtkWidget *prog = NULL;
GtkWidget *win = NULL;
GtkWidget *box = NULL;
gtk_init (&argc, &argv);
win = gtk_window_new (GTK_WINDOW_TOPLEVEL);
box = gtk_box_new(GTK_ORIENTATION_HORIZONTAL, 2);
prog = gtk_progress_bar_new();
gtk_window_set_title (GTK_WINDOW (win), "Progress Max");
gtk_container_set_border_width (GTK_CONTAINER (win), 20);
gtk_window_set_default_size(GTK_WINDOW(win), 400, 120);
g_signal_connect (win, "destroy", gtk_main_quit, NULL);
gtk_container_add (GTK_CONTAINER (win), box);
gtk_widget_set_size_request(prog, 200, 20); /* Vary the length to test the effect */
gtk_box_pack_start(GTK_BOX(box), prog, FALSE, TRUE, 40);
gtk_widget_show_all (win);
gtk_main ();
return 0;
}
Make note of the size values in the "gtk_widget_set_size_request" function to determine your progress bar width, and note the boolean values for the "fill" and "padding" parameters in the "gtk_box_pack_start" function. I believe that if you experiment with those statements that you should be able to control the desired width of your progress bar.
Regards.
I'm trying to popup an OK message box in my gtk browser, but all I'm getting is blank grey square patch without my text in it and even button is not visible.
PFB the function which I'm using to render message box :
Void DisplayOKPopup()
{
dialogue=gtk_message_dialogue_new(GTK_WINDOW(WebtBrowserWindow),
GTK_DIALOGUE_DESTROY_WITH_PARENT,
GTK_MESSAGE_INFO,
GTK_BUTTONS_OK,
"text message");
gtk_widget_show(dialogue);
LOGDEBUG(" 1");
gtk_dialogue_run(GTK_DIALOGUE (dialogue));
LOGDEBUG("2");
gtk_widget_destroy (dialogue);
}
As per my debug log, I can see that control is passing till LOGDEBUG("1") and after that it goes to gtk_dialogue_run after that UI is getting crashed, the line next to run i.e LOGDEBUG("2") is not getting executed.
Kindly provide your inputs as I'm working on this since 3 days:!
As concluded, the problem arises from the use of threads. There are several approaches to solve the issue but since there is not code, I'll try with a simple example so that you can recreate it on your code.
Take a global Boolean variable as a flag and on your thread, set it to true so that a "periodic" idle callback can check it and if the flag is TRUE then show the dialog. The logic is that the Gtk UI functions are called from the mainloop/main thread and not from the worker threads.
DisplayOkPopup just has a simple "counter" from 0 to MAX_INT (32 bits) and set's the global flag as TRUE.
check_for_dialog it's a callback that runs on mainloop idle time and check for the flag, if TRUE then runs the dialog.
exit is dirty and will output errors but the goal ain't that, its just a tip/hint for your solution.
Example:
#include <gtk/gtk.h>
gboolean dialog_active;
gboolean show_dialog_popup;
GtkWidget *window;
gpointer DisplayOKPopup (gpointer user_data) {
int i;
while (TRUE) {
for (i = 0; i < G_MAXINT32; i++) {
// nop
}
show_dialog_popup = TRUE;
}
return NULL;
}
gboolean check_for_dialog (gpointer user_data) {
if (show_dialog_popup == TRUE && dialog_active == FALSE) {
dialog_active = TRUE;
GtkWidget *dialog = gtk_message_dialog_new(GTK_WINDOW(window),
GTK_DIALOG_DESTROY_WITH_PARENT,
GTK_MESSAGE_INFO,
GTK_BUTTONS_OK,
"text message");
gtk_dialog_run(GTK_DIALOG (dialog));
show_dialog_popup = FALSE;
dialog_active = FALSE;
gtk_widget_destroy(dialog);
}
return TRUE;
}
static void app_activate(GtkApplication *app, gpointer user_data) {
window = gtk_application_window_new(app);
gtk_window_set_title(GTK_WINDOW(window), "Window Title Here");
gtk_window_set_default_size(GTK_WINDOW(window), 700, 400);
gtk_window_set_position(GTK_WINDOW(window), GTK_WIN_POS_CENTER);
//gtk_container_add(GTK_CONTAINER(window), fixed);
gtk_widget_show_all(window);
g_idle_add(check_for_dialog, NULL);
g_thread_new("my thread", DisplayOKPopup, NULL);
}
int main(int argc, char **argv) {
GtkApplication *app;
int status;
show_dialog_popup = FALSE;
dialog_active = FALSE;
app = gtk_application_new("your.application.id", G_APPLICATION_FLAGS_NONE);
g_signal_connect(app, "activate", G_CALLBACK(app_activate), NULL);
status = g_application_run(G_APPLICATION(app), argc, argv);
g_object_unref(app);
return status;
}
Build and run:
$ gcc -o test test.c `pkg-config --cflags --libs gtk+-3.0`
$ ./test
Result:
EDIT:
Answer to your comment is:
To have custom buttons on your dialog then use:
gtk_dialog_new_with_buttons
gtk_dialog_add_button (if dialog exists, will add 1 button)
gtk_dialog_add_buttons (same as above but can add many buttons)
Example for 1):
dialog = gtk_dialog_new_with_buttons ("My dialog",
main_app_window,
flags,
"_OK",
GTK_RESPONSE_ACCEPT,
"_Cancel",
GTK_RESPONSE_REJECT,
NULL);
Example for 2):
gtk_dialog_add_button (GTK_DIALOG(dialog),
"This is my button",
GTK_RESPONSE_ACCEPT);
Example for 3) is same as 2) but can handle many buttons and terminates with NULL.
I use a goocanvas and use signals for mouse events connected to some graphical items. If I use a dialog from a signal handler, all signals are broken after closing the dialog. Is this a bug of gtkmm/goocanvas or is this some kind of misuse in my program?
The wrong behavior is:
You can click somewhere in the canvas area, nothing is happen which is correct. If you click on the circle the signal handler starts the dialog which is also expected. After closing the dialog ( OK button ) you can click somewhere on the canvas and the signal handler is called which is wrong.
In my real program the signal handlers are sometimes never called and sometimes called on wrong areas and so on. A bit strange behavior. I hope someone can find the problem.
#include <gtkmm.h>
#include <goocanvasmm.h>
#include <sigc++/sigc++.h>
bool ShowDialog( const Glib::RefPtr<Goocanvas::Item>& item, GdkEventButton* ev)
{
enum { OK };
Gtk::Dialog dialog;
dialog.add_button( Gtk::Stock::OK, OK);
dialog.show_all_children();
dialog.run();
return false;
}
int main(int argc, char* argv[])
{
Gtk::Main app(&argc, &argv);
Goocanvas::init("example", "0.1", argc, argv);
Gtk::Window win;
Goocanvas::Canvas m_canvas;
m_canvas.set_size_request(640, 480);
m_canvas.set_bounds(0, 0, 800, 800);
Glib::RefPtr<Goocanvas::Item> root = m_canvas.get_root_item();
Glib::RefPtr<Goocanvas::Ellipse> outer = Goocanvas::Ellipse::create( 100,100,20,20);
outer->property_line_width() = 5;
outer->property_stroke_color() = "red";
outer->property_fill_color()="blue";
root->add_child( outer );
sigc::connection conn2= outer->signal_button_press_event().connect( sigc::ptr_fun(&ShowDialog));
win.add(m_canvas);
win.show_all_children();
Gtk::Main::run(win);
return 0;
}
I think I've got an understanding problem of GTK. My simple application has a stream of images and I'd like to display them within my GTK Window. Up to now, it looks like this:
GdkPixbuf *pb = gdk_pixbuf_new_from_data(img2, GDK_COLORSPACE_RGB,
FALSE, 24/3, 320, 240, 320*3,
NULL, NULL);
if(pb == NULL)
fprintf(stderr, "Pixbuf is null!\n");
if(image != NULL)
gtk_container_remove(GTK_CONTAINER(window), image);
image = gtk_image_new_from_pixbuf(pb);
gtk_container_add(GTK_CONTAINER(window), image);
printf("Updated!\n");
img2 is my (rgb) buffer that gets updated from a stream each time. I guess gtk_container_remove and gtk_container_add might be stupid to use for this?
Here's what I've got in addition:
GtkWidget *window;
GtkWidget *image;
gtk_init(&argc, &argv);
window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
gtk_signal_connect(GTK_OBJECT(window), "destroy",
GTK_SIGNAL_FUNC(destroy), NULL);
/* ... */
start_routine_for_stream_that_calls_the_above(...)
/* ... */
gtk_widget_show_all(window);
gtk_main();
My problem is that it's not working this way... either I see only the last GdkPixbuf image or I see none, which is the correct behaviour ...
But how do I manage it to show an (stream of) updated GdkPixbuf?
Thanks for help
You need to be running the main loop while you change the images. For instance, you can do gtk_main() and use g_timeout_add() to schedule your callback to run say every second and replace images within that callback.