GTK+ Forums

Jamiil · Familiar Face Joined: 22 Sep 2005 Posts: 20

Assignment operator for GtkWidgets?

Is there such a thing, can we do things like MyGtkWidget = SomeGtkWidget?

I get a segmentation fault when I try todo that!

What am I doing wrong?

class Data{
public:
std::string str;
GtkWidget* obj;
public:
Data(){str = "";}
void setStr(std::string ps){ str = ps;}
void setObj(GtkWidget* o){obj = o;}
};

//Declare the objects
GtkWidget* MainMenueWin;
GtkWidget* VBx;
GtkWidget* Label;
GtkWidget* Separator;
GtkWidget* btnExit;
GtkWidget* btnCreateAccount;
GtkWidget* btn2;
GtkWidget* btn3;
GtkWidget* btn4;
GtkWidget* btn5;
Data* data;
std::string msg("Under Comstruction ... I am very sorry, but this \
feature has not been implemented yet. Please \
email me for any new updates on this program \
puchica@hotmail.com");

//Callbacks

void Quit(GtkButton* , gpointer);
gboolean SystemQuit(GtkWidget*, GdkEvent*, gpointer);

void Quit(GtkButton* was_clicked, gpointer user_data){
gtk_main_quit();
}
gboolean SystemQuit(GtkWidget* widget, GdkEvent* event, gpointer user_data){
gtk_widget_destroy(widget);
gtk_main_quit();
return(TRUE);
//return(FALSE);
}

int main(int argc, char *argv[]){
// 1. Initialize the environment
gtk_set_locale ();
gtk_init(&argc, &argv);
//-liconv -liconv
// 2. Create Widgets
MainMenueWin = gtk_window_new(GTK_WINDOW_TOPLEVEL);
//gtk_window_new(GTK_WINDOW_TOPLEVEL);
VBx = gtk_vbox_new(FALSE,10);
Label = gtk_label_new("Jaime");
Separator = gtk_hseparator_new();
btnCreateAccount = gtk_button_new_with_label("Create");
btn2 = gtk_button_new_with_label("Unknown");
btn3 = gtk_button_new_with_label("Unknown");
btn4 = gtk_button_new_with_label("Unknown");
btn5 = gtk_button_new_with_label("Unknown");
btnExit = gtk_button_new_with_label("Exit");
// Information for GeneralMessage

data->setObj(MainMenueWin);
data->setStr(msg);

// 3. Set attributs
gtk_window_set_title(GTK_WINDOW(MainMenueWin), "Jaime");
gtk_window_set_policy(GTK_WINDOW(MainMenueWin), //which_window
FALSE, // allow_shrink
FALSE, // allow_grow
FALSE); // auto_shrink

gtk_container_set_border_width(GTK_CONTAINER(MainMenueWin),15);
gtk_widget_set_name(MainMenueWin,"Gtk++ One, dos");
gtk_widget_set_name(VBx,"vertical box");
gtk_widget_set_name(Label,"Label");
gtk_widget_set_name(Separator, "Separator");

// 4. Register CallBacks
// These three callback fun' are only to exit the application
g_signal_connect( GTK_OBJECT(btnExit), "clicked",
G_CALLBACK(Quit), NULL);
g_signal_connect( GTK_OBJECT(MainMenueWin), "delete-event",
GTK_SIGNAL_FUNC(SystemQuit), NULL);
g_signal_connect(GTK_OBJECT(MainMenueWin), "destroy",
G_CALLBACK(SystemQuit), NULL);

g_signal_connect(GTK_OBJECT(btnCreateAccount), "clicked",
G_CALLBACK(GeneralMsg), reinterpret_cast<gpointer>(&data));

g_signal_connect(GTK_OBJECT(btn2), "clicked",
G_CALLBACK(GeneralMsg), reinterpret_cast<gpointer>(&data));
g_signal_connect(GTK_OBJECT(btn3), "clicked",
G_CALLBACK(GeneralMsg), reinterpret_cast<gpointer>(&data));
g_signal_connect(GTK_OBJECT(btn4), "clicked",
G_CALLBACK(GeneralMsg), reinterpret_cast<gpointer>(&data));
g_signal_connect(GTK_OBJECT(btn5), "clicked",
G_CALLBACK(GeneralMsg), reinterpret_cast<gpointer>(&data));

// 5. Define instance hirarchy (pack the widgets)
gtk_container_add(GTK_CONTAINER(MainMenueWin), VBx);
gtk_box_pack_start_defaults(GTK_BOX(VBx), Label);
gtk_box_pack_start(GTK_BOX(VBx), btnCreateAccount, FALSE, FALSE,1);
gtk_box_pack_start(GTK_BOX(VBx), btn2, FALSE, FALSE,1);
gtk_box_pack_start(GTK_BOX(VBx), btn3, FALSE, FALSE,1);
gtk_box_pack_start(GTK_BOX(VBx), btn4, FALSE, FALSE,1);
gtk_box_pack_start(GTK_BOX(VBx), btn5, FALSE, FALSE,1);

gtk_box_pack_start(GTK_BOX(VBx), Separator, FALSE,FALSE, 1);
gtk_box_pack_start_defaults(GTK_BOX(VBx), btnExit);

// 6. Show the Widgets
gtk_widget_show_all(MainMenueWin);

// 7. Processing loop
gtk_main();
//if (data) { delete data; }
std::cerr << "Assalam Alaykum" << std::endl;
return 0;
}

void GeneralMsg(GtkButton* button, gpointer p) {
Data* d;
GtkWidget* label;
GtkWidget* dialog;

try {
dialog = new GtkWidget;
label = new GtkWidget;
d = new Data();
} catch(std::exception& e) { std::cout << e.what() << std::endl;}
try{d = reinterpret_cast<Data*>(p);}
catch(std::exception& e){std::cerr << e.what() << std::endl;}
dialog = gtk_message_dialog_new(
einterpret_cast<GtkWindow*>(d->obj), //Parent
static_cast<GtkDialogFlags>(GTK_DIALOG_MODAL |
GTK_DIALOG_DESTROY_WITH_PARENT), //Flags
reinterpret_cast<GtkMessageType>(GTK_MESSAGE_WARNING), // Message type
reinterpret_cast<GtkButtonsType>(GTK_BUTTONS_OK), //Button type
d->str.c_str()); //Message format

// Destroy the dialog when the user responds to it (e.g. clicks a button)

gtk_dialog_run (GTK_DIALOG (dialog));
gtk_widget_destroy (dialog);

delete d;
delete dialog;
delete label;
}

openldev · Posted: Mon Sep 26, 2005 9:55 pm Post subject:

You declared Data *data, but never initialized it. Right now it's just a pointer without love. You have to do "data = new Data();" to give it love...

Sorry for my stupidity, but I'm very tired...

Jamiil · Familiar Face Joined: 22 Sep 2005 Posts: 20

In the constructor I assigned values to the two variables,
namespace jme{
class Data{
public:
std::string str;
GtkWidget* obj;
public:
Data(){str = ""; obj = gtk_window_new(GTK_WINDOW_TOPLEVEL);}
void setStr(std::string ps){ str = ps;}
void setObj(GtkWidget* o){obj = o;}
};
}
and as soon as I get the value for the jme::Data::str variable, I replace the value, but for jme::Data::obj, I replace the value as soon as the GtkWidget::MainMenuWin value is aquired.

But, for some reason, I am unable to use the assignment operator on GtkWidget objects.

What should I do now?