[Lazarus] Gtk3 - Set entry placeholder

[zeljko]

On 01/05/2015 08:37 PM, Krzysztof wrote:
> Hi,
>
> I'm testing Gtk3 (I know that it is in alpha stage). I have latest
> lazarus from svn (1.3)
>
> When using low level Gtk3 api then this code work fine:
>
> uses
>    {$IFDEF UNIX}{$IFDEF UseCThreads}
>    cthreads,
>    {$ENDIF}{$ENDIF}
>    Interfaces, // this includes the LCL widgetset
>    LazGtk3, LazGObject2;
>
> {$R *.res}
>
> var
>    window: PGtkWindow;
>    entry1, entry2: PGtkWidget;
>    vbox: PGtkWidget;
>
> begin
>    gtk_init (@argc, @argv);
>
>    window := gtk_window_new (GTK_WINDOW_TOPLEVEL);
>    gtk_window_set_title (window, 'Window');
>
>    g_signal_connect_data(window, 'destroy', TGCallback(@gtk_main_quit),
> nil, nil, 0);
>
>    vbox := gtk_box_new(GTK_ORIENTATION_VERTICAL, 2);
>    gtk_container_add (PGtkContainer(window), vbox);
>
>    entry1 := gtk_entry_new ();
>    gtk_entry_set_text(PGtkEntry(entry1), 'Hello');
>
>    entry2 := gtk_entry_new ();
>    gtk_entry_set_placeholder_text(PGtkEntry(entry2), '<Test>');
>
>    gtk_box_pack_start(PGtkBox(vbox), entry1, True, True, 0);
>    gtk_box_pack_start(PGtkBox(vbox), entry2, True, True, 0);
>
>    gtk_widget_show_all (window);
>
>    gtk_main ();
> end.
>
> But if I create LCL application, then change LCLWidgetType to Gtk3 and
> call this:
>
> procedure TForm1.Button1Click(Sender: TObject);
> begin
>    gtk_entry_set_placeholder_text(Edit1.Handle), PChar('Test'));

That's because Edit1.Handle is not PGtkEntry, but TGtk3Entry, so this 
code should work (you must include gtk3widgets unit to get it work):
gtk_entry_set_placeholder_text(PGtkEntry(TGtk3Edit(Edit1.Handle).Widget), PChar('Test'));
or
var
   AEntry: PGtkEntry;
begin
   AEntry := PGtkEntry(TGtk3Edit(Edit1.Handle).Widget);
   gtk_entry_set_placeholder_text(AEntry, PChar('Test'));
end;

zeljko