in reply to Making a TK GUI in a thread

Unless a package is reported as thread safe you must assume it is not thread safe. As such, you cannot use Tk outside your sub. The following works fine (no free to wrong pool errors). 
#!/usr/bin/perl -w

use strict;
use threads;

# Create main window
sub gui {
    require Tk;
    my $main = MainWindow->new;

# Add a Label and a Button to main window
    $main->Label(-text => 'Hello, world!')->pack;
    $main->Button(-text => 'Quit',
        -command => [ $main => 'destroy']
    )->pack;

# Spin the message loop
    Tk->MainLoop;
}

my $server_thread = threads->create("gui");

while (1) {
    sleep(1);
    print "cav\n";
}

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Seeing how the above works, I believe Tk would be considered thread friendly. You may wish to consider using Thread::Use.

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MJD says "you can't just make shit up and expect the computer to know what you mean, retardo!"
I run a Win32 PPM repository for perl 5.6.x and 5.8.x -- I take requests (README).
** The third rule of perl club is a statement of fact: pod is sexy.

Replies are listed 'Best First'.
Re: Re: Making a TK GUI in a thread
by cavalive (Novice) on Sep 19, 2003 at 04:00 UTC
    Thanks for the help... actualy I continue to have problems... what I really wanted to do was display a loading screen while my program did its various
    operations, then finally display the main gui. My plan was showing an initial gui, loading the stuff, destroying
    the gui and loading the final gui, but I continue to get
    spool errors... check it out

    use strict;
    use Thread::Use;
    use threads;
    use threads::shared;
    my $u; share ($u);

    my $load_gui = threads->create("loading_screen");

    my $counter;

    #Simulate program loading
    while ($counter < 3) {
    sleep($counter);
    $counter++;
    }
    $u = 1;#destroy loading screen
    $load_gui->join;

    #Load the final gui
    my $load_gui2 = threads->create("loadGui");

    #keep program fom ending
    while (1) {
    sleep(1);
    print "cav\n";
    }


    ##GUIS###########################

    sub loading_screen {
    useit Tk;
    my $main = MainWindow->new;
    $main->repeat(100 => sub {if ($u){$main->destroy}});

    # Add a Label and a Button to main window
    $main->Label(-text => 'Loading!')->pack;
    Tk->MainLoop;
    }

    sub loadGui {
    useit Tk;
    my $main = MainWindow->new;

    # Add a Label and a Button to main window
    $main->Label(-text => 'Main Gui')->pack;

    # Spin the message loop
    Tk->MainLoop;
    }
[reply]
      You don't need threads to throw up a splash screen. See Tk::Splashscreen - display a Splashscreen during program initialization.

      MJD says "you can't just make shit up and expect the computer to know what you mean, retardo!"
      I run a Win32 PPM repository for perl 5.6.x and 5.8.x -- I take requests (README).
      ** The third rule of perl club is a statement of fact: pod is sexy.

[reply]

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