Dear all. I use the following code to force a default value for the entry if the input value is rejected by -validatecommand. 
use strict;
use Tk;
my $xVConsSflEmbMax0 = 1.0;
my $xVConsSflEmbMax = $xVConsSflEmbMax0;
    my $emb1Entry = $embCanvas->Entry(
      -textvariable     => \$xVConsSflEmbMax,
      -width            => 3,
      -validate         => 'focusout',
      -validatecommand  => sub {$_[0] =~ /^\d*\.?\d+$/},
      -invalidcommand   => sub {$xVConsSflEmbMax=$xVConsSflEmbMax0},
    );

[download]
It works fine but only once! If the user tries to modify the entry a second time with a wrong input the validate command is ineffective. Would you have any advice to make it work? Thanks a lot

In reply to perl/Tk Entry validation by Anonymous Monk

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