use strict;
use warnings;
use Wx qw(:everything);
my ($window, $entry, $display_field);
package MyApp;
use base 'Wx::App';
use Wx qw(:everything);
sub OnInit { 
 
 $window = Wx::Frame->new(
  undef,
  -1,
  '',
  [0,0],
  [520,580],
 );  
 $entry = Wx::TextCtrl->new(
           $window,    
           -1,         
           "",     
           [0, 0], 
     [408,-1],
 ); 
 
 my $button = Wx::Button->new(
  $window,
  -1,
  "Search",  
  [428,0],    
    );  
 $display_field = Wx::TextCtrl->new(
           $window,           
           -1,              
           "",     
           [0, 30],        
     [508,513],
     wxTE_MULTILINE,
   );
  
    Wx::Event::EVT_BUTTON( $button, -1, \&button_click,); 
 
 sub button_click {
  my $now = time;

  #text file encoded in GB2312 about the size of 30 MB...
  #containing English and Chinese characters
  my $file = "./data"; 
  open my $data, '<', $file or die "Open failed: $!";  
  $display_field->Clear;  
  $display_field->Update;  
  my $query = $entry->GetValue(); 
  while(<$data>){   
   if(/$query/i){
    $display_field->AppendText($_);
    $window->Update;     
            }
  }
  $now = time - $now;
  my $time = sprintf("\n\nTotal running time: %02d:%02d:%02d\n\n", int($now / 3600),
   int(($now % 3600) / 60), int($now % 60));
  $display_field->AppendText($time);
          
 }
 
 $window->Show;
 
}
MyApp->new->MainLoop;