In my program, I have a section of code that updates a list box depending on the value of another list box.
The code that does this looks a little like this.
$listBox1->bind('<<ListboxSelect>>' => sub {
$listBox2->delete(0, 'end');
for(@{$hashOfArraysOfStruct{$listBox1->get($listBox1->curselection)}}) {
$listBox2->insert('end', $_->name);
}
});
This works fine. However, I have found it easier to simply use a list and manipulate the list on the <<ListboxSelect>>
. I have bound this list to the list box using -listvariable
.
The code to do this looks a bit like
$listBox1->bind('<<ListboxSelect>>' => sub {
@updateableList = @{$hashOfArraysOfStruct{$listBox1->get($listBox1->curselection)}};
});
The problem with this approach is, as hashOfArraysOfStruct
, contains structures, the list box contains values such as MyStruct=HASH(0x31d7e3c)
.
Is there any way to display the name
variable of the struct MyStruct
without looping through the whole array and individually inserting each result into the list box?
MCVE
use strict;
use warnings;
use Tk;
use Class::Struct;
struct MyStruct => {
name => '$',
group => '$'
};
my %hashOfArraysOfStruct = (
A => [
MyStruct->new(name => 'Phil', group => 'A'),
MyStruct->new(name => 'Ian', group => 'A'),
MyStruct->new(name => 'George', group => 'A')
],
B => [
MyStruct->new(name => 'Mac', group => 'B'),
MyStruct->new(name => 'Will', group => 'B')
],
C => [
MyStruct->new(name => 'Cath', group => 'C'),
MyStruct->new(name => 'Thom', group => 'C'),
MyStruct->new(name => 'Richard', group => 'C'),
MyStruct->new(name => 'Paul', group => 'C'),
MyStruct->new(name => 'Nick', group => 'C')
]
);
my $mainWindow = MainWindow->new();
my @listOne = sort(keys %hashOfArraysOfStruct);
############################################
#Route One
#Less efficient as has to loop through all the values
#But it displays the name variable of MyStruct
my $listBox1 = $mainWindow->Scrolled("Listbox", -scrollbars => "osoe", -selectmode => "single", -listvariable => \@listOne)->pack;
my $listBox2 = $mainWindow->Scrolled("Listbox", -scrollbars => "osoe", -selectmode => "single")->pack;
$listBox1->bind('<<ListboxSelect>>' => sub {
$listBox2->delete(0, 'end');
for(@{$hashOfArraysOfStruct{$listBox1->get($listBox1->curselection)}}) {
$listBox2->insert('end', $_->name);
}
});
############################################
############################################
#Route Two
#Works but displays in the form of MyStruct=HASH(0x31d7e3c)
#my @updateableList;
#my $listBox1 = $mainWindow->Scrolled("Listbox", -scrollbars => "osoe", -selectmode => "single", -listvariable => \@listOne)->pack;
#my $listBox2 = $mainWindow->Scrolled("Listbox", -scrollbars => "osoe", -selectmode => "single", -listvariable => \@updateableList)->pack;
#$listBox1->bind('<<ListboxSelect>>' => sub {
# @updateableList = @{$hashOfArraysOfStruct{$listBox1->get($listBox1->curselection)}};
#});
############################################
############################################
#What I would like to happen
#I would like to use route two but when the struct is displayed
#in the list box, instead of being in Route Twos format, it should
#display the name variable of MyStruct.
############################################
MainLoop;
Massive Edit
Change
to
To extract the list of names from the list of structs;