# Using TkEntry with copy/paste

**URL:** <https://www.ruby-forum.com/t/using-tkentry-with-copy-paste/189763>\
**Category:** Ruby\
**Created:** [June 7, 2010, 11:26am UTC](https://www.ruby-forum.com/t/using-tkentry-with-copy-paste/189763 "2010-06-07T11:26:02Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![kookjr](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/df788c/32.png) [@kookjr](https://www.ruby-forum.com/u/kookjr)\
**Post date:** [June 7, 2010, 11:26am UTC](https://www.ruby-forum.com/t/using-tkentry-with-copy-paste/189763/1 "2010-06-07T11:26:02Z")

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I’m writing a Ruby/Tk program where I want a TkEntry field with a  
state of “readonly” so a user can copy/paste from it, but not modify  
it. Unfortunately this prevents me from programatically changing it,  
which I want to do. Is there a better way to accomplish that?

Sample code: TkEntry does not display “hi” after button click.

`
require 'tk'
top = TkRoot.new
entry = TkEntry.new(top) {state "readonly";grid('row'=>0, 'column'=>0)}
TkButton.new(top) {text ‘Convert’; grid(‘row’=>1, ‘column’=>0);
the “entry” field update fails, as documented
command proc {entry.value = “hi”}
}
Tk.mainloop
Environment
Ubuntu 10.4
2.6.32-22-generic #36-Ubuntu SMP Thu Jun 3 22:02:19 UTC 2010
i686 GNU/Linux
ruby 1.8.7 (2010-01-10 patchlevel 249) [i486-linux]
libtcltk-ruby
libtcltk-ruby1.8
`

Thanks,  
Mathew C.

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**Author:** ![kookjr](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/df788c/32.png) [@kookjr](https://www.ruby-forum.com/u/kookjr)\
**Post date:** [June 7, 2010, 12:23pm UTC](https://www.ruby-forum.com/t/using-tkentry-with-copy-paste/189763/2 "2010-06-07T12:23:58Z")

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From: Mathew C. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
Subject: using TkEntry with copy/paste  
Date: Mon, 7 Jun 2010 18:26:05 +0900  
Message-ID: [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)

> I’m writing a Ruby/Tk program where I want a TkEntry field with a  
> state of “readonly” so a user can copy/paste from it, but not modify  
> it. Unfortunately this prevents me from programatically changing it,  
> which I want to do. Is there a better way to accomplish that?

How about the following

`
require 'tk'
top = TkRoot.new
var = TkVariable.new
entry = TkEntry.new(top, :state=>'readonly',
                         :textvariable=>var).grid(:row=>0, :column=>0)
TkButton.new(top, :text=>'Convert',
                  :command=>proc{var.value = 'hi'}).grid(:row=>1, 
:column=>0)
`

`Tk.mainloop
`

---

<div class="post-metadata">

**Author:** ![kookjr](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/df788c/32.png) [@kookjr](https://www.ruby-forum.com/u/kookjr)\
**Post date:** [June 7, 2010, 6:33pm UTC](https://www.ruby-forum.com/t/using-tkentry-with-copy-paste/189763/3 "2010-06-07T18:33:39Z")

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Hidetoshi NAGAI wrote:

> How about the following
> 
> `
> require 'tk'
> top = TkRoot.new
> var = TkVariable.new
> entry = TkEntry.new(top, :state=>'readonly',
> :textvariable=>var).grid(:row=>0, :column=>0)
> TkButton.new(top, :text=>'Convert',
> :command=>proc{var.value = 'hi'}).grid(:row=>1, 
> :column=>0)
> Tk.mainloop
> `

Thanks, that will work. I tried what I thought was the equivalent  
(below) but it didn’t work. The only real difference was that I  
didn’t pass my config params as function arguments.

`
require 'tk'
top = TkRoot.new
variable used in entry field, written with button press
text_var = TkVariable.new
entry = TkEntry.new(top) {textvariable = text_var; grid(‘row’=>0,
‘column’=>0)}
TkButton.new(top) {text ‘Convert’; grid(‘row’=>1, ‘column’=>0);
command proc {
# the next line does not show the string in the TkEntry
text_var.value = “using variable”
}
}
`

---

<div class="post-metadata">

**Author:** ![kookjr](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/df788c/32.png) [@kookjr](https://www.ruby-forum.com/u/kookjr)\
**Post date:** [June 8, 2010, 5:07am UTC](https://www.ruby-forum.com/t/using-tkentry-with-copy-paste/189763/4 "2010-06-08T05:07:42Z")

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Hidetoshi NAGAI wrote:

> You define a local variable.  
> Please use “textvariable text\_var” or “self.textvariable = text\_var”.

Thanks, that fixed it.

---

<div class="post-metadata">

**Author:** ![kookjr](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/df788c/32.png) [@kookjr](https://www.ruby-forum.com/u/kookjr)\
**Post date:** [June 7, 2010, 11:17pm UTC](https://www.ruby-forum.com/t/using-tkentry-with-copy-paste/189763/5 "2010-06-07T23:17:23Z")

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From: Mathew C. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
Subject: Re: using TkEntry with copy/paste  
Date: Tue, 8 Jun 2010 01:33:41 +0900  
Message-ID: [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)

> Thanks, that will work. I tried what I thought was the equivalent  
> (below) but it didn’t work. The only real difference was that I  
> didn’t pass my config params as function arguments.  
> (snip)  
> entry = TkEntry.new(top) {textvariable = text\_var; grid(‘row’=\>0,  
> ^^^^^^^^^^^^^^^^^^^^^^^  
> You define a local variable.  
> Please use “textvariable text\_var” or “self.textvariable = text\_var”.