# Basic RubyTk questions

**URL:** <https://www.ruby-forum.com/t/basic-rubytk-questions/112339>\
**Category:** Ruby\
**Created:** [August 17, 2007, 5:45pm UTC](https://www.ruby-forum.com/t/basic-rubytk-questions/112339 "2007-08-17T17:45:49Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![siemsen](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/77aa72/32.png) [@siemsen](https://www.ruby-forum.com/u/siemsen)\
**Post date:** [August 17, 2007, 5:45pm UTC](https://www.ruby-forum.com/t/basic-rubytk-questions/112339/1 "2007-08-17T17:45:49Z")

</div>

I have a Mac OS X system. I wrote a Ruby program that uses RubyTk to  
display a TkLabel. It works, but I’d like a bit more control over how  
it looks. Here’s the code minus the non-Tk stuff that isn’t relevant  
to my questions:

require ‘tk’

answer = ‘test’  
TkLabel.new do  
text answer  
foreground ‘yellow’  
background ‘black’

# place(‘x’ =\> 400, ‘y’ = 400)

pack(‘padx’ =\> 15, ‘pady’ =\> 15)  
end

def timer\_loop3  
exit  
end  
TkAfter.new(3000, # milliseconds  
-1, # ?  
proc{timer\_loop3} # what to call when the timer expires  
).start

Tk.mainloop

The program displays a label for 3 seconds and exits, as intended,  
but…

1. How do I control the placement of the label on the screen? It now  
apppears  
near the upper left-hand corner. I tried “place” (commented out)  
with no  
luck.
2. How can I make the label appear on top of other windows? It naw  
appears  
“under” other windows, so I only see the label if I keep the  
upper-left part  
of my screen free of other windows.
3. Is there a way to remove the borders? I don’t need the title bar.
4. I use this as a Mac OS X service, dufined with ThisService, a great  
little  
program. When I run it as a service, two windows appear. One is  
titled “tk”  
and the other is the same as what I see when I run the program from  
the  
command line. Can I get rid of the “tk” window?
5. Of course, is there a better way to do this?

– Pete

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<div class="post-metadata">

**Author:** ![siemsen](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/77aa72/32.png) [@siemsen](https://www.ruby-forum.com/u/siemsen)\
**Post date:** [August 18, 2007, 3:50am UTC](https://www.ruby-forum.com/t/basic-rubytk-questions/112339/2 "2007-08-18T03:50:23Z")

</div>

You are not very clear of what exaclty you intend to do, place what,  
where?, but I think Morton’s example can help you alot. Anyway if your  
target is only MacOS X try RubyCocoa  
([http://blog.8thlight.com/articles/2007/08/13/rubycocoa-tutorial](http://blog.8thlight.com/articles/2007/08/13/rubycocoa-tutorial)). I  
think you can use the XCode interface builder in that case.  
Regards.

---

<div class="post-metadata">

**Author:** ![siemsen](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/77aa72/32.png) [@siemsen](https://www.ruby-forum.com/u/siemsen)\
**Post date:** [August 18, 2007, 8:42pm UTC](https://www.ruby-forum.com/t/basic-rubytk-questions/112339/3 "2007-08-18T20:42:50Z")

</div>

On Aug 17, 2007, at 11:45 AM, Pete Siemsen wrote:

> I have a Mac OS X system. I wrote a Ruby program that uses RubyTk to  
> display a TkLabel. It works, but I’d like a bit more control over how  
> it looks. Here’s the code minus the non-Tk stuff that isn’t relevant  
> to my questions:

> 1. Of course, is there a better way to do this?

Now that _has_ has set me straight on how to use the osax library, I  
can suggest another idea:

`
#! /usr/bin/env ruby
require "osax"
SEC = 3 # display duration
std_adds = OSAX::osax(nil, “System Events”)
std_adds.display_alert(“This is a test”,
:message => “This is only a test”,
:giving_up_after => SEC,
:as => :warning)
`

Using OSA scripting additions has two virtues:

1. Much simpler to use than Ruby/Tk (once you know what library to  
require :).
2. As far as I can tell, the alert will always pop-up on top of any  
other window that might be present on the screen.

If all you want to do is pop-up an short message every now and then,  
this may work for you.

Regards, Morton

---

<div class="post-metadata">

**Author:** ![siemsen](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/77aa72/32.png) [@siemsen](https://www.ruby-forum.com/u/siemsen)\
**Post date:** [August 18, 2007, 2:55am UTC](https://www.ruby-forum.com/t/basic-rubytk-questions/112339/4 "2007-08-18T02:55:05Z")

</div>

On Aug 17, 2007, at 11:45 AM, Pete Siemsen wrote:

> foreground ‘yellow’  
> background ‘black’
> 
> # place(‘x’ =\> 400, ‘y’ = 400)
> 
> pack(‘padx’ =\> 15, ‘pady’ =\> 15)  
> end
> 
> def timer\_loop3  
> exit  
> end  
> TkAfter.new(3000, # milliseconds  
> -1, # ?

The -1 requests an indefinite number of timeout events. Since you are  
going to exit on the first timeout, I suggest using 1 here, but it  
doesn’t really matter.

> near the upper left-hand corner. I tried “place” (commented  
> out) with no  
> luck.

The ‘place’ method affects the geometry of a widget within its  
container. It does not affect the placement of the window containing  
the widget on the screen.

> 1. How can I make the label appear on top of other windows? It now  
> appears  
> “under” other windows, so I only see the label if I keep the  
> upper-left part  
> of my screen free of other windows.

The following ought to fix it, but it doesn’t.

```
root.focusmodel(:active)
root.focus(true)

```

This appears to be a problem with Tk. I don’t know a work-around.

> 1. Is there a way to remove the borders? I don’t need the title bar.

The borders, yes. The title bar I don’t know how to remove.

> 1. I use this as a Mac OS X service, defined with ThisService, a  
> great little  
> program. When I run it as a service, two windows appear. One  
> is titled “tk”  
> and the other is the same as what I see when I run the program  
> from the  
> command line. Can I get rid of the “tk” window?

If you watch carefully, sometimes you will see this window appear  
momentarily even when you run from the command line. I don’t know why  
it persists when you run your script as a service.

> 1. Of course, is there a better way to do this?

There’s always a better way to do something with Ruby 🙂 The  
following is the best I can do with Ruby/Tk. I don’t know if you will  
think it’s good enough, but it solves some of your problems.

`
#! /usr/bin/ruby -w
require 'tk'
SEC = 3 # display duration in seconds
TkLabel.new do
text ‘Hello, World!’
font “HelveticaBold 36”
foreground ‘yellow’
background ‘black’
pack(:fill => :both, :expand => true)
end
root = Tk.root
root.title(’’) # suppress title (title bar remains)
Set initial window geometry; i.e., size and placement
win_y, win_w, win_h = 50, 300, 80
win_x = (root.winfo_screenwidth - win_w) / 2 # center on screen
root.geometry("#{win_w}x#{win_h}+#{win_x}+#{win_y}")
Suppress resizing window
root.resizable(false, false)
One-shot timer
TkTimer.new(SEC * 1000, 1) { root.destroy }.start
Tk.mainloop
`

This may be a situation where Ruby/Tk just won’t cut it. The better  
way you are looking for may require using a GUI library other than  
Ruby/Tk.

Regards, Morton