Class: Iup::Button

Inherits:
Widget show all
Includes:
ButtonCallback, ImageAttributes
Defined in:
lib/wrapped/button.rb

Overview

A button can display some text, an image, or both.

When clicked, a specified action function is called.

The action should return Iup::DEFAULT, or, if the button should exit the application, Iup::CLOSE.

# Example 1: A button with some text and an action
Button.new 'click me', ->{
  puts 'clicked'
  DEFAULT
}

# Example 2: a button with an image stored in +img+ and 
# action specified by a separate method; some padding around 
# the image within the button.
def click_fn
  puts 'clicked'
  DEFAULT
end

Button.new '', ->{ click_fn } do
  image img
  padding '50x20'
end

# Example 3: a button with text and image, image placed above
# text.  The text contains an & before the "x", so the action
# can be triggered using ALT+x, and closes the application.
Button.new 'e&xit', ->{ puts 'exit'; CLOSE } do
  image img
  imageposition 'top'
end

Attributes

alignment

Sets the horizontal and vertical alignment. The value is a string “horizontal:vertical”, with options ALEFT, ACENTER, ARIGHT or none.

canfocus

Enables the control to gain focus. Values ‘yes’ / ‘no’.

expand

Allows button to fill available space in indicated direction. Values ‘no’ / ‘horizontal’ / ‘vertical’ / ‘yes’.

flat

If set, hides the button’s border until mouse enters the button area. Values ‘yes’ / ‘no’.

impressborder

If set, shows button borders even if impress defined. Values ‘yes’ / ‘no’.

imageposition

Position of image relative to text. Values ‘left’ / ‘right’ / ‘top’ / ‘bottom’/

padding

Margin in x and y directions, value as “mxn”.

position

read-only returns position in pixels within client window as “x,y”.

rastersize

Size of the button, in pixels, value as “widthxheight”.

screenposition

read-only returns position in pixels on screen as “x,y”.

spacing

Space between image and text, value as a number.

tip

Tooltip string.

title

Label text displayed on the button.

Instance Attribute Summary

Attributes inherited from Widget

#handle

Instance Method Summary collapse

Methods included from ButtonCallback

#button_cb

Methods included from ImageAttributes

#image, #iminactive, #impress

Methods included from AttributeReference

#attribute_reference

Methods inherited from Widget

#assign_handle, #enterwindow_cb, #getfocus_cb, #help_cb, #k_any, #killfocus_cb, #leavewindow_cb, #map_cb, #open_controls, #unmap_cb

Methods included from AttributeBuilders

#define_attribute, #define_id_attribute, #define_id_readonly, #define_id_writeonly, #define_property_attribute, #define_property_writeonly, #define_readonly, #define_writeonly

Methods included from CallbackSetter

#define_callback

Constructor Details

#initialize(title = '', callback = nil, &block) ⇒ Button

Creates an instance of a button.

title

the text to display on the button.

callback

procedure to call when button is left-clicked.

block

optional block to set up the button’s attributes.



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# File 'lib/wrapped/button.rb', line 66

def initialize title='', callback = nil, &block
  @handle = IupLib.IupButton title, nil

  action callback unless callback.nil?

  # run any provided block on instance, to set up further attributes
  self.instance_eval &block if block_given?
end

Instance Method Details

#action(callback) ⇒ Object

Action generated when the button 1 (usually left) is selected.



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# File 'lib/wrapped/button.rb', line 95

def action callback
  unless callback.arity.zero?
    raise ArgumentError, 'action must take 0 arguments'
  end
  cb = Proc.new do |ih|
    callback.call
  end
  define_callback cb, 'ACTION', :plain
end