[wxruby-users] set the background to a bitmap

[Alex Fenton]

John Griffiths wrote:
> any ideas whether you can set the background of a dialog to use an
> image?

Use evt_erase_background, which is meant for this:
http://wxruby.rubyforge.org/doc/eraseevent.html

The example below just fills with colour, but you could replace the call 
to gradient_fill_linear with one to DC#draw_bitmap or whatever other 
drawing/painting code yoou wanted. Please, just don't do anything as 
eyesore as this ...

alex
__
require 'wx'

class BackgroundDialog < Wx::Dialog
  def initialize(parent)
    super(parent, :title => "dialog with background")
    Wx::TextCtrl.new(self, :value => 'foo', :pos => [ 50, 50 ])
    evt_erase_background :on_erase_background
  end

  def on_erase_background(evt)
    # Use the event's DC object to draw whatever background you want
    evt.dc.gradient_fill_linear( client_rect,
                                 Wx::RED, Wx::BLACK, Wx::NORTH )
  end
end

Wx::App.run do
  frame = Wx::Frame.new(nil, :title => 'frame')
  frame.show
  BackgroundDialog.new(frame).show
end