[Kde-bindings] QT TextEdit refresh

[Richard Dale]

On Tuesday 24 July 2007, Carl Bourne wrote:
> require 'Qt'
> require 'dialog.rb'
> app = Qt::Application.new(ARGV)
> dialog = Dialog.new
> dialog.exec
>  
> ------
> dialog.rb
> -------
>  
> class MyWidget < Qt::Widget
>   slots 'go()'
>   def initialize(parent = nil)
>     super(parent)
>     setFixedSize(500, 500)
>     @textedit = Qt::TextEdit.new(self)
>     @textedit.setGeometry(5, 50, 480, 300)
>  
>     quit = Qt::PushButton.new(('Generate'), self)
>     quit.setGeometry(5, 5, 100, 30)
>     quit.setFont(Qt::Font.new('Arial', 12, Qt::Font::Bold))
>     connect(quit, SIGNAL(:clicked)) {@textedit.clear();  go() }
>   end
>    
>   def go
>       #   @textedit.clear()
>       @textedit.setText("Generating files:-")
>       count = 0
>       50.times do
>         count+=1
>         sleep 0.1
>         @textedit.append("Generating file: "+count.to_s)    
>         puts "hello"
>       end
>       @textedit.append("Done")
>   end
> end
> app = Qt::Application.new(ARGV)
> widget = MyWidget.new()
> widget.show()
> app.exec()
The Qt::TextEdit won't get repainted until you return to the event loop. So if 
you do everything inside to go() method you won't return to the event loop 
until you've done the 50 iterations.

You need to do the 'Generating files' processing in another method, that is 
called once before control returns to the event loop like this for instance:

class MyWidget < Qt::Widget
  slots :go, :generate
  def initialize(parent = nil)
    super(parent)
    setFixedSize(500, 500)
    @textedit = Qt::TextEdit.new(self)
    @textedit.setGeometry(5, 50, 480, 300)

    quit = Qt::PushButton.new(('Generate'), self)
    quit.setGeometry(5, 5, 100, 30)
    quit.font = Qt::Font.new('Arial', 12, Qt::Font::Bold)
    connect(quit, SIGNAL(:clicked)) {@textedit.clear(); go() }
  end
  
  def go
      #   @textedit.clear()
      @textedit.text = "Generating files:-"
      @count = 0
      generate
  end

  def generate
     @count += 1
     @textedit.append("Generating file: "+ at count.to_s)   
     puts "hello"
     if @count == 50
       @textedit.append("Done")
     else
       @timer = Qt::Timer.singleShot(100, self, SLOT(:generate))
     end
  end
end


PS: The two pieces of your code didn't seem to quite match as there was no 
Dialog class in dialog.rb..

-- Richard