GUI scripting

News
1

The Gambas project has a nice jitted scripter which can be called from crystal for small GUIs, here just a textarea. Lets see if we can talk to this ‘alien’ objects and types in a more direct way.
Should we call this crybas ? Hope it is useful.


#Define GUI in an heredoc
gui =<<-'GUI'
use "gb.form"
DIM Line$ As String
DIM myForm AS Form
With myForm = New Form
   .Title = "Text Viewer" 
   .Arrangement = Arrange.Fill 
   .AutoResize = False
   .width = 600
   .height = 300
   .show
End with
DIM myText As New TextArea(myForm)
file.in.blocking = false
DO
  Line$ = Read -1024       'read up to 1024 Bytes from stdin
  myText.Insert(Line$)     'insert text into text area
  wait 0.01                'give time to Gambas events
LOOP
GUI
File.write("./gui.gbs",gui)
spawn do; begin  
    cmd = "gbs3 ./gui.gbs"
    Process.run(cmd, shell: true) do | p |
         p.input.puts("hello textarea")     
         p.input.puts("crystal+gambas = crybas")                
       end 
    end
end
sleep
1 Like
2

It would probably be more efficient to write some C bindings to it (if possible) rather than spawning a sub process. Given most higher level languages can do this I’m not sure what you’re trying to show here? Not really getting any benefit from using Crystal in this case.

3

The benefit could be:
-to re-use a VB like GUI designer for crystal projects
-or just script small GUIs when you do not need the GUI designer(just 2 or 3 GUI elements)
Crystals semantik and syntax is much more compact and modern. I dont want to re-envent the wheel. I need an object bridge between the crystal <-> gambas side. I can imagine to write a text based object bridge(key,value pairs) for GUI objects and GUI events based on sockets or pipes in some evenings.

4

Setting Properties of a Gambas GUI Object like: Textarea1.Text=“some text”
already works. This is done by doing live object introspection by the received object name e.g. a Textarea has 106 symbols for properties,methods and events

Received data <–
Textarea1.Text,2020-05-21 11:46:37 +02:00
Key,val: Textarea1.Text 2020-05-21 11:46:37 +02:00

Objname: Textarea1
Prop: Text
(TextArea 0x55e41302e6c8)
TextArea1:
.,H,W,X,Y,Id,Cut,Pos,Tag,Top,_new,Copy,Drag,Drop,Font,Grab,Hide,Left,Line,Move,Name,Next,Redo,Show,Text,Undo,Wrap,:Drag,:Drop,:Menu
,Clear,Lower,Mouse,Paste,Proxy,Raise,ToPos,Width,:Enter,:Leave,Action,Border,Column,Cursor,Delete,Design,Expand,Handle,Height,Ignor
e,Insert,Length,Parent,Resize,Select,ToLine,Window,:Change,:Cursor,_Family,_Parent,Enabled,Hovered,Refresh,ScreenX,ScreenY,Tooltip,
Visible,:MouseUp,_Similar,CursorAt,HasFocus,Previous,ReadOnly,Reparent,Selected,SetFocus,ToColumn,Tracking,Unselect,:DblClick,:Drag
Move,:GotFocus,:KeyPress,Alignment,PopupMenu,ScrollBar,SelectAll,Selection,:DragLeave,:LostFocus,:MouseDown,:MouseDrag,:MouseMove,_
IsControl,Background,Foreground,MoveScaled,NoTabFocus,:KeyRelease,:MouseWheel,_Properties,_DefaultSize,ResizeScaled,_DefaultEvent,E
nsureVisible,
Symbols found: 106

Events for Button pressed are working, I just send “Button nn Clicked” to crystal.

#connect to Gambas GUI via TCP
require "socket"
GUI_SERVER="localhost"
GUI_PORT=9090
class GuiClient
  def send (object,value)
    client = TCPSocket.new(GUI_SERVER,GUI_PORT)
    client << object + "," + value + "\n"
    response = client.gets
    client.close
    puts 
  end    
end
mygui = GuiClient.new
#send key,value pairs for GUI Objects based on GTK or QT 
mygui.send "Textarea1.Text","hello-textarea"
sleep 5.seconds
mygui.send "Textarea1.Text","hello-textarea-more-text"
loop do 
    mygui.send "Textarea1.Text",Time.local.to_s
    sleep 2.seconds
end
sleep


Event for Button clicks forwarded like this:
def receive
    spawn do  #receiving fiber,handle GUI events
        loop do    
            event = @client.not_nil!.gets
            case event 
            when "Button1 clicked"
              @sending=false
            when "Button2 clicked"
              @sending=true    
            end
          end
        end
    end
end
5

A Gambas TCP GUI Server Demo App is available.
Download: https://gambas.one/gambasfarm/?id=821&action=search
Connect with any Telnet client or with your Crystal App.
https://www.bitkistl.com/2020/05/gambas3-gui-server.html