GUI enabling/disabling of controls: Difference between revisions

==={{libheader|gintro}}===

<lang Nim>import strutils

import gintro/[glib, gobject, gtk, gio]

type Context = ref object

value: int

entry: Entry

btnIncr: Button

btnDecr: Button

#---------------------------------------------------------------------------------------------------

proc checkButtons(ctx: Context) =

ctx.btnIncr.setSensitive(ctx.value < 10)

ctx.btnDecr.setSensitive(ctx.value > 0)

ctx.entry.setSensitive(ctx.value == 0)

#---------------------------------------------------------------------------------------------------

proc onQuit(button: Button; window: ApplicationWindow) =

window.destroy()

#---------------------------------------------------------------------------------------------------

proc onIncr(button: Button; ctx: Context) =

inc ctx.value

ctx.entry.setText($ctx.value)

ctx.checkButtons()

#---------------------------------------------------------------------------------------------------

proc onDecr(button: Button; ctx: Context) =

dec ctx.value

ctx.entry.setText($ctx.value)

ctx.checkButtons()

#---------------------------------------------------------------------------------------------------

proc onEntryChange(entry: Entry; ctx: Context) =

try:

ctx.value = entry.text().parseInt()

except ValueError:

entry.setText($ctx.value)

#---------------------------------------------------------------------------------------------------

proc activate(app: Application) =

## Activate the application.

let window = app.newApplicationWindow()

window.setTitle("GUI controls")

let content = newBox(Orientation.vertical, 10)

content.setHomogeneous(true)

let hbox1 = newBox(Orientation.horizontal, 10)

hbox1.setHomogeneous(true)

let hbox2 = newBox(Orientation.horizontal, 1)

hbox2.setHomogeneous(false)

let label = newLabel("Value:")

let entry = newEntry()

entry.setText("0")

let btnQuit = newButton("Quit")

let btnIncr = newButton("Increment")

let btnDecr = newButton("Decrement")

hbox2.add(label)

hbox2.add(entry)

hbox1.add(btnIncr)

hbox1.add(btnDecr)

content.packStart(hbox2, true, true, 0)

content.packStart(hbox1, true, true, 0)

content.packStart(btnQuit, true, true, 0)

window.setBorderWidth(5)

window.add(content)

let context = Context(value: 0, entry: entry, btnIncr: btnIncr, btnDecr: btnDecr)

discard btnQuit.connect("clicked", onQuit, window)

discard btnIncr.connect("clicked", onIncr, context)

discard btnDecr.connect("clicked", onDecr, context)

discard entry.connect("changed", onEntryChange, context)

context.checkButtons()

window.showAll()

#———————————————————————————————————————————————————————————————————————————————————————————————————

let app = newApplication(Application, "Rosetta.GuiControls")

discard app.connect("activate", activate)

discard app.run()</lang>