# A silly little calculator implemented in Jacl using
# Java components for the UI.

package require java

set f [java::new java.awt.Frame "BSH Calculator (jacl/tcl)"]
bsf addEventListener $f "window" "windowClosing" "exit"
set p [java::new java.awt.Panel]

set f1 [java::new java.awt.TextField]
$f1 setColumns 20
bsf addEventListener $f1 "action" "" "doMath"
set f2 [java::new java.awt.TextField]
bsf addEventListener $f2 "text" "" "doMath"

set p [java::new java.awt.Panel]
$p setLayout [java::new java.awt.GridLayout 2 2]
$p add [java::new java.awt.Label "Enter Operand"]
$p add $f1
$p add [java::new java.awt.Label "Enter Operand"]
$p add $f2

$f add "North" $p

$f add "Center" [java::new java.awt.Label "Results:"]

set p [java::new java.awt.Panel]
$p setLayout [java::new java.awt.GridLayout 4 2]
$p add [java::new java.awt.Label "Sum"]
$p add [set sum [java::new java.awt.TextField]]
$sum setColumns 20
$p add [java::new java.awt.Label "Difference"]
$p add [set diff [java::new java.awt.TextField]]
$p add [java::new java.awt.Label "Product"]
$p add [set prod [java::new java.awt.TextField]]
$p add [java::new java.awt.Label "Quotient"]
$p add [set quo [java::new java.awt.TextField]]
$f add "South" $p

$f pack
$f show
$f toFront

proc getField {f} {
  set t [$f getText]
  if {$t == ""} {
    return 0
  } else {
    return [java::call java.lang.Integer parseInt $t]
  }
}

proc doMath {} {
  global f1 f2 sum diff prod quo
  set n1 [getField $f1]
  set n2 [getField $f2]
  $sum setText [expr $n1 + $n2]
  $diff setText [expr $n1 - $n2]
  $prod setText [expr $n1 * $n2]
  $quo setText [expr $n1 / $n2]
}