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#!/usr/bin/gjs
const GObject = imports.gi.GObject;
const Gtk = imports.gi.Gtk;
const Lang = imports.lang;
const ButtonBoxExample = new Lang.Class ({
Name: 'ButtonBox Example',
// Create the application itthis
_init: function () {
this.application = new Gtk.Application({ application_id: 'org.example.jsbuttonbox' });
// Connect 'activate' and 'startup' signals to the callback functions
this.application.connect('activate', Lang.bind(this, this._onActivate));
this.application.connect('startup', Lang.bind(this, this._onStartup));
},
// Callback function for 'activate' signal presents windows when active
_onActivate: function() {
this.window.present();
},
// Callback function for 'startup' signal builds the UI
_onStartup: function() {
this._buildUI ();
},
// Build the application's UI
_buildUI: function() {
// Create the application window
this.window = new Gtk.ApplicationWindow ({ application: this.application,
window_position: Gtk.WindowPosition.CENTER,
title: "Calculator",
default_width: 350,
default_height: 200,
border_width: 10 });
this.entry = new Gtk.Entry();
this.entry.set_text('0');
// text aligned on the right
this.entry.set_alignment(1);
// the text in the entry cannot be modified by writing in it
this.entry.set_can_focus(false);
// a grid
this.grid = new Gtk.Grid();
this.grid.set_row_spacing(5);
// to attach the entry
this.grid.attach(this.entry, 0, 0, 1, 1);
// the labels for the buttons
this.buttons = [ 7, 8, 9, '/', 4, 5, 6, '*', 1, 2, 3, '-', 'C', 0, '=', '+' ];
// each row is a ButtonBox, attached to the grid
for (i = 0; i < 4; i++) {
this.hbox = Gtk.ButtonBox.new(Gtk.Orientation.HORIZONTAL);
this.hbox.set_spacing(5);
this.grid.attach(this.hbox, 0, i + 1, 1, 1);
// each ButtonBox has 4 buttons, connected to the callback function
for (j= 0; j < 4; j++) {
this.button = new Gtk.Button();
this.buttonLabel = (this.buttons[i * 4 + j].toString());
this.button.set_label(this.buttonLabel);
this.button.set_can_focus(false);
this.button.connect("clicked", Lang.bind(this, this._buttonClicked, this.button));
this.hbox.add(this.button);
}
}
// some variables for the calculations
this.firstNumber = 0;
this.secondNumber = 0;
this.counter = 0;
this.operation = "";
// add the grid to the window
this.window.add(this.grid);
this.window.show_all();
},
// callback function for all the buttons
_buttonClicked: function(button) {
this.button = button;
// for the operations
if (this.button.get_label() == '+') {
this.counter += 1
if (this.counter > 1)
this._doOperation();
this.entry.set_text('0');
this.operation = "plus";
}
else if (this.button.get_label() == '-') {
this.counter += 1;
if (this.counter > 1)
this._doOperation();
this.entry.set_text('0');
this.operation = "minus";
}
else if (this.button.get_label() == '*') {
this.counter += 1;
if (this.counter > 1)
this._doOperation();
this.entry.set_text('0');
this.operation = "multiplication";
}
else if (this.button.get_label() == '/') {
this.counter += 1
if (this.counter > 1)
this._doOperation();
this.entry.set_text('0');
this.operation = "division";
}
// for =
else if (this.button.get_label() == '=') {
this._doOperation();
this.entry.set_text(this.firstNumber.toString());
this.counter = 1;
}
// for Cancel
else if (this.button.get_label() == 'C') {
this.firstNumber = 0;
this.secondNumber = 0;
this.counter = 0;
this.entry.set_text('0');
this.operation = "";
}
// for a digit button
else {
this.newDigit = parseInt(this.button.get_label());
if (this.entry.get_text() == "error")
this.number = 0;
else
this.number = parseInt(this.entry.get_text());
this.number = this.number * 10 + this.newDigit;
if (this.counter == 0)
this.firstNumber = this.number;
else
this.secondNumber = this.number;
this.entry.set_text(this.number.toString());
}
},
_doOperation: function() {
if (this.operation == "plus") {
this.firstNumber += this.secondNumber;
} else if (this.operation == "minus") {
this.firstNumber -= this.secondNumber;
} else if (this.operation == "multiplication") {
this.firstNumber *= this.secondNumber;
} else if (this.operation == "division") {
if (this.secondNumber != 0) {
this.firstNumber /= this.secondNumber;
} else {
this.firstNumber = 0;
this.secondNumber = 0;
this.counter = 0;
this.entry.set_text("error");
this.operation = "";
return
}
} else {
this.firstNumber = 0;
this.secondNumber = 0;
this.counter = 0;
this.entry.set_text("error");
}
}
});
// Run the application
let app = new ButtonBoxExample();
app.application.run (ARGV);
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