Screen

Screen API requires node-webkit >= v0.10.2

Screen is an instance of EventEmitter object, and you're able to use Screen.on(...) to respond to native screen's events.

Screen is a singleton object, need to be initiated once by calling gui.Screen.Init()

Reference

Screen.Init()

Init the Screen singleton object, you only need to call this once

Screen.screens

return the array of screen

screen has following structure:

screen {
  id : int,   // unique id for a screen
  bounds : {  // physical screen resolution, can be negative, not necessarily start from 0,depending on screen arrangement
    x : int,
    y : int,
    width : int,
    height : int
  },
  work_area : { // useable area within the screen bound (due to native OS taskbar)
    x : int,
    y : int,
    width : int,
    height : int
  },
  scaleFactor : float,
  isBuiltIn : bool
}

Events

Following events can be listened by using Screen.on() function, for more information on how to receive events, you can visit EventEmitter.

displayBoundsChanged

emitted when the screen resolution, arrangement is changed

displayAdded

emitted when a new screen added

displayRemoved

emitted when existing screen removed

Synopsis

function ScreenToString(screen) {
  var string = "";
  string += "screen " + screen.id + " ";
  var rect = screen.bounds;
  string += "bound{" + rect.x + ", " + rect.y + ", " + rect.width + ", " + rect.height + "} ";
  rect = screen.work_area;
  string += "work_area{" + rect.x + ", " + rect.y + ", " + rect.width + ", " + rect.height + "} ";
  string += " scaleFactor: " + screen.scaleFactor;
  string += " isBuiltIn: " + screen.isBuiltIn;
  string += "<br>";
  return string;
}

//init must be called once during startup, before any function to gui.Screen can be called
gui.Screen.Init();
var string = "";
var screens = gui.Screen.screens;
// store all the screen information into string
for(var i=0; i<screens.length; i++) {
  string += ScreenToString(screens[i]);
}

var screenCB = {
  onDisplayBoundsChanged : function(screen) {
    var out = "OnDisplayBoundsChanged " + ScreenToString(screen);
  },

  onDisplayAdded : function(screen) {
    var out = "OnDisplayAdded " + ScreenToString(screen);
  },

  onDisplayRemoved : function(screen) {
    var out = "OnDisplayRemoved " + ScreenToString(screen);
  }
};

// listen to screen events
gui.Screen.on('displayBoundsChanged', screenCB.onDisplayBoundsChanged);
gui.Screen.on('displayAdded', screenCB.onDisplayAdded);
gui.Screen.on('displayRemoved', screenCB.onDisplayRemoved);