electron/docs/api/screen.md
2015-10-04 20:14:52 -06:00

2.8 KiB

screen

The screen module retrieves information about screen size, displays, cursor position, etc. You should not use this module until the ready event of the app module is emitted.

screen is an EventEmitter.

Note: In the renderer / DevTools, window.screen is a reserved DOM property, so writing var screen = require('screen') will not work. In our examples below, we use electronScreen as the variable name instead.

An example of creating a window that fills the whole screen:

var app = require('app');
var BrowserWindow = require('browser-window');

var mainWindow;

app.on('ready', function() {
  var electronScreen = require('screen');
  var size = electronScreen.getPrimaryDisplay().workAreaSize;
  mainWindow = new BrowserWindow({ width: size.width, height: size.height });
});

Another example of creating a window in the external display:

var app = require('app');
var BrowserWindow = require('browser-window');

var mainWindow;

app.on('ready', function() {
  var electronScreen = require('screen');
  var displays = electronScreen.getAllDisplays();
  var externalDisplay = null;
  for (var i =0; i< displays.length; i++) {
    if (displays[i].bounds.x !==0 || displays[i].bounds.y !== 0) {
      externalDisplay = displays[i];
      break;
    }
  }

  if (externalDisplay) {
    mainWindow = new BrowserWindow({
      x: externalDisplay.bounds.x + 50,
      y: externalDisplay.bounds.y + 50,
       width: 900,
       height:600
    });
  }
});

Events

The screen module emits the following events:

Event: 'display-added'

Returns:

  • event Event
  • newDisplay Object

Emitted when newDisplay has been added.

Event: 'display-removed'

Returns:

  • event Event
  • oldDisplay Object

Emitted when oldDisplay has been removed.

Event: 'display-metrics-changed'

Returns:

  • event Event
  • display Object
  • changedMetrics Array

Emitted when one or more metrics change in a display. The changedMetrics is an array of strings that describe the changes. Possible changes are bounds, workArea, scaleFactor and rotation.

Methods

The screen module has the following methods:

screen.getCursorScreenPoint()

Returns the current absolute position of the mouse pointer.

screen.getPrimaryDisplay()

Returns the primary display.

screen.getAllDisplays()

Returns an array of displays that are currently available.

screen.getDisplayNearestPoint(point)

  • point Object
    • x Integer
    • y Integer

Returns the display nearest the specified point.

screen.getDisplayMatching(rect)

  • rect Object
    • x Integer
    • y Integer
    • width Integer
    • height Integer

Returns the display that most closely intersects the provided bounds.