How to run fullscreen in an Android Chrome app

This works on both the Desktop and Android devices.

To use it, add a button to your app with the following code:

// JavaScript
function btnChrome_onclick() {
  document.documentElement.webkitRequestFullScreen();
}

' Basic
Function btnChrome_onclick()
  document.documentElement.webkitRequestFullScreen()
End Function

After going to full screen, a message is displayed telling how to go back: swipe down on an Android device or hit escape on the desktop.

If you want to execute some code after the resize (perhaps to move controls to take advantage of the larger screen, do the following:

// JavaScript
function window_onresize() {
  console.log('resize')
  // … do any housekeeping
}

' Basic
Function window_onresize()
  Print "resize"
  '… do any housekeeping
End Function

If you want hide the button if you are not using Chrome, add this code to your global code:

// JavaScript
if (!window.chrome) btnChrome.hide();

' Basic
If Not window.chrome Then btnChrome.hide()

A few gotchas:

This won't work with iOS.
It seems to have to be done from a button: just putting it in Global Code does not work.

Built-in Fullscreen Mode in Chrome for Android

Alternatively, any AppStudio web app can run in fullscreen mode on Chrome for Android by opening the app in the browser, then:

Tapping the Menu button (three vertical dots) in the upper right-hand corner of the screen (or tap the hardware menu button on those devices having one)
Selecting Add to homescreen from the menu
Tapping the Add button in the pop up dialog
Then, from the home screen, tap the app icon to open in fullscreen mode.

This is a newer Chrome feature than the first method described above and is typically the preferable option.

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