iPad Web App: Detect Virtual Keyboard Using JavaSc

Question

I'm writing a web app for the iPad (not a regular App Store app - it's written using HTML, CSS and JavaScript). Since the keyboard fills up a huge part of the screen, it would make sense to change the app's layout to fit the remaining space when the keyboard is shown. However, I have found no way to detect when or whether the keyboard is shown.

My first idea was to assume that the keyboard is visible when a text field has focus. However, when an external keyboard is attached to an iPad, the virtual keyboard does not show up when a text field receives focus.

In my experiments, the keyboard also did not affect the height or scrollheight of any of the DOM elements, and I have found no proprietary events or properties which indicate whether the keyboard is visible.

Answer 1

Perhaps it's easier to have a checkbox in your app's settings where the user can toggle 'external keyboard attached?'.

In small print, explain to the user that external keyboards are currently not detectable in today's browsers.

Answer 2

Try this one:

var lastfoucsin;

$('.txtclassname').click(function(e)
{
  lastfoucsin=$(this);

//the virtual keyboard appears automatically

//Do your stuff;

});


//to check ipad virtual keyboard appearance. 
//First check last focus class and close the virtual keyboard.In second click it closes the wrapper & lable

$(".wrapperclass").click(function(e)
{

if(lastfoucsin.hasClass('txtclassname'))
{

lastfoucsin=$(this);//to avoid error

return;

}

//Do your stuff 
$(this).css('display','none');
});`enter code here`

Answer 3

I found a solution which works, although it is a bit ugly. It also won't work in every situation, but it works for me. Since I'm adapting the size of the user interface to the iPad's window size, the user is normally unable to scroll. In other words, if I set the window's scrollTop, it will remain at 0.

If, on the other hand, the keyboard is shown, scrolling suddenly works. So I can set scrollTop, immediately test its value, and then reset it. Here's how that might look in code, using jQuery:

$(document).ready(function(){
    $('input').bind('focus',function() {
        $(window).scrollTop(10);
        var keyboard_shown = $(window).scrollTop() > 0;
        $(window).scrollTop(0);

        $('#test').append(keyboard_shown?'keyboard ':'nokeyboard ');
    });
});

Normally, you would expect this to not be visible to the user. Unfortunately, at least when running in the Simulator, the iPad visibly (though quickly) scrolls up and down again. Still, it works, at least in some specific situations.

I've tested this on an iPad, and it seems to work fine.

Answer 4

Instead of detecting the keyboard, try to detect the size of the window

If the height of the window was reduced, and the width is still the same, it means that the keyboard is on. Else the keyboard is off, you can also add to that, test if any input field is on focus or not.

Try this code for example.

var last_h = $(window).height(); //  store the intial height.
var last_w = $(window).width(); //  store the intial width.
var keyboard_is_on = false;
$(window).resize(function () {
    if ($("input").is(":focus")) {
        keyboard_is_on =
               ((last_w == $(window).width()) && (last_h > $(window).height()));
    }   
});