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JavaScript

Why does boolean switch not work (jQuery)?

I am setting a global boolean ('overlayVisible') to true when '.overlay' is clicked.

var overlayVisible = false;

// 1 Capture click (of last list item)
if (overlayVisible === false) {
    $('li:last-child').click(function () {

        // show the overlay
        $('.overlay').show('fast');
        overlayVisible = !overlayVisible;

    });
}

However, when checking to see if 'overlayVisible' is true, the code never runs. (I never see the 'bang!' written out to the console)

// 3 When (last list item) clicked again
if (overlayVisible) {

    console.log('bang!');

    // hide overlay
    $('li:last-child').click(function () {

        console.log('hidden!');

        // hide the overlay
        $('.overlay').hide();
        overlayVisible = false;

    });
}

Why is this happening? Thank you.

1 Answer

Matt F.
Matt F.
9,518 Points

Hi James,

I cannot be sure without the remainder of your code - but my suspicion is that your second block of code is executing on initialization - when overlayVisible is equal to false - therefore never running what is in your if block.

Try this instead:

    // hide overlay
    $('li:last-child').click(function () {


         // 3 When (last list item) clicked again
         if (overlayVisible) {

              console.log('bang!');

              console.log('hidden!');

               // hide the overlay
               $('.overlay').hide();
               overlayVisible = false;
          }
    });

Thank you! It didn't work exactly as you put it, but I applied your method to the entire script and it worked!!

var overlayVisible = false;

$('li:last-child').click(function () {

    if (overlayVisible === false) {
        // show the overlay
        $('.overlay').show('fast');

    } else {
        // hide the overlay
        $('.overlay').hide();
    }
    overlayVisible = !overlayVisible;
});