Bootstrap 3 collapse can have multiple panels open after programmatically opening a panel

Question

I have a problem with bootstrap 3 collapse, after opening a panel programmatically it is possible to keep another panel open while reopening the first panel.

My HTML:

<button type="button" class="btn showpanel">Show panel 3</button>
<button type="button" class="btn hidepanel">Hide panel 3</button>
<button type="button" class="btn openpanel">Open panel 3</button>
<button type="button" class="btn closepanel">Close panel 3</button>
<hr/>
<div class="panel-group" id="accordion">
    <div class="panel panel-default">
        <div class="panel-heading">
            <h4 class="panel-title">
                <a class="accordion-toggle" data-toggle="collapse" data-parent="#accordion" href="#panel1">Panel 1</a>
            </h4>
        </div>
        <div id="panel1" class="panel-collapse collapse">
            <div class="panel-body">
                Contents panel 1
            </div>
        </div>
    </div>
    <div class="panel panel-default">
        <div class="panel-heading">
            <h4 class="panel-title">
                <a class="accordion-toggle" data-toggle="collapse" data-parent="#accordion" href="#panel2">Panel 2</a>
            </h4>
        </div>
        <div id="panel2" class="panel-collapse collapse">
            <div class="panel-body">
                Contents panel 2
            </div>
        </div>
    </div>
    <div class="panel panel-default">
        <div class="panel-heading">
            <h4 class="panel-title">
                <a class="accordion-toggle" data-toggle="collapse" data-parent="#accordion" href="#panel3">Panel 3</a>
            </h4>
        </div>
        <div id="panel3" class="panel-collapse collapse">
            <div class="panel-body">
                Contents panel 3
            </div>
        </div>
    </div>
</div>

And some JavaScript:

$(".hidepanel").on("click", function() {
    $("#panel3").parent().hide();
});
$(".showpanel").on("click", function() {
    $("#panel3").parent().show();
});
$(".openpanel").on("click", function() {
    $("#panel3").collapse('show');
});
$(".closepanel").on("click", function() {
    $("#panel3").collapse('hide');
});

My jsfiddle that demonstrates this issue

To reproduce:

1. Click the button 'Open panel 3'.
2. Click 'Panel 2' to open it. So far no problems.
3. Click 'Panel 3' to open it again. Panel 2 remains open!

So opening a panel programmatically seems to mess up bootstraps internal registration about panel states? I don't see anything visibly wrong with the 'state change' of the third panel (it's class changes from 'collapse' to 'in' and back as you would expect).

Answer 1

You can create a handler for the collapse show event which occurs just before any panels are displayed.

Add this to ensure any other open panels are closed before the selected one is shown:

$('#accordion').on('show.bs.collapse', function () {
    $('#accordion .in').collapse('hide');
});

Bootply demo

You can read more about the collapse events here: http://getbootstrap.com/javascript/#collapse