将两个点击事件添加到同一按钮仅一次

Question

Basically I'm trying to make a button be able to handle editing of an element. I want it so that when I click on the Edit button, it changes the text to Save Changes and adds a class which will then bind the button to another click event so that when they click Save Changes , it'll alert Saved and change the text back to Edit . It does this perfectly once. If you continue to try to do it, it simply won't add the class or change the text anymore.

Here is a demo on jsfiddle

The code:

$(function() {
$button = $('button[name="edit"]');
$button.on('click', $button, function() {
    var $that = $(this);
    $that.text('Save Changes');
    $that.addClass('js-editing');
    if ($that.hasClass('js-editing')) {
        $that.off('click').on('click', $that, function() {
            alert('Saved!');
            $that.text('Edit');
            $that.removeClass('js-editing');
        });
    }
});

});​

Answer 1

Try this http://jsfiddle.net/bpD8B/4/

$(function() {
    $button = $('button[name="edit"]');
    $button.on('click', $button, function() {
        var $that = $(this);
        if($that.text()=='Edit'){
          $that.text('Save Changes');
          $that.addClass('js-editing');
        }
        else{
                alert('Saved!');
                $that.text('Edit');
                $that.removeClass('js-editing');
        }
    });
});

Answer 2

You never add back the original handler after calling off(), which removes it.

That being said, it might be easier to have two buttons, with appropriate click handlers, and then use hide() and show() to alternate which one is available. To the end user it should look and act exactly the same, and to you it will be a lot less of a headache to code.

Example: http://jsfiddle.net/VgsLA/

I think in the end, this code is more robust and manageable.

Answer 3

This is just a logic problem. And with $that.off('click').on('click', $that, function() { you are delegating to itself, which is not how you should do it.

Here is a solution using your code:

$(function() {

    $button = $('button[name="edit"]');
    $button.on('click', $button, function() {
        var $that = $(this);
        if ($that.hasClass('js-editing')) {
            alert('Saved!');
            $that.text('Edit');
            $that.removeClass('js-editing');        
        } else {      
            $that.text('Save Changes'); 
            $that.addClass('js-editing');
        }
    });

});​

Demo