在JavaScript类中添加回调功能

Question

I'm trying to create a javascript class which opens a jQuery dialog and allows the user to select an option then returns the selected value in a callback.

...similar to how the jQuery Alert Dialogs do it.

jPrompt(message, [value, title, callback])

jPrompt('Type something:', 'Prefilled value', 'Prompt Dialog', function(r) {
    if( r ) alert('You entered ' + r);
});

Here is a DEMO of what i have so far. But if you notice, the value gets set imidiately, and i want it to wait until the user clicks OK. If the user clicks Cancel, then it should return null or empty string.

Here's my Javascript Class :

var namespace = {};
(namespace.myChooser = function () {
    var _dialog = null;
    /** 
    * Function : onButtonCancel
    */
    function onButtonCancel() {
        _dialog.dialog("close");
        return null;
    }
    /** 
    * Function : onButtonOK
    */
    function onButtonOK() {
        _dialog.dialog("close");
    }
    /** 
    * Function : Initialize
    */
    function Init() {
        var dialog_options = {
            modal: false,
            disabled: false,
            resizable: false,
            autoOpen: false,
            //height: 460,
            maxHeight: 300,
            zIndex: 500,
            stack: true,
            title: 'My Chooser',
            buttons: { "OK": onButtonOK, "Cancel": onButtonCancel }
        };
        _dialog = $("#myDialog");
        // create dialog.
        _dialog.dialog(dialog_options);
        _dialog.dialog("open");
    }

    return {
        Choose: function Choose() {
            Init();
            var myChoice = $("#myOptions").val();
            return myChoice;
        }
    }
}());

And i want to be able to do something like this:

namespace.myChooser.Choose(function (myChoice) {
       $("span#myChoice").text(myChoice);
    });

SOLUTION: This is what finally did it:

$(document).ready(function () {

    $('#myButton').click(function () {
        namespace.myChooser.Choose(function (x) {
            console.log(x);
        });
    });

});

var namespace = {};
(namespace.myChooser = function (callback) {
    function _show(callback) {
            var dialog_options = {
                modal: false,
                disabled: false,
                resizable: false,
                autoOpen: false,
                //height: 460,
                maxHeight: 300,
                zIndex: 500,
                stack: true,
                title: 'My Chooser',
                buttons: { 
                    "OK": function () {
                        if (callback) callback("OK");
                    },
                    "Cancel": function () {
                        if (callback) callback("Cancel");
                    }
                }
            };
            _dialog = $("#myDialog");
            // create dialog.
            _dialog.dialog(dialog_options);
            _dialog.dialog("open");
    }

    return {
        Choose: function (callback) {
            _show(function (result){
                if (callback) callback(result);
            });
        }
    }
}());

Answer 1

Choose: function Choose(cb) {
    Init();
    var myChoice = $("#myOptions").val();
    return cb(myChoice);
}

Should do what you want

Answer 2

Add another variable where you have var _dialog , call it something like var _callback . Then in your Choose function, add a parameter to get the callback function and store it, something like:

Choose: function Choose(f) {
    _callback = f;
    ...
}

Then when you're ready to call the callback function (I presume this is in onButtonOK/onButtonCancel), call the callback function using _callback(parameter);