jquery plugin doesn't work?

[mrbean]

Here is the plugin code:

function textTyping_animation(text,location,speed){
    var progress = 0;
    var a = setInterval(function(){
        progress++;
        document.getElementById(location).innerHTML = text.substring(0,progress);
        if(progress == text.length){
            clearInterval(a);
        }
    },speed);
};
(function($){
    $.fn.textAnim = function(text,speed){
        var progress = 0;
        var a = setInterval(function(){
            progress++;
            $(this).html(text.substring(0,progress));
            if(progress == text.length){
                clearInterval(a);
            }
        },speed);
    };
})(jQuery);

Here is the execution:

$(document).ready(function(){
    starttext = function()
    {
        document.getElementById("textbox").style.display = "block";
        //textTyping_animation("Dit is een dummy text!","textbox_inner",70);
        //game.output("klaar");
            $("#textbox_inner").textAnim("Dit is een dummy text!",70);
    }
});

Html load code:

    <script type="text/javascript" language="javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js" ></script>
    <script type="text/javascript" language="javascript" src="js/jqueryplugins.js" ></script>
    <script type="text/javascript" language="javascript" src="js/libraries/gamelibrary.js"></script>

textTyping_animation(); Works, but .textAnim not

[devnull69]

Your problem is a scope switch. So inside the setInterval loop "this" will no longer refer to your jQuery object but rather to the "window" object. A workaround would be to store the reference and use this temporary variable instead of "this" inside setInterval

(function($){
    $.fn.textAnim = function(text,speed){
        var progress = 0;
        var that = this;
        var a = setInterval(function(){
            progress++;
            $(that).html(text.substring(0,progress));
            if(progress == text.length){
                clearInterval(a);
            }
        },speed);
    };
})(jQuery);

[mrbean]

Thank you!