root / trunk / src / lfx / scroll.js

dojo.provide("dojo.lfx.scroll");
dojo.require("dojo.html.util");
dojo.require("dojo.html.iframe");
dojo.require("dojo.lfx.Animation");

dojo.lfx.smoothScroll = function(/*DOMNode*/ node,
                                                                                        /*Window*/ win,
                                                                                        /*Object*/offset,
                                                                                        /*int?*/ duration,
                                                                                        /*function?*/ easing,
                                                                                        /*Object?*/ handlers){
        // summary: Returns an animation that will smooth-scroll to a node (specified in setup())
        // description: This implementation support either horizental or vertical scroll, as well as
        //              both. In addition, element in iframe can be scrolled to correctly.
        // offset: {x: int, y: int} this will be added to the target position
        // duration: Duration of the animation in milliseconds.
        // easing: An easing function.
        // handlers: { handler: Function?, onstart: Function?, onstop: Function?, onanimate: Function? }

        var targs = {
                "window": win,
                "offset": offset || {x:0,y:0},
                "target": dojo.html.getAbsolutePositionExt(node,true,dojo.html.boxSizing.BORDER_BOX, win),
                "duration": duration,
                "easing": easing||dojo.lfx.easeOut
        };

        var anim = new dojo.lfx.Animation({
                        beforeBegin: function(){
                                var current = dojo.withGlobal(targs.window,dojo.html.getScroll).offset;
                                delete this.curve;
                                anim.curve = new dojo.lfx.Line([current.x,current.y],[targs.target.x+targs.offset.x,targs.target.y+targs.offset.y]);
                        },
                        onAnimate: function(value){
                                targs.window.scrollTo(value[0],value[1]);
                        }
                },
                duration, 
                null, //curve, will be set in scrollTo
                easing||dojo.lfx.easeOut
        );
        if(handlers){
                for(var x in handlers){
                        if(dojo.lang.isFunction(handlers[x])){
                                anim.connect(x, anim, handlers[x]);
                        }
                }
        }

        return anim; // dojo.lfx.Animation
}