OpenLayers 2 – How to Set Custom Center and Zoom Level for Zoom World Icon

Question

OpenLayers Zoom Pan Control has a Zoom World Icon. When it is clicked the map zooms all the way out.

Is it possible to override this behavior and define a center and zoom level to which the map should be reset?

My Base Map is Bing Map

Answer 1

In order to do this without modifying the actual source code for openlayers (which you won't be doing if you're using a minified version, which by default you probably are), look at this answer.

However, I had to change it slightly for my code, which is using OpenLayers 2.11

OpenLayers.Control.PanZoom.prototype.buttonDown = function(evt) {
            var btn = evt.currentTarget ? evt.currentTarget : this;
            switch (btn.action) {
                case "panup": 
                    this.map.pan(0, -this.getSlideFactor("h"));
                    break;
                case "pandown": 
                    this.map.pan(0, this.getSlideFactor("h"));
                    break;
                case "panleft": 
                    this.map.pan(-this.getSlideFactor("w"), 0);
                    break;
                case "panright": 
                    this.map.pan(this.getSlideFactor("w"), 0);
                    break;
                case "zoomin": 
                    this.map.zoomIn(); 
                    break;
                case "zoomout": 
                    this.map.zoomOut(); 
                    break;
                case "zoomworld": 
                    alert("Hello world!");
                    break;
            }
        };

The only difference between this code and the one in the answer linked is that instead of onButtonClick, we're using buttonDown, and rather than evt.buttonElement, we're using evt.currentTarget

EDIT: Internet Explorer has no currentTarget property in their event handling. Luckily, we can use this instead. I have modified the code above accordingly. For an explanation of this, please see this article. A relevant stackoverflow question is here.