How to get `mousedown` event on OpenLayers.Map?

javascript, openlayers

Solution

Add the 4th argument as `true`.

var events = map.events;
events.register("mousedown",map,function(e){
    console.log("mousedown");
    return true;
},true); // This argument is new

There are several event listeners already listening the `mousedown` event. One of them will eat the event when [map drag start] is detected, so the `mousedown` event will never reach the last listener.

Without the 4th argument, `events.register()` will add the listener to the end of the event-listening chain. With the 4th argument, it will add it to the first.

Problem

I'm using OpenLayers 2.13. I want to detect `mousedown`, `mousemove`, `mouseup` events while mouse is over `OpenLayers.Map`, so I wrote the following code. ``` var map = new OpenLayers.Map("map",{controls:[ new OpenLayers.Control.Navigation(), new OpenLayers.Control.ArgParser(), new OpenLayers.Control.Attribution() ]}); var events = map.events; events.register("mousedown",map,function(e){ console.log("mousedown"); }); events.register("mousemove",map,function(e){ console.log("mousemove"); }); events.register("mouseup",map,function(e){ console.log("mouseup"); }); ``` As a result, `mousemove` and `mouseup` is detected but no `mousedown`s. It says here that `mousemove` and `mouseup` is supported but `mousedown` is not. Is there any hacks I can apply to detect `mousedown` events without modifying OpenLayers script?

Original source