MouseWheel in Chrome and Firefox

Question

I\'m trying to handle the mouseWheel event in an advancedDataGrid with not success. Without any additional code my adg can be scrolled with the mouse in IE but not in firefo

Answer 1

Fix for no MouseWheel in a Flex app when wmode="opaque" (it actually works in IE, just not Firefox or Chrome, probably not Safari or Opera either). This also fixes the different MouseWheel scroller rates between Firefox and everything else.

Add this JavaScript to your wrapper: .

        if(window.addEventListener) {
            var eventType = (navigator.userAgent.indexOf('Firefox') !=-1) ? "DOMMouseScroll" : "mousewheel";            
            window.addEventListener(eventType, handleWheel, false);
        }

        function handleWheel(event) {
            var app = document.getElementById("YOUR_APPLICATION");
            var edelta = (navigator.userAgent.indexOf('Firefox') !=-1) ? -event.detail : event.wheelDelta/40;                                   
            var o = {x: event.screenX, y: event.screenY, 
                delta: edelta,
                ctrlKey: event.ctrlKey, altKey: event.altKey, 
                shiftKey: event.shiftKey}

            app.handleWheel(o);
        }

And drop this support class into your main MXML file (Declarations for Flex4): .

package {
import flash.display.InteractiveObject;
import flash.display.Shape;
import flash.display.Stage;
import flash.events.MouseEvent;
import flash.external.ExternalInterface;
import flash.geom.Point;

import mx.core.FlexGlobals;
import mx.core.UIComponent;
import mx.events.FlexEvent;

public class MouseWheelSupport {

    //--------------------------------------
    //   Constructor 
    //--------------------------------------

    public function MouseWheelSupport() {
        FlexGlobals.topLevelApplication.addEventListener(FlexEvent.APPLICATION_COMPLETE, attachMouseWheelHandler);
    }

    //------------------------------------------------------------------------------
    //
    //   Functions  
    //
    //------------------------------------------------------------------------------

    //--------------------------------------
    //   Private 
    //--------------------------------------

    private function attachMouseWheelHandler(event : FlexEvent) : void {
        ExternalInterface.addCallback("handleWheel", handleWheel);
    }

    private function handleWheel(event : Object) : void {
        var obj : InteractiveObject = null;
        var applicationStage : Stage = FlexGlobals.topLevelApplication.stage as Stage;

        var mousePoint : Point = new Point(applicationStage.mouseX, applicationStage.mouseY);
        var objects : Array = applicationStage.getObjectsUnderPoint(mousePoint);

        for (var i : int = objects.length - 1; i >= 0; i--) {
            if (objects[i] is InteractiveObject) {
                obj = objects[i] as InteractiveObject;
                break;
            }
            else {
                if (objects[i] is Shape && (objects[i] as Shape).parent) {
                    obj = (objects[i] as Shape).parent;
                    break;
                }
            }
        }

        if (obj) {
            var mEvent : MouseEvent = new MouseEvent(MouseEvent.MOUSE_WHEEL, true, false,
                                                     mousePoint.x, mousePoint.y, obj,
                                                     event.ctrlKey, event.altKey, event.shiftKey,
                                                     false, Number(event.delta));
            obj.dispatchEvent(mEvent);
        }
    }
}
}

JavaScript example:.