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Not able to remove EventListener in Typescript

Time:01-05

I am trying to remove an eventlistener in typescript. I am adding eventlisteners in an if-statement. In the else-statement I am trying to remove these eventlisteners, but for some reason it does not remove them.

FYI: I have a button where I set a boolean (movePick). If it is true then I want to be able to Move my Object. Thats where the eventlisterners are created. If I click the button again I should not be able to move the object anymore. That's why I am trying to remove the eventlisteners.

public moveObject(movePick: boolean, raycaster: THREE.Raycaster): void {
        const plane = new THREE.Plane();
        const pNormal = new THREE.Vector3(0, 1, 0); // plane's normal
        const planeIntersect = new THREE.Vector3(); // point of intersection with the plane
        const pIntersect = new THREE.Vector3(); // point of intersection with an object (plane's point)
        const shift = new THREE.Vector3(); // distance between position of an object and points of intersection with the object
        let isDragging = false;
        let dragObject: any;
        // events

        const pointermove = (event: PointerEvent) => {
            const rect = this.canvas.getBoundingClientRect();
            const x = event.clientX - rect.left
            const y = event.clientY - rect.top
            const pickPosition = { x: 0, y: 0 };
            pickPosition.x = (x / this.canvas.clientWidth) * 2 - 1;
            pickPosition.y = (y / this.canvas.clientHeight) * -2   1;
            raycaster.setFromCamera(pickPosition, this.camera);
            // console.log("movePICK IN POINTERMOVE",movePick)
            if (isDragging) {
                raycaster.ray.intersectPlane(plane, planeIntersect);
                dragObject.position.addVectors(planeIntersect, shift);
            }
        }

        const mousedown = () => {
            const intersects = raycaster.intersectObjects(this.scene.children);

            for (let i = 0; i < this.mesharr.length; i  ) {
                if (intersects[0].object.name == this.mesharr[i].name && intersects[0].object.name != "Rail") {
                    pIntersect.copy(intersects[0].point);
                    plane.setFromNormalAndCoplanarPoint(pNormal, pIntersect);
                    shift.subVectors(intersects[0].object.position, intersects[0].point);
                    isDragging = true;
                    dragObject = intersects[0].object;
                }
            }
        }

        const pointerup = () => {
            isDragging = false;
            dragObject = null;
        }
        **if (movePick) {
            document.addEventListener("pointermove", pointermove);
            document.addEventListener("mousedown", mousedown);
            document.addEventListener("pointerup", pointerup);
        } else {
            document.removeEventListener("pointermove", pointermove);
            document.removeEventListener("mousedown", mousedown);
            document.removeEventListener("pointerup", pointerup);
        }**
    }

If I remove the eventlisternes in the same if-statement that I added them in, they get removed. But if the button is clicked again and it enters the else-statement then they can not be removed. I also tried several solutions in stackoverflow but none of them would work.

CodePudding user response:

Save the instances of the events to the class field and then call the instance in removeEventListener eg.

 document.removeEventListener("pointermove", this.savedpointermove); 

and now it should work

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