How can I delete a feature after a callback on openlayers - maps

Question

I try to create a code who can create a feature and delete it if it dosen't respect some rules. (in this exemple I just delete it just after his creation)
Below is my code, I create a map and I allow to create a polygon on. Next I try to delete it when an event drawend is triggered.
init(){
this.message = "";
var raster = new TileLayer({
source: new XYZ({
url: 'http://mt1.google.com/vt/lyrs=m&x={x}&y={y}&z={z}',
attributions: [
'© Google','Terms of Use.'
]
})
});
this.source = new VectorSource();
this.vector = new VectorLayer({
source: this.source
});
this.map = new Map({
layers: [raster, this.vector],
target: 'map',
view : new View({
center: [0,0],
zoom : 4
})
});
this.addInteraction();
}
addInteraction() {
var self = this;
this.draw = new Draw({
source: this.source,
type: "Polygon"
});
this.draw.on('drawend', function (e) {
self.message = "";
self.map.removeInteraction(self.draw);
self.selectedFeature = e.feature;
self.removeSelectedFeature();
// This works but I don't like this solution
//setTimeout(function(){self.removeSelectedFeature()}, 1);
self.geoJSON = self.getCoord();
});
this.map.addInteraction(this.draw);
}
removeSelectedFeature()
{
this.source.removeFeature(this.selectedFeature);
this.selectedFeature = null;
this.validated = false;
this.addInteraction();
}
but When I try to execute this code, I got this error :
core.js:14597 ERROR TypeError: Cannot read property 'forEach' of undefined
at VectorSource.removeFeatureInternal (Vector.js:951)
at VectorSource.removeFeature (Vector.js:939)
at MapComponent.push../src/app/map/map.component.ts.MapComponent.removeSelectedFeature (map.component.ts:106)
at Draw.<anonymous> (map.component.ts:97)
at Draw.boundListener (events.js:41)
at Draw.dispatchEvent (Target.js:99)
at Draw.finishDrawing (Draw.js:872)
at Draw.handleUpEvent (Draw.js:578)
at Draw.handleEvent (Pointer.js:132)
at Draw.handleEvent (Draw.js:524)
I know it's because my feature isn't exist yet, and it will created after the event will finish. hence my question, how can I delete a feature after it was created ?
I tried using a event button but it's not a good idea I would like that the user don't need to click on a button for execute checks.
I tried using a setTimeout (as we can see in my commented code) but I don't like this solution (even if it works)
Anyone can explain me how can I do the job ?
Thanks in advance ;)

Answer 1

have you tried something like this in your drawend, if your check failed:
source.once('addfeature', (event) => {
const feature = event.feature;
source.removeFeature(feature);
});
this listens to the 'addfeature' event once and then removes the listener.