fix: fixed memory leaks in scale and viewport model

src/chart/components/y_axis/y-axis-scale.handler.ts

@@ -32,12 +32,12 @@ export class YAxisScaleHandler extends ChartBaseElement {
 
 	constructor(
 		private bus: EventBus,
-		config: YAxisConfig,
+		private config: YAxisConfig,
 		panning: ChartPanComponent,
 		private scale: ScaleModel,
-		canvasInputListener: CanvasInputListenerComponent,
+		private canvasInputListener: CanvasInputListenerComponent,
 		private bounds: CanvasBoundsContainer,
-		hitTest: HitBoundsTest,
+		private hitTest: HitBoundsTest,
 		private autoScaleCallback: (auto: boolean) => void,
 	) {
 		super();
@@ -58,13 +58,17 @@ export class YAxisScaleHandler extends ChartBaseElement {
 				},
 			);
 			this.addChildEntity(dragNDropYComponent);
+		}
+	}
 
-			if (config.customScaleDblClick) {
-				canvasInputListener.observeDbClick(hitTest).subscribe(() => {
-					autoScaleCallback(true);
+	protected doActivate(): void {
+		if (this.config.customScaleDblClick) {
+			this.addRxSubscription(
+				this.canvasInputListener.observeDbClick(this.hitTest).subscribe(() => {
+					this.autoScaleCallback(true);
 					this.bus.fireDraw();
-				});
-			}
+				}),
+			);
 		}
 	}
 

src/chart/model/scale.model.ts

@@ -55,7 +55,7 @@ type Constraints = (initialState: ViewportModelState, state: ViewportModelState)
 export class ScaleModel extends ViewportModel {
 	public scaleInversedSubject: Subject<boolean> = new Subject<boolean>();
 	// y-axis component needs this subject in order to halt prev animation if axis type is percent
-	public beforeStartAnimationSubject = new Subject<void>();
+	public beforeStartAnimationSubject: Subject<void> = new Subject<void>();
 
 	// TODO rework, make a new history based on units
 	history: ScaleHistoryItem[] = [];
@@ -84,13 +84,22 @@ export class ScaleModel extends ViewportModel {
 	}
 
 	protected doActivate(): void {
+		super.doActivate();
+		this.scaleInversedSubject = new Subject();
+		this.beforeStartAnimationSubject = new Subject();
 		this.addRxSubscription(
 			this.scaleInversedSubject.subscribe(() => {
 				this.fireChanged();
 			}),
 		);
 	}
 
+	protected doDeactivate(): void {
+		super.doDeactivate();
+		this.scaleInversedSubject.complete();
+		this.beforeStartAnimationSubject.complete();
+	}
+
 	/**
 	 * The method adds a new "constraint" to the existing list of x-axis constraints for charting.
 	 * The "constraint" is expected to be an object containing information about the constraints, such as the minimum and maximum values for the x-axis.

src/chart/model/scaling/viewport.model.ts

@@ -152,6 +152,16 @@ export abstract class ViewportModel extends ChartBaseElement implements Viewable
 		share(),
 	);
 	//endregion
+
+	protected doActivate(): void {
+		super.doActivate();
+		this.changed = new Subject();
+	}
+
+	protected doDeactivate(): void {
+		super.doDeactivate();
+		this.changed.complete();
+	}
 	//region conversion methods
 	/**
 	 * Converts a unit value to pixels based on the current zoom level and xStart value.
@@ -217,10 +227,7 @@ export abstract class ViewportModel extends ChartBaseElement implements Viewable
 			return pixelsToUnits(normalizedPx + unitToPixels(this.yStart, this.zoomY), this.zoomY);
 		} else {
 			// inverse by default because canvas calculation [0,0] point starts from top-left corner
-			return pixelsToUnits(
-				bounds.height - normalizedPx + unitToPixels(this.yStart, this.zoomY),
-				this.zoomY,
-			);
+			return pixelsToUnits(bounds.height - normalizedPx + unitToPixels(this.yStart, this.zoomY), this.zoomY);
 		}
 	}