refactor(visual-component): add markForCheck method

Author: nzbin

src/visual-component.ts

@@ -114,10 +114,10 @@ export class VisualComponent {
   noData?: boolean;
 
   /** 父组件 */
-  parent?: VisualComponent;
+  parent?: VisualComponent | null;
 
   /** 子组件 */
-  children?: VisualComponent[];
+  children?: VisualComponent[] | null;
 
   /** 显示 */
   show() {
@@ -222,4 +222,9 @@ export class VisualComponent {
   detectChanges() {
     this.changeDetectorRef.detectChanges();
   }
+
+  /** 标记变更检测 */
+  markForCheck() {
+    this.changeDetectorRef.markForCheck();
+  }
 }