Edit logic components of comment

src/app/comment/comment.component.ts

-import { Component, OnInit } from '@angular/core';
+import { Component, Input, OnInit } from '@angular/core';
+import { ActivatedRoute } from '@angular/router';
+import { Location } from '@angular/common';
 import { Comment } from '../comment';
+import { CommentService} from '../comment.service';
+import { RoomService } from '../room.service';
 
 @Component({
   selector: 'app-comment',
@@ -9,9 +13,32 @@ import { Comment } from '../comment';
 export class CommentComponent implements OnInit {
   comments: Comment[];
 
-  constructor() { }
+  constructor(
+    private route: ActivatedRoute,
+    private roomService: RoomService,
+    private location: Location,
+    private commentService: CommentService) { }
 
   ngOnInit() {
+    this.route.params.subscribe(params => {
+      this.getRoom(params['roomId']);
+    });
   }
 
+  getRoom(id: string): void {
+    this.roomService.getRoom(id).subscribe(
+      params => {
+        this.getComments(params['id']);
+      }
+    );
+  }
+
+  getComments(roomId: string): void {
+    this.commentService.getComments(roomId)
+      .subscribe(comments => this.comments = comments);
+  }
+
+  goBack(): void {
+    this.location.back();
+  }
 }

src/app/create-comment/create-comment.component.ts

-import {Component, OnInit, Input, Inject} from '@angular/core';
+import { Component, OnInit, Input } from '@angular/core';
 import { ActivatedRoute } from '@angular/router';
 import { Location } from '@angular/common';
 import { Room } from '../room';
@@ -6,7 +6,6 @@ import { Comment } from '../comment';
 import { RoomService } from '../room.service';
 import { CommentService} from '../comment.service';
 import { NotificationService } from '../notification.service';
-import { MAT_DIALOG_DATA, MatDialogRef } from '@angular/material';
 
 @Component({
   selector: 'app-create-comment',