Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Java Java Data Structures - Retired Efficiency! Changing Course

didn't 'add' the new video to the List

Can't figure out why adding gets me a compiler error....

com/example/model/Course.java
package com.example.model;

import java.util.List;

public class Course {
  private String mName;
  private List<Video> mVideos; 

  public Course(String name, List<Video> videos) {
    mName = name;
    mVideos = videos;
  }

  public String getName() {
    return mName;
  }

  public List<Video> getVideos() {
    return mVideos;
  }

}
com/example/model/Video.java
package com.example.model;

public class Video {
  private String mTitle;

  public Video(String title) {
    mTitle = title;
  }

  public String getTitle() {
    return mTitle;
  }

  public void setTitle(String title) {
    mTitle = title;
  }

}
QuickFix.java
import com.example.model.Course;
import com.example.model.Video;

import java.util.Map;

public class QuickFix {

  public void addForgottenVideo(Course course) {
    // TODO(1):  Create a new video called "The Beginning Bits"
    String forgottenVid = "The Beginning Bits";
    // TODO(2):  Add the newly created video to the course videos as the second video.
    mVideos.add(forgottenVid);
  }

  public void fixVideoTitle(Course course, String oldTitle, String newTitle) {

  }

  public Map<String, Video> videosByTitle(Course course) {
    return null;
  }

}

1 Answer

Kourosh Raeen
Kourosh Raeen
23,733 Points

For the first TODO you need to create a new video object, but you're creating a String. Use the constructor of the Video class:

Video video = new Video("The Beginning Bits");

For the second TODO, mVideos is a private member variable of a different class and you don't have access to it. You need to call the getVideos() method on the course passed in. Also, you need to pass in the index to the add() method so that the video will be the the second one in the list:

course.getVideos().add(1, video);

I had a dumb. I figured it out. Thanks!