1 00:00:05,020 --> 00:00:09,320 Let's go over the solution to the challenge I discussed in the last video. 2 00:00:09,320 --> 00:00:12,680 How did you get on with it though? Did you manage to change the code, to let the 3 00:00:12,680 --> 00:00:16,219 user go back to the list of albums without choosing a song? Well there's 4 00:00:16,219 --> 00:00:19,759 only a couple changes to be made. At the moment, we're breaking out of the loop, 5 00:00:19,759 --> 00:00:24,230 and you can see that on line 25. Now we don't want to do that, so what we're 6 00:00:24,230 --> 00:00:31,809 going to do is delete the break and the else, that its in - so these two. Delete those. 7 00:00:31,809 --> 00:00:37,130 So now on line 25, we display the title of the song. If no song's been chosen, 8 00:00:37,130 --> 00:00:42,600 we don't want to do that. In fact, my IDE, if we hover over title, 9 00:00:42,600 --> 00:00:47,540 is giving me a warning. It says Name Title can be not defined. If no song is selected, 10 00:00:47,540 --> 00:00:52,420 title won't have a value. So we can fix that there, by indenting line 25, 11 00:00:52,420 --> 00:00:59,020 to make it part of the if block. So I can come down here, indent it. Now, although it 12 00:00:59,030 --> 00:01:02,840 doesn't matter to Python, we can make the code a bit more readable by moving 13 00:01:02,840 --> 00:01:08,660 line 25 up a line. Control shift up will do that, on Windows, as well as Linux, 14 00:01:08,660 --> 00:01:14,340 and I think it might be command shift up, but you can check your bindings on a Mac, if you need to. 15 00:01:14,340 --> 00:01:19,320 By doing that, it makes it pretty obvious that line 26 isn't part of the if block, 16 00:01:19,320 --> 00:01:24,100 and that's literally all the changes we need to make. To confirm this, though, 17 00:01:24,100 --> 00:01:29,240 let's test the program again, so I'm going to run it. This time I'm going 18 00:01:29,240 --> 00:01:34,729 to select option 2, Bad Company. That displays the songs on the Bad Company 19 00:01:34,729 --> 00:01:38,980 album. First thing I want to do is test that I haven't broken anything. 20 00:01:38,980 --> 00:01:43,320 So selecting option 2, should play the track Rock Steady. Let me do that - 21 00:01:43,320 --> 00:01:48,480 playing Rock Steady, so that's working, and we get the albums list again, as well. 22 00:01:48,480 --> 00:01:52,500 And what I'll do, just to make sure that, if you're watching this with subtitles, 23 00:01:52,500 --> 00:01:56,570 you can see it. I'm going to change the View Mode to Window. We've still 24 00:01:56,570 --> 00:01:59,600 got the output, from what we've been running in this session, so far. 25 00:01:59,600 --> 00:02:05,240 So I'm going to choose option 3, for Nightflight. This time I'm going to make an 26 00:02:05,240 --> 00:02:10,850 invalid choice - I want to select 0, or type in 0. As you can see, no song's 27 00:02:10,850 --> 00:02:16,320 played, and we get the albums menu again. Now we're back to the album's menu. 28 00:02:16,320 --> 00:02:21,540 I can select 0 or another invalid choice, and the program exits, as you can see. 29 00:02:21,540 --> 00:02:26,560 So make sure you test it more thoroughly, to make sure it behaves well with all valid options. 30 00:02:26,560 --> 00:02:30,420 At the very least, you should test the first and last valid choices 31 00:02:30,420 --> 00:02:34,820 in each list, and a choice from the middle of the lists. The first and last options 32 00:02:34,820 --> 00:02:40,760 count as edge cases, and it's very important to test edge cases. So if your 33 00:02:40,760 --> 00:02:45,720 solution behaves the same, then well done - you've completed the challenge. 34 00:03:59,060 --> 00:04:02,100 See you in the next video.