WEBVTT 00:00.080 --> 00:02.420 And here is yet another activity. 00:02.420 --> 00:05.720 And with this we will finish this section on Gpio. 00:06.020 --> 00:11.660 So the goal of this activity is to make the code that we did in activity six. 00:11.660 --> 00:15.200 So we're just going to take the same code we did in the last video. 00:15.230 --> 00:18.710 We're going to take this code and we're going to make it more dynamic. 00:18.710 --> 00:24.260 So the goal is to be able to use this code for any amount of LEDs. 00:24.260 --> 00:25.880 So we have three LEDs. 00:25.880 --> 00:28.490 But now what if you have five LEDs. 00:28.490 --> 00:32.450 You see that with this you will need to modify the code a lot. 00:32.450 --> 00:35.090 And you will need to add a lot of lines. 00:35.120 --> 00:35.450 Okay. 00:35.480 --> 00:41.480 So if you want to have the same code working for two LEDs or five LEDs, well you will need to do some 00:41.480 --> 00:42.410 improvements here. 00:42.410 --> 00:46.400 So for this activity number seven we will not add any hardware. 00:46.400 --> 00:48.980 We will not add any new functionality. 00:49.010 --> 00:52.400 We will just work on the existing code and improve it. 00:52.430 --> 00:56.570 What I will do is I will just uh well you have the activity six. 00:56.600 --> 01:00.590 I'm just going to save it as activity seven. 01:01.370 --> 01:01.940 All right. 01:01.940 --> 01:03.830 So that's the new activity. 01:03.860 --> 01:06.560 We're going to start from the same code and improve it. 01:06.560 --> 01:08.450 And what will we do. 01:08.480 --> 01:15.720 Well here we will work with lists So I have my three LEDs and I'm just going to start with this. 01:15.720 --> 01:17.850 I'm going to give you that tip. 01:17.880 --> 01:21.120 You can start an LED list like that. 01:21.120 --> 01:24.720 And in this you will put three variables. 01:24.720 --> 01:27.570 Actually you will not just put integers or strings. 01:27.570 --> 01:31.020 You will put actual variables here that we have created before. 01:31.020 --> 01:34.890 So led one LED two, LED three. 01:34.920 --> 01:35.250 All right. 01:35.280 --> 01:36.780 You create the three LEDs. 01:36.780 --> 01:39.750 You put them inside a list. 01:39.750 --> 01:41.520 And then what can you do in this program. 01:41.520 --> 01:45.060 Well first of all you see that we initialize all LEDs. 01:45.060 --> 01:47.970 So we set the initial state to off. 01:47.970 --> 01:49.230 So turn off the LEDs. 01:49.230 --> 01:51.840 You can start by well using this list. 01:51.840 --> 01:58.350 And with a for loop, you can go through each element of the list and turn off the LEDs. 01:58.350 --> 02:01.410 Then we will keep this LED index. 02:01.410 --> 02:08.100 And we will also keep the last here two lines of the code okay, so when the button is pressed we will 02:08.100 --> 02:10.470 call the switch LED function. 02:10.470 --> 02:14.040 But there will be some work in this function. 02:14.070 --> 02:14.460 All right. 02:14.460 --> 02:21.960 So instead of saying zero, one two etc. we want to have something that's more dynamic. 02:21.960 --> 02:28.470 So the biggest part of the challenge is to find out what to do here so that we can work with this list. 02:28.470 --> 02:35.430 And basically for each index, we want to turn off all LEDs and turn one only one LEDs. 02:35.430 --> 02:37.290 So that's what you need to implement here. 02:37.290 --> 02:43.110 And for this you will need to know actually the length of the LED list. 02:43.110 --> 02:45.480 So you will need to get that into your program. 02:45.510 --> 02:47.520 I'm just going to give it to you here. 02:47.550 --> 02:48.930 I'm just going to write it here. 02:48.930 --> 02:54.720 If you want to get the length of a list, you can do l e n Len. 02:54.750 --> 02:58.980 You can see the syntax highlighting of for example LED list. 03:00.390 --> 03:06.660 So if I would just print this with that list it will return three because we have three elements. 03:06.690 --> 03:06.960 All right. 03:06.960 --> 03:12.120 So this is a function we're going to use in the solution that I haven't talked about before. 03:12.120 --> 03:13.500 So I give it to you now. 03:13.500 --> 03:16.710 And well I will see you in the next video for the solution. 03:16.710 --> 03:22.170 You might feel a bit lost now I know it's definitely a bit more challenging, but try to do as much 03:22.170 --> 03:23.250 as possible, okay? 03:23.280 --> 03:24.900 Try to find solutions. 03:24.900 --> 03:31.020 Try to find ways to solve this problem, and then you can watch the solution and maybe also try again 03:31.020 --> 03:32.160 in a few days.