WEBVTT 00:00.080 --> 00:00.960 Welcome back. 00:01.000 --> 00:02.440 We finished everything. 00:02.440 --> 00:05.760 Now let's call the camera screen in our main activity. 00:05.760 --> 00:08.240 So here main activity file. 00:08.280 --> 00:11.280 Remove the greeting composables. 00:11.280 --> 00:16.680 And here remove the scaffold and the gadget app screen okay. 00:16.920 --> 00:21.440 Inside the set content let's start building our application. 00:21.440 --> 00:23.560 Start with surface. 00:23.760 --> 00:33.400 Set the modifier fill maximum size material theme, color scheme, dot background and var has camera 00:33.400 --> 00:34.320 permission. 00:34.320 --> 00:37.080 We need to check for camera permissions by. 00:37.120 --> 00:37.960 Remember. 00:38.000 --> 00:41.280 Let me add this in the manifest. 00:41.280 --> 00:48.480 So here inside the manifest we need to add the permissions uses permission internet. 00:48.520 --> 00:53.240 You can access the internet the camera the external storage. 00:53.400 --> 01:03.640 You can read the read write and so on okay we need to add the That uses features so Alt plus enter to 01:03.680 --> 01:06.200 solve this add uses feature. 01:06.240 --> 01:14.040 You see guys that whenever you need to use a hardware from the phone, we need to add uses feature and 01:14.040 --> 01:16.720 set the hardware in this type. 01:16.720 --> 01:19.080 In this application we need to use the camera. 01:19.120 --> 01:29.640 You can use low latency Bluetooth camera or fingerprint, geolocation, microphone, NFS, NFC and others. 01:29.640 --> 01:32.440 We need to use the camera and set it like this. 01:32.480 --> 01:38.360 Okay, you can also remove the internet permission okay, so we need just the camera. 01:38.360 --> 01:41.680 And the camera uses features okay. 01:41.920 --> 01:49.520 So those are the camera permissions that we need to add in the manifest back to the main activity here. 01:49.680 --> 01:59.120 Let me continue with has permission Alt plus enter to import the Remember and Alt Plus enter to add 01:59.240 --> 01:59.840 by. 01:59.880 --> 02:10.040 Okay, start with mutable state of context compat dot check self permission. 02:10.080 --> 02:19.200 We need to check if there is a permission for the camera manifest, dot permission dot camera and if 02:19.320 --> 02:26.640 this equals to the package manager dot permission granted. 02:26.640 --> 02:31.320 Here we are checking if we have a camera permission. 02:31.320 --> 02:35.480 Import the operator mutable state, dot set and alt plus. 02:35.480 --> 02:39.360 Enter again just to import the operator state dot get value. 02:39.360 --> 02:40.320 And here we go. 02:40.520 --> 02:44.840 So this variable is used to check if there is granted. 02:44.840 --> 02:55.680 If the permissions of the camera are granted or not then val launcher equals to remember launcher for 02:55.680 --> 03:04.960 activity result and set the contract as activity contracts result, contracts dot request permission 03:04.960 --> 03:11.240 and if the result is granted, go and set the has permission to is granted. 03:11.240 --> 03:13.320 I want from you to focus with me. 03:13.360 --> 03:15.920 We used this new method. 03:15.920 --> 03:18.800 This is the first time we used in our application. 03:18.800 --> 03:21.520 Remember launcher for activity result. 03:21.520 --> 03:26.240 This creates a launcher that survives Recompositions. 03:26.240 --> 03:36.040 Why needed permission requests are asynchronous and need stable reference without remember would recreate 03:36.040 --> 03:41.160 launcher on recomposition losing the permission request callback. 03:41.680 --> 03:44.520 The first parameter is the contract. 03:44.560 --> 03:45.760 The first parameter. 03:45.800 --> 03:55.400 The contract defines what type of activity result we are requesting on the request permission function, 03:55.400 --> 03:58.200 specifically for requesting a single permission. 03:58.230 --> 04:00.310 So other common contracts. 04:00.310 --> 04:04.550 We can use your request multiple permissions for multiple permissions. 04:04.550 --> 04:10.150 If we have like a camera read and write external storage and so on. 04:10.350 --> 04:15.750 But since we are using a single permission, we used request permission. 04:15.750 --> 04:22.910 Also, we can set the on contract to request multiple permissions, create document, get content capture 04:22.910 --> 04:30.870 video, open document, pick contact, pick picture for taking photos, for contact selection, pick 04:30.870 --> 04:32.830 contact and so on. 04:32.830 --> 04:42.310 Okay, so there are a lot of contents we can use on a result executed when the user responds to permission. 04:42.310 --> 04:52.270 Dialog granted Boolean indicating if permission was granted and update state has camera permission set 04:52.270 --> 04:54.150 it to granted is granted. 04:54.390 --> 05:01.710 Updates the UI state since this the the has a camera permission is a variable that we created before 05:01.870 --> 05:05.790 and being updated here in the on results callback. 05:05.990 --> 05:10.870 Then after this we need to use a launcher effect. 05:10.870 --> 05:21.950 As I told you before, launch effect set it to true key number one and if not has camera permission. 05:21.950 --> 05:28.230 What we need to do, we need to request from the user a launcher for manifest camera. 05:28.270 --> 05:31.830 Here we need to check if the user if there's not a. 05:31.870 --> 05:40.510 Granted that camera permissions go and set and launch the camera manifest request from the user. 05:40.630 --> 05:49.630 If the if has camera permission, we need to load the camera screen that we created before okay. 05:50.110 --> 05:52.350 This is our application. 05:52.350 --> 05:57.830 This is how we handle the camera permissions for our application.