1 00:00:00,620 --> 00:00:01,350 Welcome back. 2 00:00:01,609 --> 00:00:07,580 In the last year, we saw how we can add the entries to our second light database and now let's have 3 00:00:07,580 --> 00:00:09,700 a look at how we can retrieve them. 4 00:00:09,890 --> 00:00:13,280 And you already know how to do that if you followed along with the course. 5 00:00:13,280 --> 00:00:15,630 But let's still do that in this video. 6 00:00:15,650 --> 00:00:19,550 So where we are going to need that is in our main activity. 7 00:00:20,000 --> 00:00:21,710 But where we are going to. 8 00:00:22,700 --> 00:00:25,280 Pretty much created the function. 9 00:00:26,120 --> 00:00:32,479 In order to get all the happy places is going to be in our database handler, so here we have the function 10 00:00:32,479 --> 00:00:38,900 which creates the entry, but then let's create one function which will retrieve the entries. 11 00:00:40,300 --> 00:00:50,380 So I'm going to call this function Get Happy Places list, and it will return an array list of happy 12 00:00:50,380 --> 00:00:58,810 place models, so of our happy place there and now in there, I want to have the list. 13 00:00:58,990 --> 00:01:00,940 So I'm going to create the happy place list. 14 00:01:01,930 --> 00:01:06,220 Happy place, host of a realist. 15 00:01:07,780 --> 00:01:14,380 Happy place model, which will be and the list of happy place models. 16 00:01:15,920 --> 00:01:21,960 Of course, at that point, this would be redundant, so we already know that it's going to be a aerialists 17 00:01:21,980 --> 00:01:23,660 of happy place models, but still. 18 00:01:24,550 --> 00:01:27,340 As you can see, you can use both ways anyways. 19 00:01:27,730 --> 00:01:30,500 All right, then we need to have the Querrey. 20 00:01:30,500 --> 00:01:36,790 Do we want to run and to as we want to have all the entries, it's just going to be a very simple one. 21 00:01:36,790 --> 00:01:43,150 So I'm just going to say select star from our table. 22 00:01:43,960 --> 00:01:44,800 Happy place. 23 00:01:46,630 --> 00:01:50,800 So we're just going to get all the entries from our table then. 24 00:01:51,760 --> 00:01:57,790 We need to have a database that we can read from, so I'm just going to call it DBE, this DOT readable 25 00:01:57,790 --> 00:01:58,450 database. 26 00:01:59,690 --> 00:02:05,660 And then we will try to get the entries and of course, something can go wrong when you do that, so 27 00:02:05,840 --> 00:02:07,940 try and catch is always a good idea here. 28 00:02:08,180 --> 00:02:16,270 And I'm just going to add the catch plug here directly, which will potentially cause an SQLite exception. 29 00:02:19,350 --> 00:02:23,340 And if that happens, I want to catch that and I want to. 30 00:02:24,510 --> 00:02:27,180 Execute the sequel. 31 00:02:29,700 --> 00:02:31,770 Or the select query that we created here. 32 00:02:34,640 --> 00:02:37,940 And then just returned here and materialised. 33 00:02:38,510 --> 00:02:43,670 OK, so if nothing went as we expected it and just returned and materialist. 34 00:02:45,830 --> 00:02:52,640 And if everything worked, then I want to return my happy place list, so here, return a happy place. 35 00:02:53,120 --> 00:02:55,430 Now, of course, this list will be empty at that point. 36 00:02:55,440 --> 00:02:59,180 So we are currently returning an empty, happy place list. 37 00:02:59,340 --> 00:03:02,110 But now what we want to do is, of course, to fill this list. 38 00:03:02,420 --> 00:03:04,170 And what do we fill it with? 39 00:03:04,190 --> 00:03:10,130 Well, we fill it with all of the entries that we have from this happy place model style that we have 40 00:03:10,130 --> 00:03:10,460 here. 41 00:03:11,060 --> 00:03:14,960 But of course, we are going to need them in here. 42 00:03:15,620 --> 00:03:22,550 And we used to curser in order to go through every single entry that we have selected from our table. 43 00:03:23,090 --> 00:03:23,510 All right. 44 00:03:23,510 --> 00:03:27,920 So let's create this cursor, which will be of type cursor. 45 00:03:30,100 --> 00:03:32,050 And here we need to import coercer. 46 00:03:32,880 --> 00:03:40,890 All right, import it and then debe that rockery, so we run rockery, which is our select query query. 47 00:03:43,030 --> 00:03:48,310 Then we also need to pass in the selection arguments, and I'm just going to pass a no, because that's 48 00:03:48,310 --> 00:03:48,920 fine as well. 49 00:03:49,030 --> 00:03:52,750 We don't have any specific options that we want to set here. 50 00:03:54,890 --> 00:04:01,820 All right, and now we, first of all, move to the first entry of our curser, so the first vote, 51 00:04:01,970 --> 00:04:04,100 so to speak, so move to first. 52 00:04:06,150 --> 00:04:10,890 And if that works, then do the following, so run a do while loop. 53 00:04:11,750 --> 00:04:19,070 All right, so do while there are still entries, so Curser Dot moved to next. 54 00:04:20,329 --> 00:04:23,420 So this we say, OK, just run through the whole. 55 00:04:24,520 --> 00:04:31,390 List of entries that you have, so for every single entry that you have in the database that came from 56 00:04:31,390 --> 00:04:37,900 this select statement or the select query that we used here and then in here, what we do is we create 57 00:04:38,230 --> 00:04:38,800 places. 58 00:04:39,610 --> 00:04:42,870 So for every single entry, we create a new place. 59 00:04:43,180 --> 00:04:44,800 So for every iteration of our. 60 00:04:45,970 --> 00:04:52,100 So what I can do is I can create a new place which will be of type happy place model. 61 00:04:52,630 --> 00:04:58,990 Now, of course, our happy place model needs a lot of information, as we can see here, needs to ID 62 00:04:59,050 --> 00:05:02,110 need to title the image and so forth. 63 00:05:03,000 --> 00:05:08,890 OK, so in order to get those, what we can do is we can read it from the cursor so cursor get it. 64 00:05:09,410 --> 00:05:15,580 For example, if you want to get an integer cursor that gets column index and then you need to pass 65 00:05:15,580 --> 00:05:18,160 in the column index, which was our ID. 66 00:05:19,220 --> 00:05:25,430 And it has to be a string, of course, so in order to make sure that I'm using the right name, I go 67 00:05:25,430 --> 00:05:27,830 here to underscore ideia case. 68 00:05:27,830 --> 00:05:29,780 I have to be super careful here. 69 00:05:29,780 --> 00:05:34,970 So either I use underscore or I do it correctly and I use the name of the column. 70 00:05:35,520 --> 00:05:39,650 So our string that we created just for these purposes. 71 00:05:40,130 --> 00:05:47,180 OK, so that is something that is super important to keep in mind because especially with strings, 72 00:05:47,330 --> 00:05:48,410 things can go wrong. 73 00:05:48,440 --> 00:05:48,940 All right. 74 00:05:49,310 --> 00:05:53,540 So the first entry is we look at our ID here. 75 00:05:54,830 --> 00:05:59,270 OK, the key, Edem, then the next one is going to be. 76 00:06:00,630 --> 00:06:01,830 Our curser. 77 00:06:04,120 --> 00:06:14,200 Get string, and here it's Curser thought, get Collum index had the key title and so forth. 78 00:06:14,480 --> 00:06:18,420 OK, so we now need to do that for every single entry here. 79 00:06:19,030 --> 00:06:22,140 And of course I was missing the bracket there. 80 00:06:22,540 --> 00:06:29,860 So instead of me typing all of those cursor gets so-and-so, I'm just going to paste them in here. 81 00:06:31,540 --> 00:06:33,470 So it's going to be all of those. 82 00:06:34,090 --> 00:06:39,730 All right, so get string for the title, for the image, for the description, the date, the location, 83 00:06:39,730 --> 00:06:43,240 and then get double for the latitude and longitude. 84 00:06:44,270 --> 00:06:45,970 Hardened by this, we create a new place. 85 00:06:46,010 --> 00:06:47,090 Now, what is left to do? 86 00:06:47,510 --> 00:06:54,410 Well, what we want to return, we can see that here is going to be a happy place. 87 00:06:55,010 --> 00:06:56,600 So what is this happy place list? 88 00:06:57,820 --> 00:07:01,900 Well, it's a list of happy place models, so we just created a new happy place model. 89 00:07:01,930 --> 00:07:04,450 Now let's at this place that we just created. 90 00:07:05,720 --> 00:07:11,600 To our list, so here, happy list that ad plays. 91 00:07:14,330 --> 00:07:15,800 All right, I know. 92 00:07:17,190 --> 00:07:22,380 After all of that, we need to close our cursor so cursor dot close. 93 00:07:24,080 --> 00:07:27,680 So that our program doesn't run into any errors and problems. 94 00:07:31,130 --> 00:07:38,240 All right, so this is our helper method, which will allow us to get the place list now we need to 95 00:07:38,240 --> 00:07:44,270 have one in our main activity, which does the same thing pretty much, but on a slightly different 96 00:07:44,270 --> 00:07:44,580 level. 97 00:07:44,720 --> 00:07:50,980 So in our main activity, I also want to have a function which gets all of those happy places. 98 00:07:51,380 --> 00:07:52,940 So I'm going to create a new function here. 99 00:07:52,940 --> 00:07:59,300 Private Fun Get Happy Places list from local database. 100 00:08:01,160 --> 00:08:07,050 OK, so pretty long name, but that's it does it gets it from the local database, which is our Superflat. 101 00:08:07,370 --> 00:08:12,050 So here we need to create an object of our DB handler in order to call this function. 102 00:08:12,560 --> 00:08:17,660 OK, so this function that we just created, this happy place list. 103 00:08:19,490 --> 00:08:27,050 All right, so in order to do so, value Debe Handler, so I'm going to call it, will be a data base 104 00:08:27,500 --> 00:08:34,159 handler object and we need to pass in the context, which is this now we need to import database handler, 105 00:08:34,280 --> 00:08:38,150 even though it's a class that we use ourselves, but it's not in the same. 106 00:08:41,210 --> 00:08:42,150 Directory anymore. 107 00:08:42,500 --> 00:08:44,660 So if you look at it, you could see here. 108 00:08:46,030 --> 00:08:50,800 Database is in a different directory than our activities, than our main activity in this case, so 109 00:08:50,800 --> 00:08:57,890 we need to import it and you can see that it says, OK, it's inside of happy places, database, database, 110 00:08:57,940 --> 00:08:58,270 enter. 111 00:09:01,620 --> 00:09:07,860 So here I get or I create a happy place, a list. 112 00:09:10,890 --> 00:09:15,930 We're just going to be off type a realist happy place model. 113 00:09:19,040 --> 00:09:24,590 And what do I get that from from our DB Hunter that get happy price list? 114 00:09:27,510 --> 00:09:34,170 All right, so this is going to be our happy place list and it's going to be full already with all of 115 00:09:34,170 --> 00:09:34,770 the entries. 116 00:09:35,220 --> 00:09:42,510 So what we now need to do is we need to put all of those into a recycle of you because we want to display 117 00:09:42,510 --> 00:09:44,130 them a recycle you later on. 118 00:09:44,640 --> 00:09:48,990 But we don't have a recycle of UCLASS yet, so we will need to implement that later on. 119 00:09:49,230 --> 00:09:52,620 But for now, what I'm going to do so I'm just going to write it to the log. 120 00:09:53,070 --> 00:09:56,750 So I'm just going to say, if I get happy, place list is not empty. 121 00:09:57,360 --> 00:10:02,030 So the size is bigger than zero or greater than zero. 122 00:10:02,040 --> 00:10:05,460 If that's the case, then go through the whole list. 123 00:10:08,070 --> 00:10:17,070 And give me all of the values, so in here, I'm just going to say log dot e and here, just give me 124 00:10:17,070 --> 00:10:21,420 the title, which will be idot title. 125 00:10:22,780 --> 00:10:24,730 And of course, we need to import a lot here. 126 00:10:26,610 --> 00:10:31,850 There we are and now I'm going to keep it simple, I don't want to do that for all of the countries, 127 00:10:31,860 --> 00:10:38,420 OK, so I'm just going to say the title and maybe also the description and this will be idot description. 128 00:10:39,090 --> 00:10:44,430 So we're going through this for loop and I's going to be the happy place that we're currently looking 129 00:10:44,430 --> 00:10:44,700 at. 130 00:10:44,700 --> 00:10:49,080 And we just get the title of the happy place, currently looking at the standard description. 131 00:10:50,400 --> 00:10:55,620 And of course, at one point we'll need to call this function and I'm just going to call it in the uncreate 132 00:10:56,010 --> 00:10:56,450 method. 133 00:10:57,090 --> 00:11:00,060 OK, so in there, I'm just going to call it straight at the start. 134 00:11:00,310 --> 00:11:03,420 It should give me all of the happy places from the database. 135 00:11:04,650 --> 00:11:05,050 All right. 136 00:11:05,280 --> 00:11:06,480 At that point, we can test it. 137 00:11:06,690 --> 00:11:07,590 So let's do that. 138 00:11:10,250 --> 00:11:18,260 All right, so the activity started, let's look at our look and look for title and we can see title, 139 00:11:18,260 --> 00:11:20,900 test title, test title and test three. 140 00:11:21,300 --> 00:11:23,340 These were the three titles that I entered. 141 00:11:23,390 --> 00:11:28,820 And we have the description and you can see we have all three descriptions, test description, test 142 00:11:28,820 --> 00:11:33,550 description and then test the is June three. 143 00:11:34,170 --> 00:11:36,200 OK, so all of them are there. 144 00:11:36,290 --> 00:11:39,710 So now we can actually get the data from the database. 145 00:11:40,020 --> 00:11:41,150 OK, so that's it. 146 00:11:41,150 --> 00:11:47,150 In the next video, we are going to prepare to recycle you for the application to display all of that 147 00:11:47,150 --> 00:11:49,760 data in a readable manner, because currently it doesn't. 148 00:11:49,760 --> 00:11:50,060 Right. 149 00:11:50,450 --> 00:11:51,620 So so you in the next one.