1 00:00:00,180 --> 00:00:04,260 So as you can see here these are the lines of code that I actually pasted here. 2 00:00:04,410 --> 00:00:11,660 So first what I want to actually instantiate this database handler object that I declared in line 25 3 00:00:11,700 --> 00:00:14,310 as you can see here I declared an object of type. 4 00:00:14,310 --> 00:00:15,560 Why is your handler. 5 00:00:15,750 --> 00:00:18,340 And first of all I want to instantiate that object. 6 00:00:18,420 --> 00:00:21,650 So database handler assignment operator new. 7 00:00:21,900 --> 00:00:25,780 My to light my light handler. 8 00:00:26,130 --> 00:00:28,850 And as an argument we need to pass the context. 9 00:00:29,010 --> 00:00:34,440 So the context is this class main activity that this at 11:52 as you can see here. 10 00:00:34,530 --> 00:00:38,760 I actually want to instantiate this all computerless objects. 11 00:00:38,760 --> 00:00:44,540 So as you can see here I declared this object which is of type list as you can see here. 12 00:00:44,730 --> 00:00:50,850 So remember that list is actually an interface which had not actually created directly an object of 13 00:00:50,850 --> 00:00:51,590 type list. 14 00:00:51,630 --> 00:00:57,550 OK so we need to instantiate this list object by using the Aurelia's class. 15 00:00:57,600 --> 00:00:58,050 OK. 16 00:00:58,200 --> 00:01:05,490 But this list interface has more actually more methods and we can use those methods in order to learn 17 00:01:05,580 --> 00:01:07,260 to write our code better. 18 00:01:07,280 --> 00:01:13,230 Ok so now as you can see I want to actually instantiate is all computers object. 19 00:01:13,290 --> 00:01:19,120 So here as you can see in line 52 insight is uncreate method I referred to the name of this object. 20 00:01:19,140 --> 00:01:19,970 All computers. 21 00:01:19,980 --> 00:01:22,910 Assignment operator database handler. 22 00:01:22,930 --> 00:01:27,600 You refer to the name of this object database handler that gets all computers. 23 00:01:27,600 --> 00:01:32,990 So by referring to the name of this object a database handler I can refer to the name of the Smurfit 24 00:01:33,000 --> 00:01:35,560 that I put inside this is too late handler class. 25 00:01:35,730 --> 00:01:43,020 So let's go inside this my skillet handler class as you can see I have the Smurfit here gets all computers 26 00:01:43,080 --> 00:01:47,430 objects as you can see here getting all computer objects by using this mirror that can actually get 27 00:01:47,820 --> 00:01:51,510 all the computer objects that we have inside our database. 28 00:01:51,540 --> 00:01:52,090 OK. 29 00:01:52,560 --> 00:01:57,130 So here I'll refer to the name of this Meffert and then it can actually initialize this all computerless 30 00:01:57,130 --> 00:01:57,900 the least. 31 00:01:58,070 --> 00:01:58,500 OK. 32 00:01:58,590 --> 00:02:06,900 This Arrey on here as you can see inline 50 free as you can see here computer's name assignment operator 33 00:02:07,290 --> 00:02:08,050 here. 34 00:02:08,190 --> 00:02:09,790 New at list. 35 00:02:09,900 --> 00:02:10,450 So it's going. 36 00:02:10,500 --> 00:02:15,560 So here I am just initializing these computers name on a list object as you can see here. 37 00:02:15,700 --> 00:02:21,420 This is going to be an empty Aure because we haven't actually assigned any values to this area yet. 38 00:02:21,510 --> 00:02:21,960 OK. 39 00:02:22,170 --> 00:02:26,460 So now I'm going to paste in some more lines of code here and then I'm going to explain to you what's 40 00:02:26,460 --> 00:02:27,380 going on here. 41 00:02:27,450 --> 00:02:31,960 So as you can see here these are lines of code that I actually pasted here. 42 00:02:32,070 --> 00:02:36,720 So if all computers that size is greater than zero. 43 00:02:36,970 --> 00:02:37,190 OK. 44 00:02:37,200 --> 00:02:42,200 And this means if the size of this all computers at least is greater than zero. 45 00:02:42,300 --> 00:02:43,020 OK. 46 00:02:43,230 --> 00:02:45,820 Remember that it's all computers is actually an addy. 47 00:02:45,870 --> 00:02:49,150 OK so I can I should get the size the size. 48 00:02:49,150 --> 00:02:53,620 If it is going I should return the number of elements that we have inside our list here. 49 00:02:53,640 --> 00:02:54,230 OK. 50 00:02:54,420 --> 00:03:00,600 So if all computers that size is greater than zero if this means that if we have any objects inside 51 00:03:00,690 --> 00:03:02,660 our school database OK. 52 00:03:02,670 --> 00:03:07,050 If the number of objects inside our database is greater than zero. 53 00:03:07,110 --> 00:03:07,440 OK. 54 00:03:07,440 --> 00:03:12,930 And this means that we have at least one computer object inside our database. 55 00:03:12,930 --> 00:03:13,440 OK. 56 00:03:13,710 --> 00:03:19,500 So if this condition here evaluates to true then it's going to go inside this statement and execute 57 00:03:19,500 --> 00:03:20,340 this for loop here. 58 00:03:20,340 --> 00:03:23,280 So for I created a for loop here so forth. 59 00:03:23,430 --> 00:03:28,530 And as you can see here first of all I created a variable and I assign the value zero to this variable 60 00:03:28,680 --> 00:03:29,900 which its name is I. 61 00:03:29,970 --> 00:03:30,710 OK. 62 00:03:30,840 --> 00:03:35,880 And then here I created a condition which determines how many times this rule is going to be executed. 63 00:03:35,880 --> 00:03:39,650 So I is less than all computers that size. 64 00:03:39,690 --> 00:03:45,780 So this group is going to be executed until the value of this all variable is less than the size of 65 00:03:45,800 --> 00:03:47,320 these computers list. 66 00:03:47,580 --> 00:03:49,950 And finally here I put this piece of code here. 67 00:03:49,950 --> 00:03:55,110 In order to specify that after each execution of this for loop the value of this all value is going 68 00:03:55,110 --> 00:03:57,040 to be incremented by 1. 69 00:03:57,480 --> 00:03:59,560 And inside this fall who has the answer here. 70 00:03:59,760 --> 00:04:04,990 I created an object of type computer so computer computer assignment operator. 71 00:04:05,190 --> 00:04:10,740 And then I referred to the name of these all computers list which actually holds all the computer objects 72 00:04:11,070 --> 00:04:13,120 that we have inside our database. 73 00:04:13,200 --> 00:04:19,860 So all computers that get high so it's got this gets all it's going to actually give me the specific 74 00:04:19,920 --> 00:04:26,460 object that we have inside this specific index of our array of our database as you can see here. 75 00:04:26,460 --> 00:04:31,170 So for example for the first time that this group is going to be executed the value that is assigned 76 00:04:31,170 --> 00:04:33,360 to this are is zero right. 77 00:04:33,390 --> 00:04:40,140 So all computers that get zero means the first object in sight are all computers at least. 78 00:04:40,290 --> 00:04:40,830 OK. 79 00:04:41,010 --> 00:04:43,620 And it's going to assign that value to these computed object. 80 00:04:43,710 --> 00:04:51,360 And then here in line 61 I am actually initializing these computer name at a list as you can see here 81 00:04:51,660 --> 00:04:52,880 in line 53. 82 00:04:52,890 --> 00:04:54,430 I initialized this on a list here. 83 00:04:54,450 --> 00:04:54,990 OK. 84 00:04:55,230 --> 00:05:00,050 And I specified that this at least this computer's name release is going to be anti-art that you want 85 00:05:00,050 --> 00:05:07,230 to actually add real objects to these computers name at a rate so computers name that add. 86 00:05:07,670 --> 00:05:14,170 So here I refer to the name of this object computer as you can see here that good computer name. 87 00:05:14,210 --> 00:05:19,550 So in this computer class as you can see we have these getters and setters in order to actually access 88 00:05:19,550 --> 00:05:21,950 the values of our instance variables. 89 00:05:21,950 --> 00:05:22,850 Right. 90 00:05:22,850 --> 00:05:27,510 So I can actually get the computer name plus and he had instead of double. 91 00:05:27,530 --> 00:05:31,770 I put this dash here plus computer that gets computer type. 92 00:05:31,970 --> 00:05:35,240 So we have this computer name Dasch computer type. 93 00:05:35,240 --> 00:05:35,940 OK. 94 00:05:36,530 --> 00:05:36,780 And it's. 95 00:05:36,800 --> 00:05:42,290 And this is going to be executed and iteration over all the elements inside the school like the top 96 00:05:42,320 --> 00:05:43,160 which is actually finished. 97 00:05:43,160 --> 00:05:43,690 OK. 98 00:05:43,910 --> 00:05:50,090 So remember that this Smurfette this gets all computers Meffert is going to return all the objects all 99 00:05:50,090 --> 00:05:54,940 the computer optics that we have inside our school database and it's going to be assigned us of the 100 00:05:54,950 --> 00:05:57,180 city's all computers list. 101 00:05:57,260 --> 00:05:59,320 And here we have access to that list. 102 00:05:59,390 --> 00:05:59,950 OK. 103 00:06:00,230 --> 00:06:08,120 And we can actually add singles updates to this computer object and then we can actually add those objects 104 00:06:08,120 --> 00:06:10,180 to these can computers name addy. 105 00:06:10,320 --> 00:06:16,170 OK so now let's I should I should paste in some lines of code here. 106 00:06:16,290 --> 00:06:21,330 So after this if statement here as you can see inside this uncreate Meffert again I want to pasting 107 00:06:21,330 --> 00:06:25,130 some lines of code and then I'm going explain to you what's going on here. 108 00:06:25,140 --> 00:06:29,610 So as you can see here these are the lines of code that I pasted here. 109 00:06:29,820 --> 00:06:36,330 So here are want to instantiate this adapted object that I'd declare inside our class in line 27. 110 00:06:36,330 --> 00:06:41,780 As you can see here I declare this object here at the adapter and the name of this object is adapter. 111 00:06:41,790 --> 00:06:47,880 So now I want to instantiate this adapter object so I referred to the name of this object adapter assignment 112 00:06:47,880 --> 00:06:50,560 operator new at a adapter. 113 00:06:50,730 --> 00:06:53,870 So you want to instantiate this adapter object. 114 00:06:54,060 --> 00:06:59,610 And here are this idea that there are two things against this construct and actually accepts free arguments. 115 00:06:59,610 --> 00:07:01,680 The first one is going to be the context. 116 00:07:01,680 --> 00:07:08,810 So here you could actually just put this key word here or I could just type in main activity that does 117 00:07:09,260 --> 00:07:10,140 so in this case. 118 00:07:10,140 --> 00:07:12,280 In this way we are more specific. 119 00:07:12,300 --> 00:07:12,780 OK. 120 00:07:13,080 --> 00:07:19,560 So this is the context and for the second argument we need to specify how our items inside our List 121 00:07:19,560 --> 00:07:20,790 View are going to look like. 122 00:07:20,820 --> 00:07:23,220 So I want a simple list item. 123 00:07:23,220 --> 00:07:30,250 So I just the first with the name of this android data are that lay out that simple list item one. 124 00:07:30,450 --> 00:07:30,890 OK. 125 00:07:31,080 --> 00:07:37,920 So this means that you want a simple list item 1 and I use this item for my application for my list 126 00:07:37,920 --> 00:07:43,650 view and for the first argument as you can see here we need to provide the values that we want to actually 127 00:07:43,650 --> 00:07:45,060 put in our list. 128 00:07:45,120 --> 00:07:49,980 So the values that I want to put in my list is going to be computer's name right list view. 129 00:07:50,010 --> 00:07:56,190 So this computer's name is going to be an array that can actually hold objects of type computer as you 130 00:07:56,190 --> 00:07:57,830 can see inside is for a loop. 131 00:07:57,840 --> 00:08:03,570 I am actually adding some real objects to this computer's name addy which actually holds values of type 132 00:08:03,570 --> 00:08:03,960 string. 133 00:08:03,970 --> 00:08:08,340 So as you can see I am actually assigning the values of type string to this arii. 134 00:08:08,760 --> 00:08:12,250 So here as you can see we are in here. 135 00:08:12,270 --> 00:08:16,950 I specify that you want to use these values for my list view right. 136 00:08:16,980 --> 00:08:18,590 So in line sixty eight. 137 00:08:18,700 --> 00:08:24,210 Are you referring to the name of this object list view that set adapter adapter. 138 00:08:24,270 --> 00:08:30,000 So here for that for the argument I guess I should be assigned this by the adapter here for the argument 139 00:08:30,000 --> 00:08:31,750 of this set the latter method. 140 00:08:32,100 --> 00:08:39,550 So this is going to be the adapter of this list view and it's going actually specify the lock and the 141 00:08:39,600 --> 00:08:44,340 appearance of the items that we want to put in our list view and the values that you want to put in 142 00:08:44,340 --> 00:08:45,300 my list view. 143 00:08:45,570 --> 00:08:46,230 OK. 144 00:08:46,500 --> 00:08:48,270 So hopefully that makes sense. 145 00:08:48,270 --> 00:08:54,970 And now as you can see here if you have this anklet if it here and here I created this statement. 146 00:08:54,970 --> 00:09:00,060 So when the user clicks on this BT and I hear this case statement is going to be executed and when the 147 00:09:00,060 --> 00:09:04,440 user clicks and it's written delete here this case statement is going to be executed. 148 00:09:04,590 --> 00:09:10,110 So when the user clicks on this BT an ad I want to actually add one item which is of type computer I 149 00:09:10,110 --> 00:09:13,020 want to add that item to the list view. 150 00:09:13,170 --> 00:09:18,960 OK so now I'm going to pasting some lines of code here and then I'm going to explain to you what's going 151 00:09:18,960 --> 00:09:19,560 on here. 152 00:09:19,590 --> 00:09:24,330 So as you can see here these are the lines of code that I actually pasted here. 153 00:09:24,450 --> 00:09:27,200 So now I'm going to explain to you what's going on here. 154 00:09:27,390 --> 00:09:30,300 So first of all as you can see here in line 87. 155 00:09:30,330 --> 00:09:35,240 So now remember that here we are actually inside this case statement of the speedy at. 156 00:09:35,280 --> 00:09:40,230 So when the user clicks on this bit here at these lines of code here is going to be executed. 157 00:09:40,410 --> 00:09:45,180 So in line 87 I created an object of type computer as you can see here. 158 00:09:45,180 --> 00:09:47,660 And here I am actually initializing this object so. 159 00:09:47,670 --> 00:09:49,880 Assignment operator new computer. 160 00:09:50,070 --> 00:09:55,500 And for the first argument I specified that I want to actually get the computer name. 161 00:09:55,500 --> 00:10:00,900 So as you can see here in site our activity underlined minute example if we have this it takes here. 162 00:10:00,900 --> 00:10:01,560 Right. 163 00:10:01,560 --> 00:10:06,330 So here for the first one I want to specify the computer name and for the second one I want to specify 164 00:10:06,330 --> 00:10:07,500 the computer type. 165 00:10:07,500 --> 00:10:13,760 So I want to get the values that the user entered and enters on this editor. 166 00:10:13,830 --> 00:10:20,130 And I want to actually get those values and specify the computer name on the computer name and the computer 167 00:10:20,130 --> 00:10:21,060 type. 168 00:10:21,060 --> 00:10:22,580 So let's go back to our main activity class. 169 00:10:22,570 --> 00:10:27,410 So here I want to get this ADT computer name here that takes that to strange. 170 00:10:27,480 --> 00:10:33,930 So I want to I need to actually convert that value to a string value because this a computer or constructed 171 00:10:33,930 --> 00:10:35,720 needs a string value OK. 172 00:10:35,970 --> 00:10:41,450 And for the second argument we need to specify our understand the value for the ADT computer type. 173 00:10:41,490 --> 00:10:41,960 OK. 174 00:10:42,150 --> 00:10:44,970 So ADT computer type that takes that has three. 175 00:10:45,300 --> 00:10:46,920 So this is our computer object. 176 00:10:46,950 --> 00:10:51,900 When a user clicks on it's PTEN at a computer it's is going to be it's going to be created up with these 177 00:10:51,900 --> 00:10:53,600 values and here. 178 00:10:53,790 --> 00:11:00,560 I created an if statement and here I am saying that if is the computer running that get text the truest 179 00:11:00,560 --> 00:11:08,760 thing that matches an empty string value or EDT computer type that gettext the district that matches 180 00:11:09,090 --> 00:11:11,050 an empty string value. 181 00:11:11,270 --> 00:11:17,290 It's not going to actually execute all the other lines of quote here after this statement. 182 00:11:17,300 --> 00:11:24,320 So we need to actually provide a value for our are actually for our editor texts. 183 00:11:24,440 --> 00:11:25,110 OK. 184 00:11:25,310 --> 00:11:29,850 If they use it for example doesn't provide a value for our text fields. 185 00:11:30,120 --> 00:11:35,180 These are these lines of thought here are not going to be executed so that an object is not going to 186 00:11:35,180 --> 00:11:37,730 be added to our database. 187 00:11:37,900 --> 00:11:40,060 OK so let me I actually did it. 188 00:11:40,250 --> 00:11:45,920 Let me ask you to cut this statement here and let's actually put it here before the creation of this 189 00:11:45,950 --> 00:11:53,450 object because it is better because if the user doesn't provide a value for these for these text fields 190 00:11:53,670 --> 00:11:58,450 it is not going to actually execute these lines of code here and it's not going to actually create an 191 00:11:58,520 --> 00:12:00,260 object of type of type computer. 192 00:12:00,440 --> 00:12:01,860 So it's better to put it here. 193 00:12:01,970 --> 00:12:08,720 And if they use it provides a value for these it it takes all these text fields then it's going to create 194 00:12:08,720 --> 00:12:13,240 an object of type computer and it's going to it's going to actually for the computer. 195 00:12:13,320 --> 00:12:19,790 We I to get the text of this idiotic computer name and then converted this to a string value and it's 196 00:12:19,790 --> 00:12:22,460 going actually for their computer type. 197 00:12:22,480 --> 00:12:28,440 And I try to get these idiotic computer type that get taste and then convert it a string value. 198 00:12:28,880 --> 00:12:35,420 And then here as you can see I'm going to add this computer object to our all computers list. 199 00:12:35,710 --> 00:12:36,190 OK. 200 00:12:36,410 --> 00:12:42,560 So we need to add this computer object to our computers at least and then in 1993 I am actually adding 201 00:12:42,590 --> 00:12:49,340 this computer object to our database database handler that adds computer computer. 202 00:12:49,340 --> 00:12:54,170 So if we need to add this object to our school database this is very important. 203 00:12:54,230 --> 00:12:57,010 And then in 1994 as you can see here. 204 00:12:57,050 --> 00:13:02,640 So here as you can see I am actually assigning a string value to these computer names. 205 00:13:02,700 --> 00:13:04,660 Treat these computers name at 8. 206 00:13:04,730 --> 00:13:10,220 So here I referred to that name of these computers named at a here as you can see we have this at de-listed 207 00:13:10,250 --> 00:13:12,250 as you can see in line 23. 208 00:13:12,260 --> 00:13:17,090 I actually declared this at least and its name is computerless name here. 209 00:13:17,300 --> 00:13:23,020 And this at least is going to actually accept values that are of type strange and inside this uncreate 210 00:13:23,030 --> 00:13:29,270 method here as you can see I am actually instantiating these computers name at a here. 211 00:13:29,360 --> 00:13:30,010 OK. 212 00:13:30,320 --> 00:13:35,750 And here as you can see I have this if statement and in say this if statement I created a for loop in 213 00:13:35,750 --> 00:13:40,000 order to actually get the values from the skill light as you can see here. 214 00:13:40,130 --> 00:13:45,060 And then we are actually assigning those values to string values to this computer's name. 215 00:13:45,090 --> 00:13:51,010 And if we have actually objects if we have computed objects inside our schools. 216 00:13:51,040 --> 00:13:51,350 OK. 217 00:13:51,420 --> 00:13:52,420 Inside is uncreate me. 218 00:13:52,490 --> 00:13:55,150 I actually added these lines of code here. 219 00:13:55,340 --> 00:14:01,190 But when the user clicks on these add button I want to actually add this computer object here as you 220 00:14:01,190 --> 00:14:01,800 can see. 221 00:14:01,850 --> 00:14:04,510 I want to add this computer object into the database. 222 00:14:04,640 --> 00:14:09,830 And I want to actually get us think rather you kept the computer name and the computer name. 223 00:14:09,830 --> 00:14:11,710 These are actually string values right. 224 00:14:11,710 --> 00:14:15,720 I want to get these values and assigned him to these computers named Ari. 225 00:14:15,800 --> 00:14:16,360 OK. 226 00:14:16,610 --> 00:14:21,820 So then they use it for example or clicks and this at button on a computer object is going to be created 227 00:14:22,080 --> 00:14:22,470 and. 228 00:14:22,610 --> 00:14:27,920 And the computer name and the computer type as you can see here are going to be added to the computer's 229 00:14:27,920 --> 00:14:28,930 name address here. 230 00:14:28,940 --> 00:14:36,410 So these values are going to be a string value as you can see I am actually adding these values together. 231 00:14:36,410 --> 00:14:42,210 I am actually concatenating the value of this a computer name with disvalue computer type. 232 00:14:42,320 --> 00:14:44,680 And we have a dash between these two values. 233 00:14:44,720 --> 00:14:45,470 OK. 234 00:14:45,770 --> 00:14:52,790 And here in 1995 after we added this computer object to the database and then we added this computed 235 00:14:52,790 --> 00:14:54,050 object to our three. 236 00:14:54,150 --> 00:14:56,180 At least he had as he can see. 237 00:14:56,240 --> 00:15:01,460 I want to actually set the text of our editor The Artist field to. 238 00:15:01,670 --> 00:15:08,450 Interesting value as you can see here and here I want to set the text of our computer type a computer 239 00:15:08,450 --> 00:15:12,600 type to another OTTWAY actually an empty string value OK. 240 00:15:13,010 --> 00:15:15,150 And here I fooled approach statement. 241 00:15:15,260 --> 00:15:22,460 OK so now let's me actually pasting some lines of code here for this PTEN dealing here inside the city 242 00:15:22,470 --> 00:15:27,260 in which case here I want to paste in some lines of code and then I'm gonna explain to you what's going 243 00:15:27,260 --> 00:15:27,910 on here.