0 1 00:00:04,340 --> 00:00:05,340 After learning tkinter 1 2 00:00:05,340 --> 00:00:06,810 widgets now we are ready to create 2 3 00:00:06,810 --> 00:00:08,200 our GUI applications. 3 4 00:00:08,200 --> 00:00:09,350 And in this lecture we are going 4 5 00:00:09,350 --> 00:00:11,000 to create a calculator app. 5 6 00:00:11,000 --> 00:00:12,107 What is our application? 6 7 00:00:12,107 --> 00:00:14,930 Let me show it, as you see now 7 8 00:00:14,930 --> 00:00:17,060 this is a classic calculator app. 8 9 00:00:17,060 --> 00:00:18,650 But actually its not very classic. 9 10 00:00:18,650 --> 00:00:22,534 What I mean, because here we have more features. 10 11 00:00:22,534 --> 00:00:25,100 For example we will use here a status bar, 11 12 00:00:25,100 --> 00:00:27,240 and will show our operations here. 12 13 00:00:27,240 --> 00:00:29,100 Our history here, okay? 13 14 00:00:29,100 --> 00:00:31,530 And after here, what is next? 14 15 00:00:31,530 --> 00:00:32,860 Also we have a delete button, 15 16 00:00:32,860 --> 00:00:35,070 clear button for our application 16 17 00:00:35,070 --> 00:00:37,750 and also we can, this is the most important part 17 18 00:00:37,750 --> 00:00:40,090 we can make multiple operations 18 19 00:00:40,090 --> 00:00:40,970 with this application. 19 20 00:00:40,970 --> 00:00:42,200 What I mean, for example 20 21 00:00:42,200 --> 00:00:44,870 here I can say seven plus 21 22 00:00:44,870 --> 00:00:45,720 three 22 23 00:00:45,720 --> 00:00:47,600 times six 23 24 00:00:47,600 --> 00:00:49,010 divided by nine 24 25 00:00:49,010 --> 00:00:50,439 minus six 25 26 00:00:50,439 --> 00:00:52,100 and after that, 26 27 00:00:52,100 --> 00:00:52,933 equals. 27 28 00:00:52,933 --> 00:00:53,973 As you see now it says, 28 29 00:00:57,449 --> 00:00:58,600 our output is three point zero. 29 30 00:00:58,600 --> 00:00:59,890 Its a float number by the way. 30 31 00:00:59,890 --> 00:01:01,750 And our history is here, 31 32 00:01:01,750 --> 00:01:03,610 let me make another one. 32 33 00:01:03,610 --> 00:01:06,360 Also let me show you delete button. 33 34 00:01:06,360 --> 00:01:08,663 This is delete button and as you see now, 34 35 00:01:08,663 --> 00:01:11,750 I delete my characters, also of course 35 36 00:01:11,750 --> 00:01:15,810 I can erase all of them, to press clear button 36 37 00:01:15,810 --> 00:01:18,440 and let me make another operations here. 37 38 00:01:18,440 --> 00:01:20,570 45 times 38 39 00:01:20,570 --> 00:01:22,390 three minus six 39 40 00:01:22,390 --> 00:01:25,240 okay that means 135, 40 41 00:01:25,240 --> 00:01:26,073 129 41 42 00:01:27,011 --> 00:01:29,780 and it should be 129 42 43 00:01:29,780 --> 00:01:32,880 if I press equals, as you see now 43 44 00:01:32,880 --> 00:01:36,230 129 is here and also we show it here. 44 45 00:01:36,230 --> 00:01:38,760 At our status bar, 45 46 00:01:38,760 --> 00:01:41,690 by the way our last operation is that one. 46 47 00:01:41,690 --> 00:01:43,010 This is our first operation, 47 48 00:01:43,010 --> 00:01:45,670 that means we are displaying our operations 48 49 00:01:45,670 --> 00:01:48,450 from last to first, okay? 49 50 00:01:48,450 --> 00:01:51,070 And other one I also want to show you what we can do, 50 51 00:01:51,070 --> 00:01:53,570 also we can find power of numbers 51 52 00:01:53,570 --> 00:01:55,150 to use our application. 52 53 00:01:55,150 --> 00:01:57,023 For example, four, 53 54 00:01:58,590 --> 00:01:59,490 what we need to do 54 55 00:02:00,459 --> 00:02:03,570 is press multiplication button two times okay? 55 56 00:02:03,570 --> 00:02:06,550 And the power of two, 56 57 00:02:06,550 --> 00:02:07,383 for four 57 58 00:02:07,383 --> 00:02:08,550 as you see now is 16. 58 59 00:02:08,550 --> 00:02:12,370 Of course we can find any power of numbers. 59 60 00:02:12,370 --> 00:02:17,370 For example for six, lets find the power of three. 60 61 00:02:17,490 --> 00:02:20,143 As you see now it says 216. 61 62 00:02:21,182 --> 00:02:23,880 Or lets try for something else, 62 63 00:02:23,880 --> 00:02:28,180 for example this one and power of five. 63 64 00:02:28,180 --> 00:02:30,310 As you see now, its a huge number. 64 65 00:02:30,310 --> 00:02:33,050 Anyway, so it's really a very useful application. 65 66 00:02:33,050 --> 00:02:35,920 And we will learn a lot with this application. 66 67 00:02:35,920 --> 00:02:37,930 And also we will use here an icon 67 68 00:02:37,930 --> 00:02:41,190 for our button, but it's here it's our folder 68 69 00:02:41,190 --> 00:02:43,790 I already created, Icons, the folder name 69 70 00:02:43,790 --> 00:02:47,040 and also our PNG file is here. 70 71 00:02:47,040 --> 00:02:49,570 Lets get started, what we need to do 71 72 00:02:49,570 --> 00:02:53,010 here firstly I will create another Python file. 72 73 00:02:53,010 --> 00:02:55,743 And I'll say, here, New, 73 74 00:02:57,982 --> 00:02:58,815 Python file. 74 75 00:02:58,815 --> 00:03:02,450 And here I'll say, Calculator for Python file. 75 76 00:03:02,450 --> 00:03:03,283 Okay? 76 77 00:03:03,283 --> 00:03:04,790 And here what I need to do first of all, 77 78 00:03:04,790 --> 00:03:08,920 I need to say, from tkinter import asterisk 78 79 00:03:10,100 --> 00:03:14,060 that means from tkinter import everything. 79 80 00:03:14,060 --> 00:03:17,110 And after that here, of course root is 80 81 00:03:18,240 --> 00:03:20,030 equals Tk 81 82 00:03:20,030 --> 00:03:22,010 and here lets create 82 83 00:03:22,010 --> 00:03:24,203 a title for our application. 83 84 00:03:26,953 --> 00:03:29,160 Root.title 84 85 00:03:29,160 --> 00:03:31,550 and lets say 85 86 00:03:31,550 --> 00:03:34,270 Calculator App, 86 87 00:03:34,270 --> 00:03:38,590 enough and after that we need to define geometry 87 88 00:03:38,590 --> 00:03:39,540 for our application. 88 89 00:03:39,540 --> 00:03:40,970 For geometry I will say 89 90 00:03:42,340 --> 00:03:43,400 380x 90 91 00:03:44,910 --> 00:03:46,020 550. 91 92 00:03:46,020 --> 00:03:48,243 Okay and also location of our window. 92 93 00:03:49,553 --> 00:03:53,020 For 850 plus 200 okay? 93 94 00:03:53,020 --> 00:03:53,853 And after that what I need to do, 94 95 00:03:53,853 --> 00:03:58,460 I need to say here root.mainloop right? 95 96 00:03:58,460 --> 00:04:00,240 And now if I run my application. 96 97 00:04:00,240 --> 00:04:03,050 My window is ready, as you see now 97 98 00:04:03,050 --> 00:04:04,750 our window is here, but of course 98 99 00:04:04,750 --> 00:04:06,080 its totally empty. 99 100 00:04:06,080 --> 00:04:08,060 So what we need to to first of all, 100 101 00:04:08,060 --> 00:04:10,110 we will create our buttons. 101 102 00:04:10,110 --> 00:04:12,003 And how we can create our buttons, 102 103 00:04:13,033 --> 00:04:15,720 actually before buttons we need to create our entry right? 103 104 00:04:15,720 --> 00:04:18,510 Lets create our entry here, entry box 104 105 00:04:19,376 --> 00:04:22,610 and I will come here and say here comment line 105 106 00:04:23,600 --> 00:04:26,613 and let's say Entry Box. 106 107 00:04:28,180 --> 00:04:30,410 And after that here I say 107 108 00:04:31,810 --> 00:04:32,930 entry box 108 109 00:04:35,980 --> 00:04:37,230 is equal to 109 110 00:04:38,490 --> 00:04:41,487 what I need use, first of all by the way 110 111 00:04:41,487 --> 00:04:43,957 I will only use tkinter widgets okay? 111 112 00:04:43,957 --> 00:04:46,470 That's why I didn't import ttk. 112 113 00:04:46,470 --> 00:04:48,640 And here we will say Entry and after 113 114 00:04:48,640 --> 00:04:50,930 our first property will be font 114 115 00:04:50,930 --> 00:04:53,478 and something else I want to tell you. 115 116 00:04:53,478 --> 00:04:56,760 Now here I can say root for master 116 117 00:04:56,760 --> 00:04:58,829 but I will not use root because 117 118 00:04:58,829 --> 00:05:01,665 we will not use another frame 118 119 00:05:01,665 --> 00:05:03,712 and we will have only this main window. 119 120 00:05:03,712 --> 00:05:04,970 That's why I don't use root here. 120 121 00:05:04,970 --> 00:05:09,410 And I say here font is equal to my first property. 121 122 00:05:09,410 --> 00:05:12,770 And Verdana for font family name. 122 123 00:05:12,770 --> 00:05:15,750 14 and it will be bold okay? 123 124 00:05:15,750 --> 00:05:18,500 And for the width, I'll say width 124 125 00:05:18,500 --> 00:05:20,180 is equal to 22 125 126 00:05:21,500 --> 00:05:24,660 and other one is, lets use border. 126 127 00:05:24,660 --> 00:05:26,840 For border I will say 10. 127 128 00:05:26,840 --> 00:05:28,260 Now what I need to do, 128 129 00:05:28,260 --> 00:05:30,720 I need to use a geometry manager right? 129 130 00:05:30,720 --> 00:05:33,760 I will use place geometry for my entry box. 130 131 00:05:33,760 --> 00:05:36,840 And here I will say entry box.place 131 132 00:05:38,760 --> 00:05:42,580 for place I will say x is 20 132 133 00:05:42,580 --> 00:05:45,550 and for y i'll say 10. 133 134 00:05:45,550 --> 00:05:47,810 Now, our entry box is ready. 134 135 00:05:47,810 --> 00:05:49,660 Lets run it, our application. 135 136 00:05:49,660 --> 00:05:51,610 As you see now our entry box is here, 136 137 00:05:51,610 --> 00:05:54,300 and the border looks nice right? 137 138 00:05:54,300 --> 00:05:56,980 But let me type it, 138 139 00:05:56,980 --> 00:05:57,813 you see? 139 140 00:05:57,813 --> 00:05:59,220 Also we can type it here. 140 141 00:05:59,220 --> 00:06:02,640 But the problem is here, we need to justify here 141 142 00:06:02,640 --> 00:06:05,160 because calculator apps as you know 142 143 00:06:05,160 --> 00:06:06,770 it starts from right to left 143 144 00:06:06,770 --> 00:06:08,920 and you can write from right to left. 144 145 00:06:08,920 --> 00:06:10,640 But this one is from left to right 145 146 00:06:10,640 --> 00:06:13,970 so here what I will say, I will say here... 146 147 00:06:13,970 --> 00:06:14,830 justify 147 148 00:06:16,780 --> 00:06:18,020 is equal to 148 149 00:06:19,550 --> 00:06:20,710 right, okay? 149 150 00:06:20,710 --> 00:06:24,770 And also lets use background for our entry. 150 151 00:06:24,770 --> 00:06:26,553 For background I will say here, 151 152 00:06:27,955 --> 00:06:30,150 I will use something like blue. 152 153 00:06:30,150 --> 00:06:31,660 E six 153 154 00:06:31,660 --> 00:06:32,800 e six 154 155 00:06:32,800 --> 00:06:34,620 f a okay? 155 156 00:06:34,620 --> 00:06:38,440 And after that here if I run my application. 156 157 00:06:38,440 --> 00:06:40,370 First lets run it, as you see now 157 158 00:06:40,370 --> 00:06:44,390 it's better and it justifies from right to left 158 159 00:06:44,390 --> 00:06:45,453 it's also fine. 159 160 00:06:46,850 --> 00:06:49,620 What is next, let me delete this one. 160 161 00:06:49,620 --> 00:06:53,507 Now I want to also use a default value 161 162 00:06:53,507 --> 00:06:57,950 here for my entry box, like something like that okay? 162 163 00:06:57,950 --> 00:06:58,860 So how can I do that? 163 164 00:06:58,860 --> 00:07:01,110 To do that, here I need to say 164 165 00:07:02,578 --> 00:07:05,830 entry box.insert 165 166 00:07:05,830 --> 00:07:07,380 and for the index 166 167 00:07:07,380 --> 00:07:08,760 I need to say zero 167 168 00:07:08,760 --> 00:07:10,140 and my 168 169 00:07:11,360 --> 00:07:14,350 text string will be O. 169 170 00:07:14,350 --> 00:07:16,350 I will not use zero here, why is like that? 170 171 00:07:16,350 --> 00:07:19,310 Because if I want to make, like from here 171 172 00:07:23,280 --> 00:07:25,480 if I want to use zero point five, 172 173 00:07:25,480 --> 00:07:27,790 zero point nine or these kind of numbers. 173 174 00:07:27,790 --> 00:07:32,290 I cannot use zero, so the default value will be O. 174 175 00:07:32,290 --> 00:07:34,304 It looks like a zero by the way, 175 176 00:07:34,304 --> 00:07:35,766 capital O, okay? 176 177 00:07:35,766 --> 00:07:39,247 If I run my application now, you see now its here 177 178 00:07:39,247 --> 00:07:41,414 and it looks like a zero. 178 179 00:07:41,414 --> 00:07:44,283 And what is next, now we need to create our buttons. 179 180 00:07:44,283 --> 00:07:47,550 Right here, by the way I want to tell you something. 180 181 00:07:47,550 --> 00:07:50,550 Now of course we can create our buttons manually, 181 182 00:07:50,550 --> 00:07:53,330 like we can create a button and after that copy 182 183 00:07:53,330 --> 00:07:55,010 its code and create the others. 183 184 00:07:55,010 --> 00:07:56,760 But it's not a good way. 184 185 00:07:56,760 --> 00:07:58,260 We need to use a Pythonic way. 185 186 00:07:58,260 --> 00:07:59,760 Okay to create our buttons. 186 187 00:07:59,760 --> 00:08:01,513 So what I will do, 187 188 00:08:03,432 --> 00:08:05,750 here let me say here. 188 189 00:08:05,750 --> 00:08:07,719 Number Buttons 189 190 00:08:07,719 --> 00:08:08,930 (typing) 190 191 00:08:08,930 --> 00:08:11,920 okay, this is our comment line. 191 192 00:08:11,920 --> 00:08:13,603 And after that here I will say, 192 193 00:08:15,500 --> 00:08:19,000 I can use more by the way here, okay. 193 194 00:08:19,000 --> 00:08:23,750 So for number buttons what I will say I will use here 194 195 00:08:23,750 --> 00:08:25,760 a list, okay an empty list. 195 196 00:08:25,760 --> 00:08:28,030 btn numbers 196 197 00:08:28,030 --> 00:08:30,960 and this is an empty list. 197 198 00:08:30,960 --> 00:08:32,470 And after that here I will use for loop 198 199 00:08:32,470 --> 00:08:33,400 to create my buttons. 199 200 00:08:33,400 --> 00:08:35,520 I will say for i in 200 201 00:08:35,520 --> 00:08:38,040 range 10 okay? 201 202 00:08:38,040 --> 00:08:41,690 From zero to nine that means, okay? 202 203 00:08:41,690 --> 00:08:46,060 And after that here I will say btn numbers dot append 203 204 00:08:47,190 --> 00:08:49,400 and here I need to create button right? 204 205 00:08:49,400 --> 00:08:52,790 Button constructor method and after that here 205 206 00:08:52,790 --> 00:08:55,700 my properties the first one will be width 206 207 00:08:55,700 --> 00:08:57,240 is equal to four 207 208 00:09:00,910 --> 00:09:02,110 and text must be string. 208 209 00:09:03,915 --> 00:09:06,510 But this i value is already integer. 209 210 00:09:06,510 --> 00:09:09,850 So, what I need to do I need to say str i. 210 211 00:09:09,850 --> 00:09:13,100 This is important, if you don't say str 211 212 00:09:13,100 --> 00:09:15,010 you will get an error and after that here 212 213 00:09:15,010 --> 00:09:19,370 also lets use font, font is equal to times 213 214 00:09:19,370 --> 00:09:22,810 font family name 15 and bold. 214 215 00:09:22,810 --> 00:09:25,610 Okay and also I want to use border. 215 216 00:09:25,610 --> 00:09:30,270 Border for my buttons, five and that's all. 216 217 00:09:30,270 --> 00:09:35,070 So what I need to do, here now I will create a command. 217 218 00:09:35,070 --> 00:09:36,423 Later, not now okay? 218 219 00:09:37,286 --> 00:09:40,202 And now I need to place my buttons right? 219 220 00:09:40,202 --> 00:09:44,503 What I need to do, I need to create here a variable button, 220 221 00:09:46,727 --> 00:09:49,580 actually it's an integer value 221 222 00:09:49,580 --> 00:09:52,980 btn text number will be one. 222 223 00:09:52,980 --> 00:09:55,080 Okay so why it's like that. 223 224 00:09:55,080 --> 00:09:56,260 Now you will understand why I am using 224 225 00:09:56,260 --> 00:09:59,601 btn text is equal to one, after I will use 225 226 00:09:59,601 --> 00:10:01,270 enter for loop and increase this one. 226 227 00:10:01,270 --> 00:10:03,340 It will be one two three four five 227 228 00:10:03,340 --> 00:10:06,620 because our first btn is btn zero also we have. 228 229 00:10:06,620 --> 00:10:08,880 If I want to for example, 229 230 00:10:08,880 --> 00:10:10,970 if I want to display a button here I can 230 231 00:10:10,970 --> 00:10:13,570 say btn underscore number 231 232 00:10:13,570 --> 00:10:16,370 and square brackets one two three. 232 233 00:10:16,370 --> 00:10:17,830 This is my buttons right? 233 234 00:10:17,830 --> 00:10:20,440 Here I want to start from one, 234 235 00:10:20,440 --> 00:10:23,350 that's why I said btn text is equal to one. 235 236 00:10:23,350 --> 00:10:27,030 And after that here I say for i in range 236 237 00:10:28,540 --> 00:10:30,240 zero three 237 238 00:10:30,240 --> 00:10:33,160 and now I will use nested for loop okay? 238 239 00:10:33,160 --> 00:10:36,020 For j in range 239 240 00:10:36,020 --> 00:10:38,410 and again from zero to three. 240 241 00:10:38,410 --> 00:10:39,400 Okay? 241 242 00:10:39,400 --> 00:10:41,387 Normally what I need to say here 242 243 00:10:41,387 --> 00:10:45,263 I need to say btn numbers, 243 244 00:10:46,940 --> 00:10:48,160 I said btn numbers 244 245 00:10:48,160 --> 00:10:53,160 lets say it btn numbers because we have numbers right? 245 246 00:10:53,360 --> 00:10:56,310 Btn numbers, my number will be here. 246 247 00:10:56,310 --> 00:10:58,760 I need to use btn text okay? 247 248 00:10:58,760 --> 00:11:02,440 It means my first number okay? 248 249 00:11:02,440 --> 00:11:05,391 This is btn, now let me show you something. 249 250 00:11:05,391 --> 00:11:07,899 You can say like, btn... 250 251 00:11:07,899 --> 00:11:10,780 (typing) 251 252 00:11:10,780 --> 00:11:12,110 numbers 252 253 00:11:12,110 --> 00:11:14,290 and if you type something like a three 253 254 00:11:15,735 --> 00:11:17,700 that means you will call, 254 255 00:11:17,700 --> 00:11:22,500 because this is a list, and this is an index of our btn. 255 256 00:11:22,500 --> 00:11:23,570 Okay? 256 257 00:11:23,570 --> 00:11:25,533 And after that here what I need to do, 257 258 00:11:27,070 --> 00:11:29,970 for text I said btn number text okay? 258 259 00:11:29,970 --> 00:11:32,133 And after that here I will say place. 259 260 00:11:33,010 --> 00:11:35,070 Okay for the place I will say 260 261 00:11:35,070 --> 00:11:38,850 x is equal to 25 plus 261 262 00:11:38,850 --> 00:11:40,980 i times 90 262 263 00:11:42,890 --> 00:11:45,370 and after that I will change this 263 264 00:11:45,370 --> 00:11:49,050 y is equal to 70 plus 264 265 00:11:49,050 --> 00:11:50,756 j times 265 266 00:11:50,756 --> 00:11:52,830 70 266 267 00:11:52,830 --> 00:11:54,436 okay? 267 268 00:11:54,436 --> 00:11:56,967 And now if I want to, lets run it okay? 268 269 00:11:56,967 --> 00:11:59,790 (clicking) 269 270 00:11:59,790 --> 00:12:02,520 And you see now our button is here, only one 270 271 00:12:02,520 --> 00:12:05,990 why is like that because we didn't increase our text value. 271 272 00:12:05,990 --> 00:12:08,330 Here what I need to say, btn 272 273 00:12:08,330 --> 00:12:12,210 text plus equals one okay? 273 274 00:12:12,210 --> 00:12:13,653 Now if I run it again, 274 275 00:12:15,350 --> 00:12:16,940 as you see now our buttons are here. 275 276 00:12:16,940 --> 00:12:19,637 But something wrong here, why is like that? 276 277 00:12:21,400 --> 00:12:25,216 Right they should be here, one two three four five 277 278 00:12:25,216 --> 00:12:26,436 and on till nine right? 278 279 00:12:26,436 --> 00:12:27,620 So how can I solve this problem? 279 280 00:12:27,620 --> 00:12:30,170 Here I need to change to here 280 281 00:12:30,170 --> 00:12:31,490 i and j 281 282 00:12:31,490 --> 00:12:32,800 so for I 282 283 00:12:32,800 --> 00:12:34,160 I will say j 283 284 00:12:34,160 --> 00:12:36,350 and for j I will say i. 284 285 00:12:36,350 --> 00:12:40,210 Now, and if I run it again, 285 286 00:12:40,210 --> 00:12:41,430 as you see now it's correct. 286 287 00:12:41,430 --> 00:12:45,970 It's fine and why it's like that let me explain it. 287 288 00:12:45,970 --> 00:12:48,770 Here, I want to firstly print out my j and i. 288 289 00:12:52,714 --> 00:12:53,565 and I will now 289 290 00:12:53,565 --> 00:12:55,940 show you why it's like that. 290 291 00:12:55,940 --> 00:12:59,133 Now, lets come here and run it. 291 292 00:13:00,840 --> 00:13:01,673 So, 292 293 00:13:03,980 --> 00:13:08,250 first one our text is, so it's here right? 293 294 00:13:08,250 --> 00:13:09,703 And let me run it again, 294 295 00:13:11,100 --> 00:13:14,880 so its here our j value is zero 295 296 00:13:14,880 --> 00:13:16,230 and x value is zero 296 297 00:13:16,230 --> 00:13:19,390 that means btn one its location 297 298 00:13:19,390 --> 00:13:21,390 will be 25 for x 298 299 00:13:21,390 --> 00:13:24,420 because j is zero, it's here. 299 300 00:13:24,420 --> 00:13:28,450 And for y value it will be 25 and 70 okay? 300 301 00:13:28,450 --> 00:13:32,260 For this one, for second one it will be here right? 301 302 00:13:32,260 --> 00:13:36,550 The second button is here for j and i value is here. 302 303 00:13:36,550 --> 00:13:39,650 For j value it will be 25 303 304 00:13:39,650 --> 00:13:41,844 plus j is already one, 304 305 00:13:41,844 --> 00:13:44,210 times 90 that means 305 306 00:13:44,210 --> 00:13:46,710 115 right? 306 307 00:13:46,710 --> 00:13:49,530 so its here, x location okay? 307 308 00:13:49,530 --> 00:13:53,440 And for y location you see i is zero, 308 309 00:13:53,440 --> 00:13:56,700 so it will again be 70 and so on okay? 309 310 00:13:56,700 --> 00:14:00,000 So we will place our buttons 310 311 00:14:00,000 --> 00:14:03,200 to use i and j value like this okay? 311 312 00:14:03,200 --> 00:14:04,610 this is our formula 312 313 00:14:04,610 --> 00:14:07,530 And after that what I need to do here, 313 314 00:14:07,530 --> 00:14:10,239 now I already create my numbers now. 314 315 00:14:10,239 --> 00:14:13,023 I need to also use here, 315 316 00:14:14,190 --> 00:14:15,080 command right 316 317 00:14:15,080 --> 00:14:17,140 for my buttons. 317 318 00:14:17,140 --> 00:14:21,980 So I will say command, and I will use lamda. 318 319 00:14:21,980 --> 00:14:23,770 For lamda what I need to do, 319 320 00:14:23,770 --> 00:14:27,223 I want to show you something else here, let me, 320 321 00:14:29,400 --> 00:14:30,870 take it here somewhere. 321 322 00:14:30,870 --> 00:14:35,560 For lamda you say x is equal to i okay? 322 323 00:14:35,560 --> 00:14:39,050 And colon after here I will say enter 323 324 00:14:41,050 --> 00:14:42,093 here number. 324 325 00:14:43,470 --> 00:14:46,360 And here I need to pass in a parameter x. 325 326 00:14:46,360 --> 00:14:47,360 Why is like that? 326 327 00:14:47,360 --> 00:14:51,340 Now here, by the way command is equal to... 327 328 00:14:53,420 --> 00:14:54,610 Now I use " i " right? 328 329 00:14:54,610 --> 00:14:58,360 I say x is equal to "i" okay? 329 330 00:14:58,360 --> 00:15:00,410 And my function is enter number 330 331 00:15:00,410 --> 00:15:03,210 and my parameter number will be x why x? 331 332 00:15:03,210 --> 00:15:06,990 because I need to know which button was pressed okay? 332 333 00:15:06,990 --> 00:15:09,870 So this parameter will show me which button was pressed. 333 334 00:15:09,870 --> 00:15:12,379 For example here, we have nine buttons. 334 335 00:15:12,379 --> 00:15:15,200 If you press nine that x value 335 336 00:15:15,200 --> 00:15:17,480 will understand you have pressed nine, okay? 336 337 00:15:17,480 --> 00:15:19,370 That's why I need to use it like that. 337 338 00:15:19,370 --> 00:15:22,140 And here what I need to do, I will come here 338 339 00:15:22,140 --> 00:15:26,283 and create my function, here I will say. 339 340 00:15:30,090 --> 00:15:33,640 Functions, okay? 340 341 00:15:33,640 --> 00:15:38,640 and our first function will be def enter number. 341 342 00:15:38,930 --> 00:15:42,720 and here I will say enter number and x okay? 342 343 00:15:44,535 --> 00:15:47,031 And now what I need to do, 343 344 00:15:47,031 --> 00:15:49,458 we need to do here something else 344 345 00:15:49,458 --> 00:15:51,738 and let me say pass firstly 345 346 00:15:51,738 --> 00:15:52,720 (clicks) 346 347 00:15:52,720 --> 00:15:56,800 our default value is zero, actually its O 347 348 00:15:56,800 --> 00:15:58,707 but I call it zero okay? 348 349 00:15:58,707 --> 00:16:01,353 I need to remove this value okay? 349 350 00:16:02,720 --> 00:16:04,050 firstly, I will say 350 351 00:16:06,269 --> 00:16:08,410 if entry box.get 351 352 00:16:08,410 --> 00:16:11,300 okay this is our entry box value, 352 353 00:16:11,300 --> 00:16:14,200 is equals equals 353 354 00:16:15,320 --> 00:16:17,780 zero okay, and here what I need to do. 354 355 00:16:17,780 --> 00:16:21,030 I need to say entry box.delete, 355 356 00:16:21,030 --> 00:16:21,900 delete this value 356 357 00:16:23,782 --> 00:16:26,370 and first is zero 357 358 00:16:26,370 --> 00:16:28,300 from zero to end okay? 358 359 00:16:28,300 --> 00:16:29,970 And I will say here end. 359 360 00:16:29,970 --> 00:16:31,780 And after here what I need to do 360 361 00:16:32,711 --> 00:16:34,430 I need to say entry box.insert 361 362 00:16:35,777 --> 00:16:37,830 and my button value 362 363 00:16:37,830 --> 00:16:40,750 str x okay? 363 364 00:16:40,750 --> 00:16:42,573 Now if I run my application, 364 365 00:16:44,090 --> 00:16:46,920 if I look it's here now it's zero. 365 366 00:16:46,920 --> 00:16:49,330 If I press two, as you see now 366 367 00:16:49,330 --> 00:16:50,340 two is here. 367 368 00:16:50,340 --> 00:16:52,520 But if I press three, you see? 368 369 00:16:52,520 --> 00:16:55,430 It doesn't affect anything, nothing happens 369 370 00:16:55,430 --> 00:16:57,371 why is like that? 370 371 00:16:57,371 --> 00:16:59,400 Because here we need to use indexes, okay? 371 372 00:16:59,400 --> 00:17:03,430 First index is already taken by this two, okay? 372 373 00:17:03,430 --> 00:17:05,923 And here what I need to do is use else, 373 374 00:17:05,923 --> 00:17:09,557 and I will say, else length 374 375 00:17:09,557 --> 00:17:12,660 I will say length too for indices 375 376 00:17:12,660 --> 00:17:14,290 length is equal to len 376 377 00:17:15,218 --> 00:17:19,610 of my entry box.get value okay? 377 378 00:17:19,610 --> 00:17:21,540 And here I will say after that, 378 379 00:17:21,540 --> 00:17:23,870 entry box.insert 379 380 00:17:23,870 --> 00:17:25,520 this time, 380 381 00:17:25,520 --> 00:17:26,353 length 381 382 00:17:27,870 --> 00:17:31,180 and here str x. 382 383 00:17:31,180 --> 00:17:34,310 Okay for second one I need to use index number okay? 383 384 00:17:34,310 --> 00:17:35,890 This is the first one okay, 384 385 00:17:35,890 --> 00:17:38,130 for second index I need to use one here. 385 386 00:17:38,130 --> 00:17:40,080 And after two and that means 386 387 00:17:41,947 --> 00:17:43,993 it depends on my length okay? 387 388 00:17:47,057 --> 00:17:49,390 Length of my entry box value okay? 388 389 00:17:49,390 --> 00:17:52,340 Or length anyway, this is the short name of it. 389 390 00:17:52,340 --> 00:17:54,693 So if I run it again, 390 391 00:17:55,680 --> 00:17:57,557 now say I press one. 391 392 00:17:57,557 --> 00:18:01,950 One is fine, two it's working, three four five 392 393 00:18:01,950 --> 00:18:05,950 six seven eight nine, all of them is working. 393 394 00:18:05,950 --> 00:18:07,130 And in this lecture we have learnt 394 395 00:18:07,130 --> 00:18:08,860 how we can create these number buttons. 395 396 00:18:08,860 --> 00:18:10,723 And also we have create our window 396 397 00:18:13,360 --> 00:18:17,440 and in next lesson we will create other functions 397 398 00:18:17,440 --> 00:18:19,780 and of course also other buttons. 398 399 00:18:19,780 --> 00:18:21,793 For now that's all, see you in the next.