1

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OK as you can see here these are the components inside the screen.



2

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OK.



3

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So hopefully that makes sense.



4

00:00:07,350 --> 00:00:13,100

Let's actually double click on this content underline that example and just select the spots in here.



5

00:00:13,110 --> 00:00:15,040

So just select is a button here.



6

00:00:15,210 --> 00:00:21,010

And now let's actually find the layout here and we can try to change this value.



7

00:00:21,010 --> 00:00:24,450

This Arap content value to match palette.



8

00:00:24,720 --> 00:00:25,290

OK.



9

00:00:25,440 --> 00:00:31,840

Now as you can see here David of disputant actually covers the entire screen.



10

00:00:31,860 --> 00:00:34,300

OK the entire width of the screen.



11

00:00:34,530 --> 00:00:34,990

OK.



12

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But the wrap content attribute actually wraps this button around its contents.



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00:00:40,800 --> 00:00:41,420

OK.



14

00:00:42,250 --> 00:00:45,550

Laps the width of this button around its content.



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00:00:45,550 --> 00:00:50,190

So let's actually change this value to match parent.



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So hopefully that makes sense.



17

00:00:51,820 --> 00:00:57,600

Let's actually go inside this main activity that Java here and here we can actually put our own codes



18

00:00:57,610 --> 00:00:58,240

here.



19

00:00:58,630 --> 00:01:02,830

So as you can see here we need to actually free different classes here.



20

00:01:03,040 --> 00:01:08,860

A class called vehicle or class called car and a class called motorcycle OK.



21

00:01:09,040 --> 00:01:12,800

So let's actually create these free classes.



22

00:01:12,850 --> 00:01:13,420

OK.



23

00:01:13,480 --> 00:01:17,270

Now we want to actually create free different classes.



24

00:01:17,650 --> 00:01:23,300

So let's actually click on View tool windows and then click on Project.



25

00:01:23,310 --> 00:01:30,660

So here just click on this package here as you can see and then click on File New and then click on



26

00:01:30,840 --> 00:01:31,790

Java class.



27

00:01:31,800 --> 00:01:32,550

OK.



28

00:01:32,970 --> 00:01:38,410

So for the name of the class just type in here vehicle K..



29

00:01:38,510 --> 00:01:42,590

And now let's actually create another class called card.



30

00:01:42,650 --> 00:01:47,260

So just click on this package here find new jobs class.



31

00:01:47,320 --> 00:01:47,850

OK.



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00:01:47,890 --> 00:01:55,970

Car as you can see here are car class is created again we need to actually create another class called



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00:01:56,190 --> 00:01:57,330

motor cycle.



34

00:01:57,620 --> 00:01:59,550

So just click on this package here.



35

00:01:59,810 --> 00:02:01,550

File New.



36

00:02:01,730 --> 00:02:06,180

And then click on Jobar class motor cycle.



37

00:02:06,720 --> 00:02:07,750

OK.



38

00:02:08,210 --> 00:02:09,900

So this is our motorcycle class.



39

00:02:09,920 --> 00:02:10,660

OK.



40

00:02:11,360 --> 00:02:14,600

So let's actually work on this vehicle class here.



41

00:02:14,600 --> 00:02:20,660

This class is going to be the superior class for these two classes for this motorcycle class and for



42

00:02:20,660 --> 00:02:29,120

the car class as you know the car is actually a vehicle and a motorcycle is actually again a vehicle.



43

00:02:29,120 --> 00:02:29,680

OK.



44

00:02:29,900 --> 00:02:32,150

So let's first work on this.



45

00:02:32,280 --> 00:02:39,640

Plus here first of all I want to actually put in some instance variables that are related to this vehicle



46

00:02:39,640 --> 00:02:40,630

class.



47

00:02:41,110 --> 00:02:41,650

OK.



48

00:02:41,740 --> 00:02:47,520

Now we need to actually specify the instance variables that are related to these very vehicle class.



49

00:02:47,530 --> 00:02:48,040

OK.



50

00:02:48,100 --> 00:02:51,910

So the first instance variable is going to be the speed.



51

00:02:51,940 --> 00:02:52,690

OK.



52

00:02:52,930 --> 00:03:01,210

So first we need to actually specify the access modifier of this instance variable private's and the



53

00:03:01,210 --> 00:03:07,460

data type of this instance variable is eans and the name of this instance variable is speed.



54

00:03:07,690 --> 00:03:08,990

OK.



55

00:03:09,700 --> 00:03:13,570

Private and all vehicles have a braking system.



56

00:03:13,660 --> 00:03:14,040

OK.



57

00:03:14,080 --> 00:03:18,850

So I can just create a boolean variable has braking



58

00:03:23,580 --> 00:03:30,990

and because we are sure that all vehicles have a braking system we can actually make this variable a



59

00:03:30,990 --> 00:03:31,670

constant.



60

00:03:31,680 --> 00:03:36,840

OK so private fine on Boullion has braking system.



61

00:03:36,990 --> 00:03:39,090

All vehicles have vehicles.



62

00:03:39,270 --> 00:03:39,780

OK.



63

00:03:39,900 --> 00:03:49,590

So private int and the name of this instance variable is the number of vehicles.



64

00:03:49,590 --> 00:03:56,020

OK so now let's actually create a constructor for this vehicle class.



65

00:03:56,040 --> 00:04:02,850

So first of all I need to actually specify the access modifier of the constructor and the name of this



66

00:04:02,850 --> 00:04:07,450

constructor must be the same as the name of this class vehicle.



67

00:04:07,960 --> 00:04:08,780

OK.



68

00:04:09,090 --> 00:04:14,580

And then I need to actually put in a pair of round brackets after my constructor name and then I need



69

00:04:14,580 --> 00:04:19,000

to open and close my constructed by using these curly braces.



70

00:04:19,350 --> 00:04:25,890

So inside these Apprentice's I can actually specify some arguments the data type of the first argument



71

00:04:25,890 --> 00:04:34,350

is int and the name of this argument is speed comma and the data type of the second argument is boolean



72

00:04:35,190 --> 00:04:43,890

and the name of this argument is has braking system comma and the name of this first instance variable



73

00:04:43,890 --> 00:04:47,950

is number of years and it is of type int.



74

00:04:47,970 --> 00:04:53,640

So first I need to actually specify the data type of this argument and the name of this argument is



75

00:04:53,970 --> 00:04:54,860

number of years.



76

00:04:54,870 --> 00:04:55,360

OK.



77

00:04:55,560 --> 00:05:03,450

So inside this constructor First we need to actually specify that the constructor of the superclass



78

00:05:03,450 --> 00:05:04,600

is initialized.



79

00:05:04,890 --> 00:05:11,790

So as you know this vehicle class is implicitly inheriting all of the features and behaviors that are



80

00:05:11,970 --> 00:05:20,020

inside the object class and because inside the object class you have actually a default constructor



81

00:05:20,040 --> 00:05:23,390

we have a constructor without no parameters.



82

00:05:23,440 --> 00:05:29,450

The compiler is going to actually implicitly initialize that constructor for us.



83

00:05:29,490 --> 00:05:34,290

OK we can explicitly initialized as constructed by just typing here super.



84

00:05:34,490 --> 00:05:38,700

OK but if you don't put this a line of code here.



85

00:05:38,790 --> 00:05:43,870

The compiler is going to actually initialize the constructor of the superclass automatically for us.



86

00:05:43,910 --> 00:05:49,920

OK so we don't need to actually initialize that constructor only to actually initialize my own instance



87

00:05:49,920 --> 00:05:53,050

variables inside this constructor.



88

00:05:53,250 --> 00:06:00,480

So this does speed assignment operator speed.



89

00:06:00,780 --> 00:06:14,070

Semicolon this that has braking system assignment operator has Brahim system and this dot number of



90

00:06:14,070 --> 00:06:18,160

Veals assignments operator number of wheels.



91

00:06:18,200 --> 00:06:20,000

OK so hopefully that makes sense.



92

00:06:20,020 --> 00:06:25,510

And now let's actually create setters and getters for these instance variables.



93

00:06:25,530 --> 00:06:32,070

So inside this vehicle class and outside of these constructed just right click here and then click on



94

00:06:32,070 --> 00:06:40,140

generate and then we can get her and set her Sahir select all of these instance variables and then click



95

00:06:40,140 --> 00:06:44,910

on OK these getters and setters are actually created automatically for us.



96

00:06:44,910 --> 00:06:46,470

Get speed set speed.



97

00:06:46,470 --> 00:06:51,520

Is has braking system get number of visas and set number of wheels.



98

00:06:51,570 --> 00:06:57,730

So let's actually delete this is here and just put in the word get here.



99

00:06:57,870 --> 00:07:05,550

Get has braking system and then let's actually create an instance Smurfette for this vehicle class so



100

00:07:05,550 --> 00:07:09,150

we can actually create a method called right.



101

00:07:09,190 --> 00:07:11,530

OK Puplick void.



102

00:07:12,100 --> 00:07:14,410

Right OK.



103

00:07:15,090 --> 00:07:20,700

And then I put in a pair of round brackets after my Meffert name and then I open and close the Smurfette



104

00:07:20,960 --> 00:07:23,010

by using these curly braces.



105

00:07:23,040 --> 00:07:26,340

So here we can actually put in our own quotes.



106

00:07:26,430 --> 00:07:35,250

OK so make sure that inside of your own class to choose the getters and setters in order to access the



107

00:07:35,250 --> 00:07:37,000

value of this instance variables.



108

00:07:37,020 --> 00:07:42,070

OK in this way your quotes are going to be more maintainable and it is more secure.



109

00:07:42,330 --> 00:07:46,590

So now I want to actually produce an integer value.



110

00:07:46,770 --> 00:07:49,690

So end result.



111

00:07:50,070 --> 00:07:51,790

Assignment operator.



112

00:07:52,020 --> 00:08:02,960

And then I can actually multiply the value of this speed instance variable by the value of this number



113

00:08:02,960 --> 00:08:12,450

of violists OK so I can't just refer to the good term if it gets speed multiplied by jets number of



114

00:08:12,450 --> 00:08:12,780

wheels.



115

00:08:12,790 --> 00:08:19,800

OK so in this way you are actually referring to these guitars in order to access the value of this instance



116

00:08:19,800 --> 00:08:20,370

variables.



117

00:08:20,370 --> 00:08:21,640

OK this is a better way.



118

00:08:21,660 --> 00:08:29,810

In order to actually this the value of your instance variables always use getters or stars in order



119

00:08:29,810 --> 00:08:33,290

to manipulate the value of these instance variables.



120

00:08:33,300 --> 00:08:34,050

OK.



121

00:08:34,280 --> 00:08:39,910

And now I can actually create another instance variable here.



122

00:08:40,100 --> 00:08:47,690

For example private int and the name of this instance variable is the right speed.



123

00:08:48,040 --> 00:08:48,720

OK.



124

00:08:48,950 --> 00:08:52,550

And then I put in an assignment operator here.



125

00:08:52,640 --> 00:08:54,770

I actually put in a semicolon here.



126

00:08:54,770 --> 00:08:55,310

OK.



127

00:08:55,430 --> 00:09:03,110

So as you can see here now we can actually assign the value of this result local variable.



128

00:09:03,110 --> 00:09:09,950

So remember this result variable is actually a local variable because it is local to this method only



129

00:09:09,960 --> 00:09:10,440

OK.



130

00:09:10,520 --> 00:09:13,990

We cannot refer to this method from anywhere inside this class.



131

00:09:14,030 --> 00:09:14,640

OK.



132

00:09:14,780 --> 00:09:18,230

We can actually refer to this variable only inside this method.



133

00:09:18,380 --> 00:09:25,280

So now I can actually refer to the name of the write speed instance variable assignment operator result.



134

00:09:25,460 --> 00:09:27,460

So hopefully that makes sense.



135

00:09:27,500 --> 00:09:34,370

Let's actually only create a I'll get my head for this right speed instance variable just right here



136

00:09:34,520 --> 00:09:41,600

inside this vehicle class and then they can generate getter OK.



137

00:09:41,720 --> 00:09:44,660

I just want to create a getter for this right.



138

00:09:44,660 --> 00:09:46,580

Speed instance variable.



139

00:09:46,580 --> 00:09:47,120

OK.



140

00:09:47,300 --> 00:09:48,900

And then click on OK.



141

00:09:49,370 --> 00:09:55,430

So as you can see here now we have a getter method for this right speed instance variable.



142

00:09:55,520 --> 00:10:00,460

We can actually access the value of this right speed instance variable by using this method.



143

00:10:00,470 --> 00:10:01,030

OK.



144

00:10:01,150 --> 00:10:02,260

Get right speed.



145

00:10:02,270 --> 00:10:03,750

So hopefully that makes sense.