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Watch everyone now in this tutorial we're going to actually go ahead and continue building our fourth



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Android application.



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So as you can see here here we actually see some errors.



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Ok the Android studio is complaining.



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And we need to actually first fix these errors in order to actually run our application.



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So let's actually fix this our first error here.



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As you can see here let's actually hover our mouse pointer over this error area and see what's the error.



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As you can see here it says there is no default constructor available income.



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That example that maters I saw that that app for that animal.



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OK.



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It refers to this animal class here.



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OK.



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So it says that there is no default constructor here and it's right because we actually created a custom



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constructor in this class as you can see here this is Arkan's custom constructor.



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OK.



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So then we actually create a constructor in our class.



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The compiler doesn't provide a default constructor for us.



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OK.



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So when you actually create a cost a constructor in the Animal class need to actually implicitly or



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explicitly call the constructor of the superclass.



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OK so now we are inside the scope of this animal class here.



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OK.



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And this animal class extends from the Object class.



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And this means that this animal class inherits all of the features and behaviors that are inside of



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this object class into this Animal class.



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OK.



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So this class inherits all of that features that are inside this object class.



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OK.



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So out the inside the object class which is a predefined class in Java.



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We've got our constructor.



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So let's actually go inside the object class and see and find that constructor OK.



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So I need to actually hold the command key and then click on this object here.



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And if you are using a Windows machine you need to actually hold the control key and then click on the



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object.



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OK.



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So as you can see here this is the constructor inside this object class.



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OK.



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And this comment says constructs a new instance of Object.



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OK.



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So as you can see here this is the constructor and this constructor doesn't actually accept any arguments.



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And as you can see here there is no implementation inside this constructor OK.



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So let's go back inside the Animal class as you can see here.



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Here we need to actually implicitly or explicitly call the constructor of the superclass because you



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are actually inheriting all of the features of this object class into the Animal class.



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The compiler does provide a default constructor for us.



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OK.



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The default constructor that is inside of this object class.



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Remember that a default constructor is a constructor without no parameters.



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OK.



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And the constructor that is inside this object class has no promotors.



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OK.



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So inside this Animal class because we are inheriting all of the features of this object class into



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this Animal class the compiler does provide a default constructor for us.



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OK so we don't need to actually explicitly initialize initialize the constructor of the superclass.



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OK so the superclass is object.



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OK.



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And inside the Animal class we don't need to explicitly initialize that constructor that is inside this



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object class.



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OK the compiler does provide a default constructor for us but inside this cat class as you can see here



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there is another story here.



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Here in this class in the scope of this class we are actually extending all of the features that are



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inside of this animal class into this chat class.



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OK.



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We are inheriting all of the features and behaviors that are declared as public entities Kathe class.



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OK.



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So inside this Animal class let's actually hold the command key and then click on animal here.



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As you can see this is an Animal class.



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OK.



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Inside this class I have a custom constructor here.



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I created my own constructor for this animal class.



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So inside this chat class we need to actually initialize the constructed of the superclass So the constructor



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of the superclass is this constructor OK.



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So inside the constructor of this Chadha class we need to initialize the constructor of the superclass



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otherwise the compiler is going to actually complain and we would not be able to run our application.



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So in order to initialize the constructor of the superclass which is this animal class I just need to



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type in here super.



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OK.



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And then inside the apprentice's as you can see here.



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I need to actually passing some values.



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OK.



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Let's actually hover our mouse pointer over this error area and see what's the error.



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It asks us to actually passing some values for the next instance variable and a value for.



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For the color instance variable of value for the amount of spit instance variable and of value for the



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amount of power or instance variable.



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Ok you may wonder that Verity's or instance variables come from.



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We don't have these instance variables in this chat class.



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So why do this construct and asks us to actually Pessin our values for these instance variables.



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Because you are actually inheriting all of the features of this animal class into this math class Vini



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to actually initialize those instance variables too.



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So inside this animal class as you can see here we've got this instance variables here.



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OK.



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In say the cat class we are actually inheriting all of these instance variables and methods.



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OK.



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But as you can see here these instance variables are declared as private.



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OK this instance variable is honestly part of the child's class instance variables are not visible to



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this class.



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Ok to this chat class because.



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Because this instance variables are declared as private.



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OK.



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So we need to actually pass some values to this superclass constructor in order to actually fix these



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errors.



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OK.



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So how can we actually initialize those instance variables in this class class.



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We need to actually provide some arguments inside the prentices of the constructor of this Kathe class.



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Ok so here.



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Now I want to actually provide some arguments and then I want to actually assign those arguments to



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the instance variables of the superclass which is the animal class.



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OK.



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First of all I need to provide a value for this strange named instance variable here.



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OK.



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Of types thrain in order to actually initialize the named instance variable OK.



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So the cat class.



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First of all I need to actually specify the data type of my argument.



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Strange.



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OK.



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And the name of my argument is name.



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Now I need to actually provide another argument for the coloring instance variable as you can see this



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is our color instance variable.



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So as you can see here we've got this color instance variable but this is an argument for this color



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instance variable.



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So inside the cat class and inside the Prentice's of this constructor I need to actually provide an



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argument for the color instance variable Strunk color comma and then I need to actually provide an other



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argument for this amount of speed here.



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Amount of speed instance variable here.



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OK.



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So inside the Kathe class I need to actually create another argument in amount of speed.



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OK.



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Come on.



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And then I need to actually provide another argument for this amount of power instance variable.



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OK.



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As you can see we've got this amount of power argument here and here we are actually assigning this



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argument to this instance variable here.



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OK.



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So in say the cat class you need to actually create another argument in amount of power.



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OK comma so now inside the Prentice's of this super here I can actually pass these arguments here.



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OK so name comma color comma amount of speed comma amount of power.



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OK.



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So as you can see here now the error is gone.



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OK.



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We don't see any error here.



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OK.



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Because we actually successfully initialized the constructor of the superclass.



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OK.



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So as you can see here inside the Animal class this is the constructor of the superclass and this constructor



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actually exits for arguments.



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OK.



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And inside the cat class you are actually passing D's of value for those four arguments here.



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OK of value for the name instance valuable value for the color instance variable of value for the amount



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of instance variable and a value for the amount of power instance variable.



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So here we are actually explicitly calling the constructor of the superclass.



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OK.