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Hire everyone in this theater early on I'm going to talk about inheritance in Java.



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So first of all let me point out that inheritance is one of the features of object oriented programming.



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Inheritance allows a class to use the properties and methods of another class.



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OK.



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In other words that the right class inherits this Tait's and behaviors from the base class.



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So for example we have two classes in our project and we can actually specify the base class and the



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D-Rays class and the deprived class can inherit the states and behaviors from the base class which I'll



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talk more about later.



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OK.



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That 0 2 class is also called subclass and the base class is also known as superclass.



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OK.



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So the desired class can add its own additional variables and Misfit's is additional valuable and Milford's



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differentiates the derived class from the base class.



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OK a simple class can have any number of subclasses but a subclass can have only one superclass.



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OK so this is because Java does not support multiple inheritance.



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OK this superclass and subclass have is a relationship between them.



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So now like let me actually show you a real example OK.



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OK so now let's actually consider a superclass called a shape.



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OK.



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Different shapes have different features and properties.



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However are few of them are common to all.



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For example the color of the shape the size of the shape or other properties.



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OK.



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Hence as a result we can create a class called Shape with states and actions that are common to all



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shapes.



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OK.



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So as you can see here we've got two dimensional shapes and for dimensional shapes.



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OK.



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The circle shape is a subclass of the two dimensional shape.



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The square shape is the subclass of two dimensional shape.



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And this triangle shape is a subclass of these two diminished two dimensional shape.



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Class OK.



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And on the other hand we've got three dimensional shapes.



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The sphere class is the subclass of three dimensional shape.



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The Cube class is a subclass of freedom and Shannons shape.



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And the pyramid class is the subclass of freedom engine shape.



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OK.



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As you can see here this two dimensional shape class inherits all the features and behaviors of this



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Shape class and this class can have its own behaviors or methods.



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OK these two dimensional shape class and down the hierarchy.



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This circle class inherits all the features and behaviors of these two dimensional shape class and this



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class.



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This circle class can have its own merits and features specific to the Circle class Square class.



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Again it inherits all the features and behaviors of the two dimensional shape class and it can have



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its own features and behaviors specific to this square class.



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Again the triangular class inherits all the features and behaviors of the two dimensional shape class.



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But it can have its own features and behaviors specific to this triangular class.



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And again this Fredy mention on Shape class inherits all the features and behaviors of the Shape class



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but it can have its own features and behaviors specific to that freedom in general shape glass and down



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the hierarchy as you can see this sphere class inherits all the features and behaviors of the three



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dimensional shape class.



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But it can have its own features and behaviors specific to the US sphere class and this new class inherits



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all the features and behaviors of the three dimensional shape class but it can have its own features



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and behaviors specific to this cube class.



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And it's the same story for this pyramid class.



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OK.



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But for example this triangular class cannot inherit the features or behaviors of these three dimensional



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shape class because it doesn't inherit features or behaviors of this class.



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OK.



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The triangle class can only inherit the features or behaviors of the two dimensional shape class or



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it can inherit the features or behaviors of the Shape class.



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OK.



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So here as you can see the two dimensional shape class is a shape.



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OK.



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And this circle class is a two dimensional shape.



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This square class is a two dimensional shape and this triangle class is actually a two dimensional shape.



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So as a result.



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So as you can see there is a relationship between these classes that inherit from each other.



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And again it's the same story for this freedom in a class.



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So is freedom freedom and you know Shape class is a shape.



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OK.



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There is a relationship between these two classes because this freedom mention on the Shape class actually



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inherits behaviors or features of the Shape class.



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OK.



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And this sphere class actually is a three dimensional shape because it inherits the behaviors or features



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of this freedom emotional shape class.



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And we've got this our class actually this queue class is our freedom engine and shape and as a result



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it is a shape.



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OK.



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Because this cube class actually inherits that behaviors or features of these three dimensional shape



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class and Frady mention or Shape class inherits the behaviors and features of the Shape class.



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So as a result the cube class is a shape.



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OK.



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And we've got this pyramid class this PM class is actually a free dimensional shape and as a result



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it is a shape.



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OK.



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As you can see that is it is a relationship between these classes here.



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OK.



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So hopefully that makes sense.



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So now let me actually show you another example.



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So as you can see here we've got this Animal class here and this animal class is the base class.



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OK.



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So this chat class actually inherits all the features and behaviors of this Animal class.



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OK.



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So as a result this tath class is an animal.



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OK.



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And we've got this leopard class this leopard class actually inherits all the behaviors and features



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of this cat class and this cat class inherits all the all the features and behaviors of this Animal



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class.



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So as a result this leper's class is a cat and it is also an animal.



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OK.



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Because this leopard class inherits all the features of this cat class.



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And so as a result it is a cat and it is also an animal.



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So hopefully that makes sense.



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So now let's actually go inside the anthrax and create are actually our fourth Android application.



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OK.



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Now let's actually open the Android studio and then click on start a new Android studio project.



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And then we need to actually specify a name for an application name.



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So just type in here before.



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And then here we need to actually specify a name for an application name app for and here specifically



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the company domain.



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And here you can specify the package name by clicking on the edit here and then you can actually specify



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the project location here.



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OK.



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And then click on next.



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So here make sure that you choose the API 16 Android what wanted it been for your minimum and then click



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on next.



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And here choose the blank activity and then click next.



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And here this is the this is the activity name main activity you can you can change this name if you



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want.



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This is our lay out name as you can see activity underline main.



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And this is the title main activity for our application.



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As you can see and this is the manual resource name.



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So I recommend that you don't change these names here and then click on finish.



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So as you can see here it can actually create our Android application for us.



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So first it's going to actually configure and set up the application.



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OK.



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Now as you can see our Android project is created.



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So as you can see here it's now showing us that error again.



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So we need to click on these cradle squits here and then click on this build that cradle here and then



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change change this number to number one and change this number change this number to number one.



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OK.



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So click on this scene now here and then let's go back inside.



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Inside the content underline mean that excitement as you can see now the error is gone.



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OK.



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So let's go inside the main activity that job right here.



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And as you can see let's actually delete these lines of code here.



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I'll talk more about these options.



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But for now I don't want to actually create many options in our application and here really these floating



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action Potten here.



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So let's actually go back inside the press folder here.



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And then double click on this layout folder here and then double click on this activity underline mean



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that Semmel OK.



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So click on this text tab here and then delete these lines of code here which is related to the float



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float in action button here.



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OK.



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OK.



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Now let's actually close this window here.



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This activity underline made that example.



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So just click on this X here.



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As you can see.



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So as you can see this is our main active main activity that job here.