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Higher level as you may already know our application actually has it but so what is this bug.



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Let's actually look at this smartphone computer.



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You can see that the name of this smartphone computer is actually the iPad.



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Right.



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So let's go back to android studio.



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That makes you double click on the main activity that Java tap in order to make this area wider.



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So Enceladus main activity class and inside these uncreate Smurfette you can see that when we created



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this object of type smartphone computer.



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So here let me tell you that here we are creating a variable of type smartphone computer right.



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So this is the data type and this is the name of Aradia But after this assignment operator you can see



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that you're saying new smartphone computers so here we are actually creating the actual object of type



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actually that smart computer.



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And we are assigning the actual object of type Smarthome computer to this valuable type smartphone computer



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and the name of this variable is a smartphone computer.



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So look at this object here.



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Here we see that the name is iPhone 6 s.



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So let me show the emulator.



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It says The name is i-Pad.



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Why.



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It is actually outputting the value of this tablet computer.



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The name of this tablet computer to this screen.



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Not the name of this actually sponsored computer which is iPhone 6.



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These six actually or you can see that for example the type of the keyboard is actually a virtual keyboard.



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I actually forgot to put r here but you can see that here.



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You can't actually see this value here.



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So it is actually overlaid.



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In other words it is overwriting the values of these smartphone computers.



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So let me actually correct this value here.



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Now I'm going to actually tell you why.



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First I want to actually let you know about debugging in Android.



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So in order to actually debug that application we need to use the break point.



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So what is a breakpoint here.



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A breakpoint is actually a little red circle that we put here inside this a left side bar here inside



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is actually a gray area here.



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So look at this line of code here in line number 42 and go inside the left sidebar in line number 42



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and just click on it and now you can see that we have this letter actually read.



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This little red circle here.



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So this is actually Bridgeport.



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So this means that we had to stop the flow of the application we are going to stop the execution of



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the application from this line of code here.



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So in this way we are going to control the flow of the application that the execution of the application.



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So now at the top menu here you can see that we have this option.



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It says debug app right and then click click on it.



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Just click on it and it's going to show you this message it says lunching at to switch from run to debug.



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The app has to restart.



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Continue yes click on restart app and then choose an emulator here and then click on OK let's wait a



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little bit here.



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So now you can see that our application is actually into the debug mode here.



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Now let's see actually what's going on here.



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Let me show you the line number first the two here.



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So now here we have actually you can see this de-bug area.



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We have some options.



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The first one is actually this button that says step over.



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The second option the second button actually is step into.



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Right.



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So now let's for example if we actually click on this step into it's going to go inside the execution



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it's going to go inside the constructor of this smart phone computer class and it's going to actually



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assign these values.



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For example the name the type of the screen the type of the keyboard and the operating system and all



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the others other values.



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So let's click on this that into in order to see what happens.



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So as you can see it actually went into the smartphone computer constructed inside this Mathman computer



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class and the first line that is going to be executed is this one.



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So we have another.



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The button insists that over.



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So what does that over do.



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This that over is going to actually execute this line of code in its entirety.



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Right.



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Sort of step into it can actually go into the declare it into the declaration of the constructor.



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Or of a specific method.



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But step over is going to actually execute that's a line of code in its entirety.



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So let's actually click on the step over button here and let's see what happens.



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So now as you can see this line of code is actually executed in its entirety.



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This means that the name is passed.



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The screen is passed and the keyboard is passed to the constructor of the superclass which is going



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to be the computer class.



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Right now it's actually highlighting this constructor again.



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Let's click on this.



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Step over button again.



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So now it's going to execute this statement is going to actually see if the power that is passed to



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is constructed is actually less than or equal to zero or not.



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So the C.P.R. power that is passed is actually the 500.



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If I could hover over to if you power it has Sebille power is 500.



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And let me show you the emulator.



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So here.



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It's not going to show us the value because we are in the debugging mode.



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We need to actually go into the smartphone computer.



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We need to go into that main activity class actually and inside this uncreate Meffert we need to look



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at this much smarter computer construct that we can see that the value of the Sibiu power that is passed



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is actually 500.



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Right.



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So let's go back to smartphone computer so we can see this value here.



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So this a solution here evaluates to false.



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This means that this statement here is not going to it's not going to be executed.



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And as a result this exception here is not going to be actually up front.



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So let's click on this so that over again as you can see this statement is not executed because the



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Sibiu power is great is actually greater than zero here and we have the ram.



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So let's actually look at the value of the Ram.



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Let's click on this that over.



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If we actually show it here the value of these tablets actually hovered over this and I'm here and you



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can see that the value of the ramp is actually not actually less than or equal to zero.



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Right.



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So now it's going to execute this line of code here the operating system.



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So now it's just highlighting this line of code and this means that this line of code is about to be



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executed.



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So that's why you can see that it says the operating system now is not.



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Let's step over.



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In order to execute this line of code in its entirety.



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So now you can see that the operating system is IOAS.



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Why.



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Because this line of code is now executed.



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Right now it's about to execute this thing and I've got here subpoena power.



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Now it is actually zero.



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If we actually execute isn't enough what is going to assign 500 to the CPO power instance variable.



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Let's click on this is that over.



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Now we can see that the spew poverty's 500 here and now it's about to execute this line of code.



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Now Ram is 0 right.



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Let's click on this that over to execute this line of code here.



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Let me actually click on that over.



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So now we can see that the van is 400.



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Right.



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So this line of code is also executed and now it actually reached to this end in the curly braces is



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constructed.



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If I click on this step over it again it's going to go back to the main activity class and it's going



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to highlight that line first to exit.



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You know that will actually allow us to execute that line of code in it's in it's actually entirety.



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Let's step over.



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So now you can see that this line of code here is actually executed in its entirety.



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And now it's about to execute this line of that tablet computer right.



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So in the debugging mode you are actually in complete control of the execution of the program.



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We can't completely control the flow of the program that which line of code is actually executed at



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the moment.



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So this line of code is executed and these values are passed.



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So now it's about to execute this line of code tablet computer.



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Let's actually look at these values that I is the name resinous screen virtual keyboard Iowas and these



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values right.



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If I click on this step over we can see that this line of code is actually executed in its entirety.



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But if I actually wanted to look at the constructed of the tablet computer class and if I wanted to



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see how that constructed is actually executed I needed to click on this step into right instead of step



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over.



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So now it's going to introduce a new design of got here.



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So the problem of our application is not actually related to the performance because the problem is



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actually related to the smartphone computer and the values of the tablet computer is actually overriding



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the values of our smartphone computer so we need to solve that so we don't have to actually be worried



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about these lines of code that are related to the performance.



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So I just need to click on this that over here multiple times in order to execute these lines of code



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in their entirety.



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And now let's actually look at this at 8.



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This is very important.



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The problem is here actually so here we have an array of computer objects.



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Right.



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So here we actually specify the size of this area which is going to be four.



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This means that these are it can only accept four objects of type computer.



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Right.



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Let's click on this.



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Step over in order to execute this line of code in its entirety so you can see that we have an array



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of objects and we haven't still initialized this out if we just specify that this area can hold for



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objects.



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It's going to secure this line of code now in line number 44.



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We are going to assign in the index zero of this at a the value of this desktop computer right let's



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click on it.



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So now that this computer is assigned in the index zero of these computers at it you can see this value



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here.



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This computer right now it's going to include this line of quote.



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Laptop computer is going to be assigned into the index.



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One of these computers at.



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Let's click on this.



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Step over it in order to execute this line of code in its entirety so you can see the value here.



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Right now it's about to execute this line of code here in line number 46.



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It's going to assign the value of this smartphone computer to the index number two of these computers



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at a.



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Let's click on this.



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Step over.



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Now you can see that the smartphone computer is actually assigned into their index number to of this



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computer.



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And now finally we have the tablet computer which is going to be assigned to the index number three



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of these computers and let's get to kind of step over.



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So now these lines of code are actually executed.



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So look at this for this enhanced for loop here.



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The problem is actually occurring here.



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So now it's going to actually look at this array and it's going on just for example.



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See that it's going to iterate over all of the computer objects.



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For example the desktop computer a laptop computer a smartphone computer or a tablet computer.



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It's going to iterate over all these objects and it's going to actually look at these conditions and



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it's good to see what each one of these conditions are met and it's going to execute those if statements.



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So the first computer object that is inside of these computers is actually a supercomputer.



187

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So remember arrays are actually on an ordered collection of values that this means that the order matters.



188

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Right.



189

00:11:10,210 --> 00:11:16,660

When we assign this computer into the index 0 this means that this computer is the first computer inside



190

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the site.



191

00:11:17,500 --> 00:11:24,240

So it is going to actually execute when it is going to actually execute these enhanced for loop.



192

00:11:24,700 --> 00:11:30,030

The first computer Optik is actually there's that computer you are completely sure about that.



193

00:11:30,040 --> 00:11:31,420

So let's click on this.



194

00:11:31,420 --> 00:11:33,000

Step over.



195

00:11:33,140 --> 00:11:33,940

So just click on.



196

00:11:33,970 --> 00:11:34,790

Step over.



197

00:11:34,930 --> 00:11:39,070

And now it can actually execute this statement inside this enhanced for loop.



198

00:11:39,340 --> 00:11:44,990

So the first object is this computer right so it can actually look at this computer variable here.



199

00:11:45,100 --> 00:11:49,560

So you know that this is going to be executed for each object inside these computers.



200

00:11:49,690 --> 00:11:51,130

The first one is this computer.



201

00:11:51,130 --> 00:11:55,580

So it's going to look at this object is value but that holds the first object and say this computer's



202

00:11:55,580 --> 00:12:03,240

Ali is going to see that OK if this computer object is actually an instance of type desktop computer



203

00:12:03,310 --> 00:12:08,400

this instance of means that this computer is actually type this computer.



204

00:12:08,430 --> 00:12:15,230

So it is actually right because this computer we have this desktop computer instance right.



205

00:12:15,270 --> 00:12:19,820

It is actually the desktop computer so this condition here this expression evaluates to true.



206

00:12:20,020 --> 00:12:23,320

And it's going to execute the lines of code inside this statement.



207

00:12:23,350 --> 00:12:24,360

So let's click on this.



208

00:12:24,370 --> 00:12:29,560

Step forward in order to execute this statement let's click on it and now we can see that this condition



209

00:12:29,560 --> 00:12:30,230

is met.



210

00:12:30,250 --> 00:12:32,580

This is the second version is actually true.



211

00:12:32,680 --> 00:12:35,470

So now it went into the curly braces of this statement.



212

00:12:35,590 --> 00:12:38,040

So he's going to ask you this then I've put in a number of the free.



213

00:12:38,200 --> 00:12:39,110

Let's click on this.



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00:12:39,130 --> 00:12:40,540

Step over.



215

00:12:40,540 --> 00:12:45,820

Now you can see that it's going to say that it's going to output.



216

00:12:45,900 --> 00:12:49,000

It's going to create this object here let's can't step over.



217

00:12:49,000 --> 00:12:53,080

So it's going to get this object which is like this a computer and it is completely correct.



218

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Calling this the computer and it's going to output this value to the screen.



219

00:12:57,000 --> 00:13:02,770

This THC this computer that's set text cut into this computer that was three in is going to call the



220

00:13:02,770 --> 00:13:04,960

twisting of the candidates the computer.



221

00:13:04,960 --> 00:13:06,120

Let's go step over.



222

00:13:06,210 --> 00:13:09,430

Now is it actually executed this line of code.



223

00:13:09,550 --> 00:13:12,910

So now it's going to actually look at this condition here.



224

00:13:12,940 --> 00:13:19,170

If the computer is actually an instance of laptop computer so desktop computer is not an instance of



225

00:13:19,180 --> 00:13:20,420

laptop computer wide.



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00:13:20,440 --> 00:13:26,380

So let's go into the computer class here and you can see that the desktop computer is actually an instance



227

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of computer class not actually a laptop computer.



228

00:13:30,310 --> 00:13:35,770

So let's actually go back to the main activity class so here then it's his computer which is actually



229

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a desktop computer is instance of laptop computer.



230

00:13:38,620 --> 00:13:41,080

This expression he had evaluates to false.



231

00:13:41,260 --> 00:13:43,960

So it's not going to actually execute this line of code here.



232

00:13:44,020 --> 00:13:44,410

Right.



233

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It's not going to execute this statement this if.



234

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He is actually going to be skipped.



235

00:13:49,180 --> 00:13:50,580

Let's step over.



236

00:13:50,650 --> 00:13:53,240

So now you can see that this statement is actually skewed.



237

00:13:53,290 --> 00:13:55,920

So nice going to do look at this if statement here.



238

00:13:56,050 --> 00:14:00,190

If the computer which is actually this that computer is an instance of a smartphone or a computer.



239

00:14:00,190 --> 00:14:02,410

So again this explosion evaluates to false.



240

00:14:02,560 --> 00:14:04,120

Let's step over.



241

00:14:04,150 --> 00:14:09,070

Now you can see that this statement here is actually skipped and it's going to finally look at this.



242

00:14:09,220 --> 00:14:10,750

This statement here.



243

00:14:10,750 --> 00:14:14,230

So it's going to say that if the computer is an instance of tablet computer.



244

00:14:14,230 --> 00:14:19,370

So again this expedition evaluates to false because this computer is not actually an instance of tablet



245

00:14:19,390 --> 00:14:19,960

computer.



246

00:14:20,050 --> 00:14:24,490

So again if I on this step over this if statement is skipped and it's going to actually look at this



247

00:14:24,490 --> 00:14:26,920

condition here it's going to look at this for loop here.



248

00:14:27,070 --> 00:14:32,200

So because this for enhanced for loop is going to be executed for each object that we have inside these



249

00:14:32,200 --> 00:14:33,160

computers.



250

00:14:33,370 --> 00:14:39,910

Now it's actually time for this second object inside this body which is going to be laptop computer.



251

00:14:39,910 --> 00:14:40,610

Right.



252

00:14:40,640 --> 00:14:44,690

So now let's click on that over and it's going to actually look at this condition.



253

00:14:44,700 --> 00:14:50,380

If the computer which is which is actually a laptop computer is an instance of this computer which is



254

00:14:50,560 --> 00:14:56,480

not because laptop is not on this computer so it is a split and evaluates to false here.



255

00:14:56,650 --> 00:15:00,200

If I click on step over you can see that this statement is actually skipped.



256

00:15:00,310 --> 00:15:05,170

And now it's going to say could this if statement here if the computer is an instance of laptop computer



257

00:15:05,170 --> 00:15:06,500

which is actually true.



258

00:15:06,520 --> 00:15:11,570

So it's going to actually execute the lines of code that are inside of the curly braces of this if statement.



259

00:15:11,570 --> 00:15:12,890

This could this step over.



260

00:15:12,910 --> 00:15:19,320

You can see that this line up with it is executed here and the computer is of type Lepp laptop computer.



261

00:15:19,360 --> 00:15:23,180

And if I click on to start over again you can see that now it's going to actually execute this thing



262

00:15:23,180 --> 00:15:27,670

and I've got the laptop computer that said text Cudlitz laptop computer that was stream is going to



263

00:15:27,670 --> 00:15:32,400

call the twisting Meffert of the laptop computer and it's going to output that value to the screen.



264

00:15:32,680 --> 00:15:35,280

So let's click on step over again.



265

00:15:36,030 --> 00:15:41,430

In order to actually execute the other statements you are because we need to do that here and you can



266

00:15:41,430 --> 00:15:43,450

see that they get this expression of too far.



267

00:15:43,450 --> 00:15:46,910

So if this statement is not going to execute it's not going to be executed.



268

00:15:46,920 --> 00:15:49,900

And again we have this condition so again it is going to be false.



269

00:15:49,950 --> 00:15:53,900

If I click on that or you can see that this statement is also skipped.



270

00:15:53,940 --> 00:15:58,910

And now again here it's going to actually highlight the line of what is enhanced for loop.



271

00:15:58,920 --> 00:16:03,480

Now it's time for the word object and say these computers right inside these computers are actually



272

00:16:03,480 --> 00:16:09,370

in the Smart smartphone computer object that is in their index number two of these computers at a.



273

00:16:09,570 --> 00:16:11,810

So here let's click on it.



274

00:16:11,850 --> 00:16:12,770

Step over.



275

00:16:12,810 --> 00:16:17,880

So again this expression here evaluates to false because the smartphone computer is not an object of



276

00:16:17,990 --> 00:16:19,200

this stop computer right.



277

00:16:19,200 --> 00:16:23,740

So they said if they find it's going to be actually skipped Let's get that over so you can see this



278

00:16:23,890 --> 00:16:29,930

is skipped skipped and the lines of code inside the curly braces of this is if statement is not executed.



279

00:16:30,030 --> 00:16:34,530

And we have this condition if the computer is actually on a smartphone computer we can see this computer



280

00:16:34,530 --> 00:16:35,020

here right.



281

00:16:35,020 --> 00:16:36,110

It says iPhone 6.



282

00:16:36,450 --> 00:16:41,580

If the computer which is actually a smartphone computer is an instance of tablet laptop computer.



283

00:16:41,580 --> 00:16:42,600

So it is not.



284

00:16:42,660 --> 00:16:45,230

So this expression evaluates the FARs and it's going on.



285

00:16:45,450 --> 00:16:50,940

Skip this if statement if we actually click on this step over so you can see that is if statement is



286

00:16:50,940 --> 00:16:51,670

actually skipped.



287

00:16:51,870 --> 00:16:53,660

And now we have this statement.



288

00:16:53,730 --> 00:16:55,890

Look at this statement this is very important.



289

00:16:55,890 --> 00:17:01,470

It says if the computer is actually an instance of a smartphone or a computer which is actually completely



290

00:17:01,470 --> 00:17:05,640

true because we have iPhone success and it is off the smartphone computer.



291

00:17:05,640 --> 00:17:11,000

So now it's going to execute the lines of code inside this if statement if I could kind of start over.



292

00:17:11,010 --> 00:17:15,660

Now it's going to try to get this object the current smartphone computer here is going to cast it to



293

00:17:15,870 --> 00:17:17,490

our smartphone computer object.



294

00:17:17,550 --> 00:17:23,010

And now if I could start over again it's going to output the value of the twisting effect of this smartphone



295

00:17:23,010 --> 00:17:28,110

to computer screen TXI the smartphone computer that takes the current smartphone can beat it or twisted



296

00:17:28,110 --> 00:17:33,430

it so you can see that these values for example is iPhone 6 s here right.



297

00:17:33,450 --> 00:17:36,200

So these values are going to be outputted to the screen.



298

00:17:36,210 --> 00:17:42,990

The problem happens when they're actually the tablet computer is going to be actually identified.



299

00:17:42,990 --> 00:17:46,830

So for now let's actually just click on the step over.



300

00:17:46,890 --> 00:17:51,030

So first let me actually to go into the smartphone computer class and let me show you that this smartphone



301

00:17:51,080 --> 00:17:53,750

computer class is an instance of type.



302

00:17:53,840 --> 00:17:58,080

Actually it is inheriting from the computer class.



303

00:17:58,220 --> 00:18:02,900

So this means that the smartphone or computer for instance is actually an instance of the computer class



304

00:18:02,960 --> 00:18:03,710

also.



305

00:18:03,740 --> 00:18:04,390

Right.



306

00:18:04,730 --> 00:18:09,440

So let's go back to the main activity class and now it's about to execute this line of what if the computer



307

00:18:09,470 --> 00:18:14,450

which is actually a smartphone computer we can see that your right is actually an instance of that tablet



308

00:18:14,450 --> 00:18:16,310

computer which is not.



309

00:18:16,480 --> 00:18:22,600

It's going to actually skip this statement because this if statement this expression evaluates to false.



310

00:18:22,610 --> 00:18:27,560

If I can step over we can see that this statement is actually skipped.



311

00:18:27,800 --> 00:18:30,620

And now it's time for the final object inside this area.



312

00:18:30,650 --> 00:18:31,980

This is very important.



313

00:18:32,150 --> 00:18:33,600

Pay your attention here.



314

00:18:33,620 --> 00:18:34,710

This is very important.



315

00:18:34,730 --> 00:18:40,700

Now we have the tablet computer in the index number free which is going to be the final objective for



316

00:18:40,970 --> 00:18:41,720

the Forth object.



317

00:18:41,720 --> 00:18:43,700

And so these Adye tablets computer.



318

00:18:43,850 --> 00:18:46,100

So now let's step over.



319

00:18:46,100 --> 00:18:50,500

So the tablet computer is not an instance of this computer right.



320

00:18:50,540 --> 00:18:53,950

So this statement here is going to be skipped completely.



321

00:18:54,050 --> 00:18:59,130

It's not going to execute this statement because you can see that the computer is of type i-Pad.



322

00:18:59,210 --> 00:18:59,750

OK.



323

00:18:59,930 --> 00:19:05,290

So you can see that this statement is going to be Skipp politically can step over.



324

00:19:05,300 --> 00:19:09,150

So this statement is not executed and now it's going to actually look at this if statement.



325

00:19:09,260 --> 00:19:15,440

If the computer is an instance of laptop computer so it is not because laptop it because actually tablet



326

00:19:15,470 --> 00:19:17,180

is not an instance of laptop computer.



327

00:19:17,180 --> 00:19:20,010

So this statement here is also going to be skipped.



328

00:19:20,060 --> 00:19:21,900

Let's go actually call and click on this.



329

00:19:21,900 --> 00:19:25,340

Step over here and now look at this one here.



330

00:19:25,340 --> 00:19:27,790

This is actually the cause of the problem.



331

00:19:27,790 --> 00:19:29,840

This is the source of the error.



332

00:19:29,840 --> 00:19:37,280

It says if the computer which is actually a tablet computer computer is an instance of type smartphone



333

00:19:37,310 --> 00:19:38,330

computer.



334

00:19:38,330 --> 00:19:42,560

So it is actually this statement here is completely true.



335

00:19:42,560 --> 00:19:44,450

This expression is completely true.



336

00:19:44,450 --> 00:19:45,440

Why.



337

00:19:45,470 --> 00:19:46,320

Let me show you that.



338

00:19:46,430 --> 00:19:52,880

Let's go into the tablet computer class and here you can see that the tablet computer is extending from



339

00:19:52,880 --> 00:19:55,070

the top smartphone computer class.



340

00:19:55,070 --> 00:20:01,490

So this means that there is an ease our relationship between these two classes a tablet computer is



341

00:20:01,550 --> 00:20:03,890

our smartphone computer right.



342

00:20:03,890 --> 00:20:06,260

We specify that explicitly here.



343

00:20:06,350 --> 00:20:07,360

Right.



344

00:20:07,370 --> 00:20:13,640

So this means that an instance of type tablet computer is going to be actually of type tablet computer



345

00:20:13,940 --> 00:20:17,730

and it is going to be also of smartphone computer.



346

00:20:17,780 --> 00:20:20,680

So because there is an inheritance relationship here.



347

00:20:20,840 --> 00:20:27,230

So let's go back to the main activity class and here if I actually click on the step over because this



348

00:20:27,230 --> 00:20:32,720

actually this expression evaluates to true it's going to execute the lines of code here in say the collaborators



349

00:20:32,810 --> 00:20:33,920

of this statement.



350

00:20:34,040 --> 00:20:34,670

Let's click on.



351

00:20:34,690 --> 00:20:39,770

Step where we can see that this expression evaluates to true and it's going to actually execute this



352

00:20:39,770 --> 00:20:40,670

line of what here.



353

00:20:40,690 --> 00:20:42,490

Current smartphone computer.



354

00:20:42,620 --> 00:20:48,070

In other words this statement should not be executed because this is the cause of the error.



355

00:20:48,080 --> 00:20:52,360

If I click on this system over again and now it's going out with this value it's going I think it is



356

00:20:52,360 --> 00:20:58,170

done with here and it's going to output the value of the tablet computer to the text view of the TXI



357

00:20:58,190 --> 00:21:01,570

the smartphone computed of the smartphone computer actually takes a view.



358

00:21:01,760 --> 00:21:08,240

So it's going to call the twistings method of the tablet computer instead of the smart phone computer.



359

00:21:08,240 --> 00:21:12,440

Right because the tablet computer is an instance of smart phone computer.



360

00:21:12,560 --> 00:21:16,850

If I clicked on this start over again and now it's going to actually look at this statement so again



361

00:21:16,880 --> 00:21:23,800

because tablet computer which is actually this one is an instance of top of tablet computer also here.



362

00:21:24,050 --> 00:21:28,850

So it's going to look at these conditions so it this expedition here evaluates to true and it's going



363

00:21:28,850 --> 00:21:30,580

to execute this statement also.



364

00:21:30,710 --> 00:21:33,950

So we can see that this is low enough to here is about to be executed.



365

00:21:34,010 --> 00:21:38,710

And now this one is going out but the value of the tablet computer with it takes the tablet computer.



366

00:21:38,870 --> 00:21:44,300

So let's go because that over and now we can see that all these objects is executed and if you click



367

00:21:44,300 --> 00:21:50,300

on that over you can see that it's actually to reach the final to the ending curly brace of this uncreate



368

00:21:50,300 --> 00:21:50,940

method.



369

00:21:51,230 --> 00:21:54,540

So now you can see that what is the cause of the error.



370

00:21:54,600 --> 00:22:03,670

You actually we actually found out that where the error actually exists the error exists here inside



371

00:22:03,730 --> 00:22:06,620

this statement computer instance of smart phone computer.



372

00:22:06,620 --> 00:22:12,590

So how we can solve this problem in order to solve this problem inside this statement is to create another



373

00:22:12,770 --> 00:22:20,350

statement so if inside parent says here let's actually put a bank here.



374

00:22:20,530 --> 00:22:26,310

These exclamation mark because this exclamation mark is going to reverse the value of a boolean value



375

00:22:26,320 --> 00:22:28,160

if it is actually true it's going to make it false.



376

00:22:28,180 --> 00:22:30,350

And if it is for he's going to make it true.



377

00:22:30,680 --> 00:22:37,750

Let's put a pair of practices here and let's say if bank or exclamation marks we can we can actually



378

00:22:37,750 --> 00:22:47,020

call it bank or exclamation marks right into the apprentice's computer instead of actually tablets computer



379

00:22:49,420 --> 00:22:56,110

then only in that case executes the lines of code here only in that case execute these two lines of



380

00:22:56,110 --> 00:22:56,750

code here.



381

00:22:57,010 --> 00:22:57,260

Right.



382

00:22:57,280 --> 00:22:58,800

So what does this mean.



383

00:22:58,810 --> 00:23:03,510

So this means that the computer is actually off the instance is smarter than a computer.



384

00:23:03,520 --> 00:23:04,550

So it is OK.



385

00:23:04,660 --> 00:23:06,020

It this statement.



386

00:23:06,070 --> 00:23:08,580

And then it's going to go inside the curly braces of this statement.



387

00:23:08,680 --> 00:23:16,270

And it's going to look at this if statement here is going to see that if the computer is not looking



388

00:23:16,290 --> 00:23:22,990

at this bank here is if the computer is not an instance of tablet computer exec could these two lines



389

00:23:22,990 --> 00:23:23,510

of code.



390

00:23:23,650 --> 00:23:27,040

So here we are using that nested if statements here.



391

00:23:27,040 --> 00:23:34,120

Right here we want to make sure that the computer is actually or is not a tablet computer and only in



392

00:23:34,120 --> 00:23:39,330

that case we want to output these values the value of the smartphone computer to the screen.



393

00:23:39,670 --> 00:23:45,390

If I actually don't put this statement here because tablet computer is an instance of type smartphone



394

00:23:45,430 --> 00:23:50,260

computer it's going to actually secure these lines of code and it's going to overwrite the value of



395

00:23:50,260 --> 00:23:52,830

the smartphone computer on the screen.



396

00:23:52,840 --> 00:23:55,900

So now the problem is going to be solved.



397

00:23:55,900 --> 00:23:57,750

Let me actually fall into the break point.



398

00:23:57,750 --> 00:24:02,770

So in order to do the breakpoint you can't just click on it it just they can just click on it and now



399

00:24:02,770 --> 00:24:04,030

the breakpoint is gone.



400

00:24:04,360 --> 00:24:05,770

Let's run our application.



401

00:24:05,770 --> 00:24:10,810

Let me actually click on the start and let me show you the emulator.



402

00:24:10,870 --> 00:24:14,600

So here I just need to actually select one of these devices and then click on OK.



403

00:24:14,710 --> 00:24:20,890

So here you can see that the problem is completely solved and we can see this iPhone 6 as retina screen



404

00:24:21,130 --> 00:24:23,930

virtual keyboard power lab performance.



405

00:24:24,010 --> 00:24:29,230

And we have the tablet computer which is when it's actually specific value use your iPad retina screen



406

00:24:29,380 --> 00:24:32,850

virtual keyboard Sibiu power wrap screen size performance.



407

00:24:32,890 --> 00:24:33,520

Right.



408

00:24:33,900 --> 00:24:39,490

So now the problem is completely solved and we just needed to actually use this statement inside this



409

00:24:39,640 --> 00:24:40,230

statement here.



410

00:24:40,240 --> 00:24:42,440

We have actually a nested IF statement here.



411

00:24:42,490 --> 00:24:47,950

And I was thinking that if the computer that is passed here is not of type tablet computer only in that



412

00:24:47,950 --> 00:24:51,280

case we are going to execute these these two lines of code here.



413

00:24:51,540 --> 00:24:51,980

Right.



414

00:24:53,020 --> 00:25:00,340

So that's it if you want to you can actually create again a breakpoint here in line in line number actually



415

00:25:00,620 --> 00:25:01,560

for 30.



416

00:25:01,570 --> 00:25:07,390

Or it can actually create a regimented in line number 43 and you can control the execution of the program



417

00:25:07,450 --> 00:25:10,820

and see how these lines of code are actually executed.



418

00:25:10,870 --> 00:25:18,040

And I actually completely suggest you to actually do this to practice on your debugging skills because



419

00:25:18,070 --> 00:25:23,150

it is a very important skill in skill in Android If you want to become a professional and the developer



420

00:25:23,170 --> 00:25:28,500

you have to be proficient in the bug in your Android applications.



421

00:25:28,930 --> 00:25:29,540

So that's it.



422

00:25:29,560 --> 00:25:34,300

If you have any questions please post the discussion in the course and then I'll do my best to answer



423

00:25:34,330 --> 00:25:35,270

all of your questions.



424

00:25:35,410 --> 00:25:38,610

Thank you very much for watching and I'll see you in the next tutorial.