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Hi everyone in this directory all of you are going to go ahead and create another Android application.



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So just click on this.



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Start in your Android studio project and for the name of our application name as you can see here just



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type in here app 50.



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OK so let me actually delete this name here app 50 and here click on next.



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And here are the minimum STK choose AP is 16 Android 4.1 jelly bean.



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And then click on next and here choose empty activity next and he can finish.



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So now as you can see our application is actually created.



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So let's actually get double click on the rest folder here and then double click on the layout folder



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and here's double double click on this activity underline made that example.



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So here as you can see this is the user interface of our application here.



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So just select this hello world takes you here and then press on delete key on your keyboard.



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And now let's say you did write a linearly or two vertical at the center of this relative lay out and



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then let's actually find the check box which it has you can see here we have this checkbox component



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here inside these widgets folder.



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So just select it and put it at the center of this linearly 20 call and double click on it.



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So as you can see here the text is new checkbox and the IDs checkbox.



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And I think that's enough for this tutorial so you can actually leave it as default.



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OK.



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So I'll just press enter on your keyboard and now there's actually to go inside is main activity that



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double file here and here let's actually declare our checkbox object so here can just type in checkbox



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and the name of my checkbox is going to be checkbox.



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Assignment operator and here I'm going to recast this object to a checkbox object find view by OED or



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that ID that checkbox.



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OK so here as you can see I actually created this checkbox object inside my class.



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OK.



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You can actually do this here inside your class or you can actually only declare your checkbox object



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in your class and in an instant sheet your checkbox object inside your uncreate Smurfette.



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So here I have just been checkbox here.



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Assignment operator and then I can actually cast this object to a checkbox object find view by id odd



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that Id dot checkbooks.



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OK.



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And at the end the end of your statement you need to put a semicolon here.



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So now I want to talk about shared preferences in Android.



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So first of all let's actually run our project now and see what happens.



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So now as you can see our application is running on the emulator here.



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So if I click on this checkbox here let's see what happens.



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And now as you can see the search box is actually checked.



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And if I click on the tick box here again.



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Now this checkbox is actually checked off.



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Now I haven't actually check check this checkbox here.



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And then when I actually click on this back button here soon as I can see the undestroyed if it is actually



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called and our application is actually no longer in the memory.



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And if we want to actually open our application again here as you can see now as you can see that as



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you can see here this check box is actually the checked of in the last time that they actually opened



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this application.



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I actually checked just this checkbox.



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OK.



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And I want to actually save this state.



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So I want to actually check this checkbox and when I actually click on the back button and the application



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is actually destroyed inside our memory when I go back to my application of and I actually open my application



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again.



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I've gone this state here to be saved.



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I want this state to be saved and I want to access that state.



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So how I can do that.



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And that's the purpose of this tutorial in this tutorial.



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Want to talk about shared preferences.



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In order to actually save your save the status of your application.



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So first of all you need to actually make this checkbox here are listening to the police of the user.



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So I can't just type in checkbox that set on checked change listener here.



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So inside the practices we need to specify the context.



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So here I can just type in main activity that this.



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OK.



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And now we need to actually implement the compound button that unchecked change to listener interface.



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So here at the top after this piece of code here extends app compact activity implements and here the



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Kansas IPN compound what of it chapiters see compound button that uncheck change listen and with Capitol



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all unchecked change listen.



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OK.



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So here I have this interface.



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So we need to actually implement the abstract Smurfette that is inside of this interface in our main



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activity class.



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So here I can just type in unchecked chained here as you can see this is that this is the method that



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is inside of this interface and we are actually implementing that method in our on main activity class.



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So whenever the user clicks on this checkbox here as you can see when the user checks or uncheck this



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checkbox here or this effort here unchecked change is going to be called OK.



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So now as you can see I can just type in if it is checked and this means that if this checkbox here



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is actually checked.



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So now when I truly create these curly braces here.



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So inside these curly braces are you going to actually change this text of this check checkbox here.



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OK.



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I want to just put the text the checkbox is checked here in in place of this text view takes a view



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here OK.



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So here I can as you can see I have this checkbox here in my main activity so I can refer to the name



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of this checkbox object in my on Cheikh change method so I can just type in checkbox that set text.



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And as you can see I can actually change the text of this checkbox then this checkbox is actually checked.



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So you say the prentices I can't just put in two double quotes and I can't just type in the checkbox



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is checked OK.



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And here I actually create an else statement and this means that if this checkbox is actually not checked



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ok then I'm going to actually change the text of this text checkbox to this text box is not checked.



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So here I can't just refer to the name of this object checkbox that said text and inside Apprentice's



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Argento's type in the checkbox



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is not checked.



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OK so now let's run our project and see what happens when I take or on this checkbooks here.



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So as I can say now the application is running on this emulator.



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So now I want to check this checkbox.



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And as against can heal this checkbox is actually checked and the text of this takes checkbox is actually



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the checkbox is checked OK.



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So let's actually uncheck this checkbox and that takes these.



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The checkbox is not checked OK.



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So hopefully that makes sense and want to actually save this state.



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For example I can actually check this checkbox over want to save this state in memory.



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So when I actually click on dispatch button and the application destroys in memory and when I go back



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to my application and open my application I want that state to be saved.



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OK.



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And as you can see that state is not saved at the moment.



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So what's the solution.



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The solution is preferences in Android.



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So in order to do that first of all we need to actually override the unpause Merfeld on pause Meffert



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that is inside of the Android lifecycle on past Meffert and the on resume if.



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OK.