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Welcome back.

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And this video, we're going to look into view binding because we're going to keep on using view binding

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from now on in the course.

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So far, we've only used find view by ID and there is a better way around it if you want to get access

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to items in your user interface.

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And also, we're going to get rid of the action bar.

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So let's start with the action bar problem slash situation because there's not really a problem.

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It's just something that we need to fix.

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And in the manifest, you could see that we are using the seven minutes workout theme.

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And let's jump into it into our themes example where we can then change it to, well, from dark action

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bar to actually no action bar.

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OK.

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And this will replace the action bar from, well, get rid of the action bar, basically.

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So that's one thing.

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Let's run the application once again.

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You see how it's going to look now, before and now you see how it looks after.

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So we don't have this entire action bar here, which allows us to go back or whatever and says the name

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of the application and so forth.

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We don't have that anymore and we don't need it.

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All right.

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And now let's look into view binding, OK, because we are going to use vue binding from now on and

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in order to use vue binding, we need to set a couple of things up.

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First of all, in the cradle file.

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For our app.

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We need to add to built settings.

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He had an options build types and so forth inside of Android.

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We add build features.

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So where we need to use this curly brackets like so and say few binding.

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True.

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All right.

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So we're basically saying we want to use view binding, we're activating it.

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Once done, we sink the file, so synchronize it and now we can use view binding.

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Now, inside of our main activity and the general inside of activities, we can now go ahead and use

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view binding.

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Therefore, how you go about it is you create a new variable.

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And let me get rid of this as well here.

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VAR binding colon and then you use the name of the activity.

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So here activity main binding.

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OK, so activity main is the XML file name and then you have the binding keyword.

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So that's generally how it works.

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This is automatically generated for each activity that you have.

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This activity is called main activity.

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So if you have an activity, for example, exercise activity, then it would be called activity exercise

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binding.

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All right.

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So now we need to make it the knowledgeable and assign null to it.

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We need to import it as well.

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So let's import this class and you will find that it's now available here under data binding activity

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mean binding.

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And this is the name that I have for my project, but the directory for the project so that we can use

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this binding.

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So instead of setting the content view in here, we're going to set the content you off to preparing

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our binding object.

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So our binding object at this point is null as you see, and we can use activity mean binding and dot

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inflate in order to now use their layout inflator to inflate the XML file.

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So what it's going to do is it will basically prepare our binding object that we can now use it and

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say binding dot root here.

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So our set content view will now set it in a different way.

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So this was how it was set before, right?

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It's just said OK, use activity in XML, which is still fine, but this is the view binding approach.

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So what it basically happens is it says use this XML file called activity main and inflate it with a

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layout and Fletcher and store it inside of this binding object and now use the root of this binding

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object, which is the main activities some L files root container, which is this constraint layout.

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OK, so the constraint layout is the root of this entire binding object, but now what we can do is

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instead of using the finite view by idea approach like we did here, we can go ahead and use view binding

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instead.

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So let's set that up real quick.

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Therefore, we can just say binding that if a start and dart set on, click listener.

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OK, so we don't need to create this variable anymore.

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We don't need to create any variable for our user interface items.

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We can directly access their IDs inside of this binding object because, as you know, it contains this

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entire XML file, which also contains the individual ID so we can now access the ID directly, even

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though we need to use question marks because the binding object is another bowl and the frame layout

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is also infallible.

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So at this point, we can go with it.

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So we are well, you see, we don't have to do this stuff anymore, which we had to do quite a bit.

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And also, if you wanted to do now, use this frame layout.

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Outside of this method of this concrete method, we can still use view binding.

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We don't have to set up this frame layout globally here at the top, for example, and then assign it

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inside of the on create method and then we can only use it.

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Now we can now use it throughout the entire file using this approach here, which is very cool.

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Now, whenever you want to use view binding in your project, really make sure that you also use the

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on destroy method where you.

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Said binding back to null.

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OK, so use the standard approach of the UN destroy, but then also make sure that binding is reset

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to null.

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Otherwise, you might run into problems.

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OK, so this is just a clean way to unassigned a binding to avoid memory leak.

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OK, so what is the purpose of view binding?

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Well, the implementation is shorter and concise.

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It is faster and more efficient during compile time.

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It is a safer alternative because it ensures only the views interconnecting lay out are being referenced

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because otherwise what could happen is, let's say we have an I.D. We call it false start.

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But then in another XML file, we also have, I feel, start and then by accident, we are accessing

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the wrong EFL's start and this would crash our application.

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But now, with view binding, we are making sure that we are only specifically accessing the items.

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The IDs of the file that fits to our exome L fits to our class.

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So our main activity has an example assigned to it.

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And only of that example, we can now access the IDs, which we now do because find view by ID works

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throughout all files.

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It doesn't just work for this particular file.

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So if we had an file start in another XML file that has nothing to do with our activity in our application

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would crash.

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OK, so these are a couple of good reasons, I believe, and this is also the recommended approach.

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So view binding how this whole thing is called as the approach that Google recommends for you to use

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when it comes to applications that you're building from now on.

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OK, so that was it for this video and the next one, we are going to look at how to add to exercise,

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screen and use intents and customizing our toolbar.