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OK, in this video, I want to show you how to overwrite things and get rid of things, how to remove

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things, specifically, we're going to be looking at labels.

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So I've created a file called Forget That Pie.

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And it's very simple, actually.

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Let's just run this thing to see.

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And it's just a very basic thing here, have enter your name, we can enter our name, John Elder,

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we click the submit button.

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Hello, John Elder.

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So that's all this does.

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It's printing this label onto the screen.

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So let's look at this real quick.

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Just to walk through this code, we have.

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A label that says enter your name and I'm using the grid system here, that's why it's kind of mushed

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up in the corner like this.

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And we'll look at back in just a minute as well.

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So we have an entry box.

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We've learned how to do those.

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And that's just this box right here and a submit button and submit.

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And when we click it, it runs the submit function, which creates a new label and it says hello and

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then puts whatever you put in the box in and then grids it out onto the screen.

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So hello, John Elder.

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Pretty simple.

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Well, now, if we continue to do something here, if we went, John, for instance, and we wanted

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to click it again, it would kind of just put it on top of the other one that we already printed.

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And now it says, hello, John.

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And then the stuff you could see below it.

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This is just no good.

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So how do we kind of clear things?

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How do we overwrite things if we want?

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That's what we're going to be looking at in this video.

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Maybe, maybe the next video as well.

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See how long it takes us to get through this.

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So let's close this and let's create another button down here.

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And first, let's call it clear button.

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And this is going to be a button and it's going to go and route and the text will be clear and then

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the command will equal clear.

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Now, let's just grid this onto the screen.

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So row two, column one.

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So now we need to create this clear function real quick.

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So let's create clear function and so define clear.

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And what do we want to do?

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We want to take this Halo label.

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And we want to kind of erase it, right, so we can do this a couple of different ways, there's a function

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called Grid Forget and there's a function called destroy.

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Now, destroy destroys the thing.

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It just removes it completely.

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Grid forget hights it.

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So we'll look at both of them.

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A I usually use a grid forget and that just kind of hides it for a while and then we can bring it back

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later if we want to.

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This works also with PAC, there's a PAC forget as well, so it works the same way.

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But we're looking at grid right now, so let's go.

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Hello.

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Underscore label dot grid underscore forget.

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And this is a function so we just have to do that.

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Now if we save this, this is not likely to work and let's run this and see why.

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So if we were on this again.

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Here we can type in, John, if we submit boom and put it on the screen, if we click here, nothing

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happened and if we click exit here.

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Now we're getting this this er and it says hello label is not defined.

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And this is a scope issue.

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If you're familiar with Python or any programming in here, in this function, we created a local variable

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and it will only work in this function.

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So to try and call something and do something with it in this function, it doesn't work because this

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function doesn't know what that is.

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So we can change this.

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We can fix this a bunch of different ways.

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We can try, for instance, calling Global Hello label like that.

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If we save this, this may or may not work.

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Let's give it a try.

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So we can type something, click submit now if we click here, boom, it disappears, so that's one

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way to do it and that will usually work.

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And let's run this again.

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And play with this, so if we now type in John Elder, if we click, submit, boom, hello, John click

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boom there goes clear.

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Now, if we change this to Tim when it calls it back again, so even though we're hiding it, it's hidden.

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And then when we run the function again and it creates that label again, it puts a different thing

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on the screen.

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So that's grid.

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Forget using a button explicitly.

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You can also, like I mentioned, use, destroy and it does not the same thing, but it will delete

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it, destroy, kill it completely and no longer exists.

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For all intents and purposes though, that's kind of the same thing.

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Right.

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So we can go John, submit boom changes to Elder, bring it back, boom.

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So, you know, it kind of works in the same way for the most part, but it's just slightly different.

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And there are times when you may want to destroy a thing completely and that's how you do that.

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So that's how to do that with a button.

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But maybe we don't want to use a button.

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Maybe we want to create underscore, forget right off the bat when we click the button so we don't have

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to click a clear button, maybe when we type of thing and again the second time and just do it, maybe

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we want it to, you know, delete itself at that point.

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Well, I think we'll look at that in the next video.