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OK, moving right along or is working pretty good, but now when we pull up a certain function like

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the addition thing here and then move to another one, that seems to work, but then if we go back again

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to the first one, what was originally printed is still there.

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And then it prints out another set.

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And you can see it's kind of, you know, doing a thing here and this is no good.

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So how do we fix this?

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Well, it's actually pretty easy.

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And I've showed you a couple of different ways to change things, you know, like overwrite labels or

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use the config feature to change what's in a label or a thing.

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What we can also do is just sort of.

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Destroy all of the things in a frame.

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So let's look at this again real quick, because I want you to understand what's going on here.

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So we've got our app, and so we've got basically three or four things here.

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We've got this label here.

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We've got this entry box, we've got a button, and then we've got this label here.

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So one, two, three.

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We've got four things.

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And each of these things is a child of the parent frame.

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So the frame is the parent.

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The things in the frame are the children, the children, widgets.

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So all we have to do is loop through and destroy all of those children widgets.

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Now we can look up the names for each ones, but that would be a hassle and, you know, changes from

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program to program.

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Instead, we can just sort of loop through all of the children in a particular frame.

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And that's what we're going to do in this video.

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So there's a function called dot w info underscore children and it just looks like this.

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Let me just copy and paste it.

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And what we want to do is go down to our hyd menu frames.

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Remember, this function gets fired any time one of our other functions gets fired.

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So when we call divide it, it calls that hyd menu frames function, remember from, I don't know,

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10 videos ago or so.

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And what that does is it hides all of the other frames that had already been up.

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Well, this is a great place to do this, what we need to do.

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So like I said, this is this function.

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It's the W info underscore children.

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And what we can do is just loop through each frame and then we destroy each thing.

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So let's do that so we can go for widget.

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Now, this is just a variable.

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This is a for loop with Python.

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It's not Kintyre things, just a loop thing, a python thing.

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So we create a variable.

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I'm just going to call it widget because that's what we're dealing with.

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Widgets.

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Again, it's not a counter thing.

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I'm just picking a random variable name.

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We could call it W we can call it X.

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It doesn't really matter, but it's a widget that we're going to be dealing with.

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So I'm going to call it widget.

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So for widget in and now we call our frame and let's start with the add underscore frame and then we

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can just dot w info children.

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So then we're going to loop.

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And so inside of here we can just go widget, dot, destroy.

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Right.

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So that's it.

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So this little for loop will loop through all of the widgets, the children widgets in our frame.

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So what this does is say, hey, go to the ad frame and then find all of the children in there and then

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loop through each one and then destroy each one.

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So that's all there is to it.

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So now we could just copy this and be sure that your tabbing here and not spacing.

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Remember, Python is tab sensitive.

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So one, two, three, four.

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And let's make a comment here.

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So say destroy the children widgets in each frame.

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And then down here, let's make a comment.

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Hide all frames, OK, so OK, for each of these, we need to fiddle with it.

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So this is the this will be the subtract frame and I'm just taking these names right here.

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So the next one will be multiply the frame and then finally divide frame.

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OK, so if we save this, this should work now.

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Let's go ahead and run this.

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And so we've got add and we go subtract and we go back to add and oh, it worked and it's not putting

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it again down here.

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So we could try for all of these, go back to add, back to subtract.

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Go back.

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Try and multiply.

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Go back to divide.

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And it seems to work for all of them.

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So pretty simple and a very handy little function to know.

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And that's all there is to it.

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So that's all with this video in the next video, I think will play around with the main screen of our

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app.

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So like right now it's just sort of blank here.

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So let's put a little something in there and make it look a little nicer.

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And I think we'll do that in the next video.