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Hello and welcome to part two where we will continue with the creation of the weight conversion tool

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to carry on.

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I'm going to add some lines of code that I have already pre staged.

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I have had it some more lines of code here.

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So this is the line of code I've added.

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So here we've got a variable here.

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I've set it to a string var method that means this who accept string values.

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Here again the meter's variable.

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Set it to a string file which means it again it will accept string variables.

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I've also created three main widgets for our program.

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We've got the entry where we'll type the number of feet which is this here.

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This is where we'll type the number of feet.

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OK.

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And then a label where we will put the resulting numbers of feet.

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OK.

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This label here is where we will put the result to number and got a calculate button that will we will

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press to perform the calculation which is this line of code here for each of the three widgets that

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we have created we need to do two things we need to create the widget itself and then we need to place

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it on the screen all the three widgets which are children of our main content window are created as

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instances of one of the T keys themed widget classes the same time we create them we also need to give

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them certain options such as how wide the entry should be the text the position of the text inside the

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button the entry and the label we need to assign each of them text variables so you can see the text

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variables here have attached when you create widgets they don't automatically show up on the screen.

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This is because T.K. doesn't know how you want them to be placed in relative to other widgets OK.

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So this is where the great method comes in.

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Remember when you we did in here when we were doing the frame we did a bit of greed.

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There was some greed involved in there.

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So we place each widget in the appropriate column so it could be column one two or three and also in

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the appropriate role.

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So for example row one two or three.

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We've also used this tiki option.

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You can see the sticky the sticky option says or it's used as Perspex specify how the widget will line

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up within the grid cell.

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So it does that using the direction of the compass.

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So W stands for West which means Uncle the widget to the left side of the cell W E stands for w e which

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means Uncle it to both the left and the right side and so on.

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Next we're going to add some lines of code that will create three static text label that we will use

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for the user interface.

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So I've now added the lines of code.

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These are the labels that we'll be using for the user interface.

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All the three lines of code here they do exactly the same thing for the three static text labels that

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we're adding to the user interface.

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So each one he's created and placed in the appropriate cell in the grid.

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So we've added some more line of code to finish up the user interface.

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So these are the lines of code I I've just added on.

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So let me just walk you through that.

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The first line here.

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So I'm using a for loop here.

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So that first line there basically you walk through or all the widgets that are children of our content

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frame and it will then add a little bit of padding around each.

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So the errant so so that they are not all squashed up together.

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That's what that does.

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We could have added these options to each of the Creed when we first put a test on the screen but this

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doing it this way is a more it's a nice on a shorter way.

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That way we don't write too many code.

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This line of code here that line basically tells T.K. to put the focus on our entry widget.

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So any way you see me talking about T.K. I'm making a reference to the T.K. function which is part of

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the T Kintore module.

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So this line here like I said is basically used to tell T.K. to put the focus on our entry widget that

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way the cursor will start in that field.

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It does its best to do it that way.

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So the user doesn't have to click it before starting to type.

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Let's move on to the third line which is this one here.

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The third line basically tells T.K. that if the user presses the return key enter on a window anywhere

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within the root window that should call our calculate routine.

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All right.

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So if the user should press the return key or enter a return and enter the same thing.

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So if they're pressed if you're on a window it will be enter on a Mac probably will be returned.

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So if the user should press that T.K. basically will respond by calling they calculate routine.

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OK.

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The same will happen if the user presses a calculate button and then we've got the main loop here.

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This event loop.

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This is what keeps the application running until the application is close.

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So the application we keep running on looping until it is close and it is controlled by this route.

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The main it is what controls the events that occur within the application.

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So that's set for this part in the final part in Part 3.

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We are going to create a function that will actually perform the calculation.

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Thank you for watching and see you in part 3.