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Now in the last lesson,

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we saw a couple of different ways of working with tkinter widgets.

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We've already seen how we can create labels,

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so something like this, and also buttons that can be clicked and do some sort of

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action. Then we've also seen entries,

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which is basically some sort of textbox.

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And now I want to show you some of the other widgets that you can work with.

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For example, the text entry box

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which allows you to use multiple lines of text, or something like the spin box

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which is basically a sort of counter

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which lets you go up and down, and then a scale

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which is a slider

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basically that you can move along its axis and change its value.

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Then there's a check box which can be on or off basically just a tick box,

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radio buttons, and finally a list box of choices

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which you can pick from.

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So these are pretty much all the widgets that you can work with. To save you from

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typing a lot of this example

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code, I've created a tkinter widget demo Repl.it for you

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which you can go to and you can see some of the existing code that we've already

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created

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like how to create a window or how to create a label and how to create a button.

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But I want to show you some of the other features by just looking at the code.

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For example, with the entry

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we can actually insert some text for the entries to start off with.

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So notice how here we can click on it to edit it,

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but it's really got some starting text in there. So for example,

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if you wanted to create an email box,

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maybe you would write the word email to give the user a bit of a hint.

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Now you've also got a text box

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which is a large area where the user can edit.

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And this is simply created with the text widget.

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You can set the number of lines as height and the width as the width of the box.

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And you can set the text to be focused so that the cursor starts out in that

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textbox.

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And then we can insert some piece of text to begin with and we can also get hold

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of the text inside the text box using the get method. Now notice

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there's something a little bit weird

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like the end here and the end here.

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This is just an index to allow tkinter

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to figure out which particular item you're referring to and you don't have to

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change it ever. This is just the code that you use.

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You can keep the code exactly as it is here and just modify the test that you

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want to insert.

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And this 1.0 basically refers to getting hold of the text

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starting from the first line at the character zero.

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And then we've got a new widget that we've never really seen before, a spin box,

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which looks something like this.

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So you can click on the up and down to change its value and we can print out the

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value that's being changed in there by simply getting the spin box to be tied to

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a function which is called spinbox_used.

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And then we just get the value each time.

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Now a scale is also pretty self explanatory.

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You can move it up and down, and we're getting hold of the value that would

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the user is landing on by simply packing, again,

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another command into that scale when we're creating it.

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And then when that function is called,

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it actually passes over the value that the scale is currently on and that is

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what's getting printed. Next

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we've got a checkbox and we can click it on or off.

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And we can print one or zero by simply tying that checkbox to a variable.

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And this variable is something that's defined by the tkinter module as a IntVar.

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So this is actually a class.

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And once we create that object from the class,

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then we can add it to our check button when we create it,

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and that variable will keep track of the value of that checkbox. 1 for on and

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0 for off. And then we can print it out

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when that check button is used.

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Now radio buttons are useful to pick between different options.

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So normally you'd have a number of options and only one of them can be selected

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at any one time. So in this case what we do is, again,

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we create a IntVar and we tie that var to 

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each of the radio buttons that we create,

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and then we give each of the radio button a value. So this one has value 1,

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this one has value 2, and they're both tied to that radio state IntVar.

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And then when that button gets changed,

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then we can actually get hold of the radio state by calling radio_state.

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get and when you get whichever value it is that's currently selected,

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so option1 or option2. Now finally,

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we've got a list box

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which is just a list of options created from a Python list.

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We'd loop through each of the items,

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insert it to our listbox and then once the list box is used,

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we use this bind function to call this particular call back. This way

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whenever we select any of the items in here,

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it will print out and get the current selection. Now,

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a lot of this code is pretty much going to be used the same each time.

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So it doesn't really matter if you don't understand fully exactly what some of

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these weird components are.

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It's just a factor of how this tkinter library has taken this tk module and

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turned it into a Python format for us to be able to interact with it using

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Python.

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So there's a few weird bits like this listbox select or this,

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um, end being used here,

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but you can see that each line is commented and it tells you what it does.

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So you'll be able to figure out what line of code you need to write

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in order to add some text or to get some texts or how to bind a function to the

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list box and how to get hold of the value that's currently being selected.

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I recommend heading over to this link here and either downloading the code and

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opening it in PyCharm if you prefer,

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because then you can actually get a much larger version of the running program

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or alternatively,

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just have a play around with the code in here so that you understand how these

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widgets work and how you can use it basically as a pallet

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if you wanted a couple of checkboxes,

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or if you wanted a couple of a spin boxes,

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then you can just pick and choose them from this cookbook essentially

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and then you can put them into your programs when and as needed.