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Alert!

Name: Alert!
Uploaded: 2015-08-24T16:46:53Z
Duration: 203 s
Description: Finally, we need to show an alert window when the timer runs out.

3:23 with Kenneth Love

Finally, we need to show an alert window when the timer runs out.

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The official docs for Tkinter aren't the best in the world but they'll get you started. The documentation from effbot hasn't been updated in about a decade but it's actually still mostly accurate. These are my two main resources for learning Tkinter and preparing this workshop.

More information about colors and fonts.

Terms and things

Tk() - A Tkinter application. This is what is responsible for the window or application you see on your screen. You'll end up binding most things to this.

mainloop() - The loop that keeps your Tkinter app running. This loop runs forever.

Frame - An invisible box that you can put things in.

Label - A piece of text on the screen.

Button - A button (whodathunk?!)

StringVar - A variable that holds onto a string.

IntVar - A variable that holds onto an int.

trace() - A way to follow the changes and access of a variable.

columnconfigure() and rowconfigure() - Methods to configure the number and weight of columns and rows.

pack() - Method to insert a widget in the available space.

So, we're gonna do a pop-up window, an alert window, like you do with JavaScript. 0:00

And TkInter has one. 0:04

But we can't use it from TkInter.whatever. 0:05

We have to import it on its own. 0:08

So, we'll say from tkinter import messagebox. 0:10

And there are a lot of different message boxes. 0:13

Some ask a question and the user can answer with a yes or no. 0:16

Others accept input, like a text box to take in information. 0:19

And some, like the one that we're gonna use, are just for sharing information. 0:24

So, it's just going to put out a message. 0:28

So let's go down here. 0:30

Let's make a new function. 0:33

And we're going to call it alert cuz it's our alert. 0:36

And since it's going to get triggered, as well, we need it to take args. 0:40

All right. 0:47

So, we're gonna say, if not self.time left.get(). 0:48

So, if there are no seconds left, then we want to do message box.showinfo(). 0:55

And then the title that we want on the window, 1:02

this right here says pymodoro.pi gui blah, blah, blah. 1:05

We want that to say Timer done. 1:09

I suppose it could say Pymodoro or something. 1:11

And then our message is just going to be, Your timer is done! 1:14

Super, super exciting [LAUGH] there. 1:17

Okay, but now, how do I want to fire this off? 1:21

So, we need to actually watch for stuff to happen and then fire this off. 1:24

And this really make sense to have fired whenever this runs out. 1:28

Now, I don't want to do it and update because that's weird. 1:32

I've had to watch for running conditions and make sure the start button is disabled 1:35

or the stop button is enabled, and then, it's just a lot of trouble. 1:39

So, let's not worry about that. 1:43

Let's do it with another trace. 1:44

So, if we come back up here to our init, and we have this time left. 1:47

Let's do self.time_left.trace, and 1:53

we want whenever this is written to, to call self.alert. 1:57

So, whenever our update method changes the number of seconds that are left, 2:03

our alert method checks to see if it should fire the message box. 2:07

Let's try this out. 2:12

And I have a feeling this may end up firing off a second or 2:14

two early due to the order of stuff. 2:16

But not that big of a deal, especially not in something that we're just like, 2:21

[NOISE] let's see what we can build. 2:23

Feel free to experiment and see if you can make it not do that. 2:25

But let's see, so four, three, two, one. 2:28

Our timer's done, cool. 2:33

So, yeah, you can see it's about a second early, 2:36

it fires off, but not that big of a deal. 2:39

So, there you go. 2:42

In just a few short videos, and I don't know, 100 lines of code? 2:43

Let's see, how many lines did we add here? 2:49

114! 2:52

114 lines of code, a few short videos, we have built a fully function Pymodoro 2:54

application that'll let us do a lot of work very, very quickly. 2:58

While our little app might not do much, it gives us a good glimpse of what all we can 3:04

do with the Kintor and the rest of Python. 3:08

Whether you're building your whole app into Kintor or just using it at a proof 3:10

of concept, I think this library will serve you well in the future. 3:13

I know people making games in it, and even using TkIntor to control lasers. 3:17

I can't wait to see what you do with it. 3:20

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