Anko Uncensored4:26 with Ben Deitch
In this video we walk through our counter app to see what Anko's up to behind the scenes!
Okay, so now that we've got a fuzzy understanding of how this all works, 0:00 let's take a step back and see if we can make things a little bit clearer. 0:04 Here we are in main activity where our code that creates the layout. 0:08 It starts with a call to the relative layout, 0:12 which is an extension function on activity. 0:14 And, actually, that's all this code is, just one big function call 0:17 to relative layout, with one parameter that happens to be another function. 0:22 So inside a relative layout function, this passed in function will be the init 0:26 parameter, then all we have to do is, return the result of calling ankoView 0:31 with the relative layout constant and our init function. 0:36 And, remember, the relativeLayout constant is just a simple function 0:40 that takes on a context and returns an instance of underscore relatively layout. 0:43 From here, we call the ankoView method and 0:48 pass along our init function along with our underscore relativeLayout constant. 0:51 And note that we're calling the version which is an extension function 0:55 on the activity class. 0:58 So inside this function this keyword will be an activity. 1:00 Moving on to the end side of the function, 1:05 we start by creating a variable to hold the context. 1:07 Then we pass this context to our factory to give us an instance of 1:10 underscore relative layout. 1:14 Next, we call our init function on our new layout, 1:15 which brings us to the inside of our init function. 1:19 Inside the init function, 1:22 we start with the call to text view, which is an extension function on View Manager. 1:24 But, don't worry, I looked into it and View Manager is an interface that gets 1:29 implemented by relative layout, so we're good. 1:33 Next, just like with our relative well function, we're passing in another 1:36 function to our text view function, and it gets passed in as the init parameter. 1:40 Now we're calling anko view again, but this time with the text view constant and 1:45 a different init parameter. 1:50 So let's pass those in, and also, 1:51 note that this time we're calling the View Manager version of ankoView. 1:54 So this key word will be our view manager, AKA, our relative layout. 1:59 Back inside the ankoView function, we grab a context and 2:04 use it alongside our factory function to create a text view. 2:08 Then, we call in it on our text view and it sets our text view ID to 11, 2:11 its text to 0, and its text size to 24. 2:16 Once that's done, 2:21 we're back in our ankoView function where we add our TextView to a relative layout. 2:22 Then, we return our TextView, and 2:27 return it again, and then it get sets to our counter TextView variable. 2:29 After that, 2:34 we march on to the button function where we again pass in another function. 2:35 Just like last time, we end up calling ankoView within an init function and 2:40 a view factory, but this time it's a different init function, 2:44 and the view factory returns buttons. 2:47 So inside ankoView, we grab our context, create a button using that context, and 2:50 then initialize that button with our init function, 2:55 which adds on clicklistener to our button. 2:58 Back in ankoView, we then add our button to a relative layout, 3:00 and then return our button, and return it again. 3:04 But this time, instead of setting some variable equal to our button we 3:08 immediately call the lparams function on our button, and 3:12 again, we pass in another function. 3:15 Inside the lparams function, we start by creating a relative layout, 3:18 layout params object. 3:22 Then, we call our init function where we modify the layout params 3:24 to say that this view, our button, should be below our text view. 3:28 Then we set our buttons layout param to our newly created and 3:32 initialized layout parameters. 3:36 And, finally, we return our button, 3:39 which brings us to the end of our relative layouts init function. 3:41 And once that's done, we're back at the activities ankoView function where we 3:45 add our relative layout for our activity, and then return our relative layout. 3:49 Then we return it one more time, which brings us back to the end of our layout. 3:54 That was a lot, but on the plus side, now we've got an excellent understanding 3:59 of how Anko works, and trust me, this will make the rest of the course a lot easier. 4:04 Speaking of the rest of the course, 4:10 it's about time that we get back to our solitaire game. 4:12 I mean, it's pretty cool that we can see the game in our debug log, but 4:14 what good is a game if you can't play it? 4:18 So, from here on out we'll be focused on using what we just learned 4:20 to implement the UI for our game. 4:24
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