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G'day everyone, welcome back again.
Our app's coming along, and we've got a working ViewModel,

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and an adapter that provides data to the RecyclerView.

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Next, we'll make the edit and delete buttons do something.

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We'll start by getting them to display a
message in the log.

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The principle is quite simple.
They're just buttons,

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so we need to give them an onClick function,
to execute whenever the user taps them.

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What we have to decide is where that onClick function should live,

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and what should happen when the buttons are clicked.

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So in this video, we'll set up the onClickListeners for our buttons.

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In the next video, we'll review callback functions

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and why we need to create an interface,
before getting the buttons to actually do something useful.

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Let's have a look at the onBindViewHolder function

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in the CursorRecyclerViewAdapter class.

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If the TODO comments that were added haven't given this away, here's an obvious place to start.

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This is where we create the views for each row of the RecyclerAdapter,

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so we already have references to the buttons.

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We could set our onClickListeners for the buttons in this onBindViewHolder function,

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just like you set the listeners in an activity's onCreate,
for example.

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Another approach, and the one we're going to use here,
is to give our view holder a bind function.

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All this code is part of binding the data to the view,
and bind is an obvious name for the function.

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We'll pass in the task, because ultimately
we'll want to provide the task details

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to whatever is listening for the buttons
to be tapped.

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Let's add the bind function.

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We'll set our values, and make sure the buttons are visible.

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Let's add the listeners.

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We're going to respond to long clicks a bit later,

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so I've added an onLongClickListener as well.

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The onLongClickListener has to return true
if it has handled the tap,

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and that's the result of the lambda on line 37.

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The task needs to be available to our callback functions,
because the activity, or fragment, that we callback

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will need to know which task we
want to edit or delete.

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That's why we've passed it as the
argument to the bind function.

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If we're gonna pass the task in here,
it also makes sense to bind the task details to the widgets.

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That's what we're doing with the first bit of code.

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That means we don't need to set the data in onBindViewHolder.

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We need to replace these lines

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with the call to bind.

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That should work.
Let's run it and check the logcat to see what we've got.

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Remember to clear any filter in the textbox.

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That should be easy to do,
but there's currently a bug in Android Studio.

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You may find that the top toolbar for the logcat disappears.

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At the moment, a fix for that is to click in the event log tab
in the bottom right.

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That displays the event log, and clicking it again removes the event log
and puts back the logcat's toolbar.

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I'll demonstrate that if my toolbar disappears,
but it looks like it hasn't.

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All right, each time I tap a button in the emulator
we get an entry in the log cat.

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So it's working fine. A long tap on the task also works.

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We've got our buttons responding to taps,
and we know which tasks the taps refer to.

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I'll stop this video here.

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In the next video, we'll get the buttons to do something more useful. See you in the next one.