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Alright so there's another interesting option on the attributes pane for image views, and that's adjust

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view bounds.

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So I'm going to make sure that image view's selected over here, and you can see over here we've got adjust view bounds.

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Now I'm going to leave that set to false to start with,

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and we're going to change it later so that we can see the effect.

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But if we want to see what it does, or found out more about what it does, I'm just going to go into Google in a

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browser.

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We'll do a search for image view dot adjust view bounds. You can see that's the first option there, and then we want to click

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on the first option which is the widget image view page on developer dot android dot com. And this is obviously

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Google's documentation and it's an excellent place to start.

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Now this page is the documentation for the image view widget. So it describes all the methods and properties

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you can use with an image view.

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And you can actually use control f to search for adjust view bounds on the page, and if I do that myself on the Mac with

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command f, adjust view bounds, and you can see in the top right hand corner,

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we've got 21 matches there.

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Now we set this to true,

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if we want the image view to adjust its bounds, to preserve the aspect ratio of its drawable.

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Now it's drawable, remember, is the image that it contains.

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Now this seems a bit odd.

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We've told the image view to scale its drawable, to fit the image view, but now we're also telling the image view to

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alter its size to fit the drawable.

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Well it's actually a two step process.

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The image will be scaled to fit, then the image view will resize itself,

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so there's no space around the image on either side.

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Now if you're struggling to understand that, it'll make sense once you see it in action.

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Now if we have look at this set adjust view bounds, set adjust view bounds, but there are 20 other references

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on this page so it's well worth checking out everything

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that the documentation has to say about something, rather than just settling on the first thing you

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read.

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So I'm going to flick on through some of the other references.

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I'm not going to spend time reading each one though because the video will go on forever.

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But I'll just forward and start looking at some of these matches.

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This one here is the one that I particularly want you to see, and it was actually the 12th match.

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Now this note here is quite interesting, especially if you're targeting API 17.

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So the image view doesn't always grow to fill the available space when you're using adjust view bounds.

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That's expected behavior,

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and we don't have to spend days working out why. Reading the documentation doesn't just mean glancing at

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the first couple of paragraphs.

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It's well worth spending the time to read it thoroughly,

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if you've gone to the trouble of searching for it in the first place. And it can save you a lot of time

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trying to sort out problems, when things don't work as you might expect. Now here you could've wasted

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a lot of time, trying to debug something that isn't a bug.

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Well arguably it is,

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but once a bugs documented of course, it becomes a feature.

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So it looks like I should probably set adjust view bounds to true here, but if I go back to Android

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Studio now, we would normally do that by clicking on this little try state button, and that lets us choose

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from true when it's clicked, when it's ticked rather. So that's true now,

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false when isn't.

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So that would be false, and whatever the default setting is when it's got a dash through it, which

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it was originally set to.

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So I'm going to leave it set to the default though, so that we can switch it on later and see what effect it has.

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And that's better than just trying to imagine it.

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So something that's not obvious though is that the blueprint's showing us how much height our layout row's

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taking up on the screen.

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Now the solid outline running to the bottom of the layout is indicating that our widgets will display at the full

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height of the screen.

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Now that's important because the recycler view will be trying to fit as many of these layouts on the

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screen as possible, to give a scrollable list.

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Now something's causing that,

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and as the text in the text view is just the word text view, it's unlikely to be that.

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So let's have a look at the image view.

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So making sure that you've selected that, and its layout height's set to match underscore parent, which

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we set it to, which means it'll be as high as possible.

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Now if I change that back to wrap underscore content, it shrinks to a more reasonable size.

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The outline though is still filling the screen though, which isn't what we want.

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Now if the outline still extends all the way to the bottom of the screen, that indicates that the linear

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layout's layout underscore height is set to match underscore parent.

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And that can mess up the display when you use it in something like a list view or recycler view.

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So in other words what we want to do here is make sure our layout underscore height, select the layout, I want to make sure

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the layout underscore height is in fact set to wrap content.

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So I'm going to do that, and you can see when I did that the outline shrunk.

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And if I go back and click on match underscore parent again, you can see that it expands, so I want to set it back to to wrap

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underscore content here.

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Now it doesn't always show in the designer, but this is where the blueprint's incredibly useful, because

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it always shows things like that.

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Now although it wouldn't have been the end of the world if we'd missed it, we'd have to have come back and change

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the layout after running the app, to make it look right.

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Alright so we're good to go at this point.

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So I'm going to go back into text, the text tab, and reformat the code.

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Back to design, and I'll finish the video here. In the next one,

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we're going to continue to create the other layouts for the app. So I'll see you in the next video.