Check out how developing for Android changed since Material Design is out!

1. Michał Biernacki, DeSmart
Android app materialization in practice

2. ?
Material Design from developer’s
perspective

3. Material Design - dev's perspective
App layout changes,
a lot of new APIs making view transitions
and animations Activity easier...
… to apply on Lollipop only,
possibility to set z-index to views so that
framework could render real time shadows ...
… and for the remaining 99% of the devices
we will make them as graphics.

4. Fragmentation FTW!!!

5. Where to start
?

6. Styles

7. Styles
For Android 5.0+:
Material.Light
Material.Dark
For AppCompat:
Theme.AppCompat.Light
ThemeAppCompat.Dark

8. Styles
android:colorPrimary
android:colorPrimaryDark
android:colorAccent
android:statusBarColor (inherited by default
from colorPrimaryDark)
when using AppCompat write attributes without
android namespace.

9. Views/Widgets

10. Toolbar

11. Toolbar
ActionBar class generalization,
it can be placed at any level of view hierarchy,
you can have multiple Toolbar instances
in your layout,
you can set Toolbar as a replacement
for standard ActionBar in your Activity.

12. Toolbar as ActionBar (in AppCompat)
Set the correct style so that the framework
won't draw standard ActionBar (using
Theme.AppCompat.NoActionBar for example),
add Toolbar to your layout,
make your Activity extend ActionBarActivity,
and in your Activity:
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);

13. Toolbar
You can add child components to the Toolbar
which inherits from ViewGroup,
Toolbar containing a SwitchCompat
in Google Inbox app:

14. SwitchCompat - bug

15. RecyclerView

16. RecyclerView
ListView 2.0,
RecyclerView is a flexible view providing
a limited window into a large data set,
it uses plugable classes for drawing, animating
and positioning child components,
it’s available as a separate library
com.android.support:recyclerview-v7

17. RecyclerView - Adapter, ViewHolder
Provides access to data layer,
creates layout for each element and fills it with data,
RecyclerView uses new interface for Adapter
called RecyclerView.Adapter…
…so say bye bye to CursorAdapter, ArrayAdapter
etc.
it uses convertView and holder pattern by default.

18. RecyclerView - LayoutManager
Responsible for measuring and positioning
elements in RecyclerView,
responsible for cleaning views from memory
which are no longer visible to the users,
application will throw exception if we don’t set
LayoutManager for RecyclerView,
Google provides two standard implementations
for this class: LinearLayoutManager
and GridLayoutManager.

19. RecyclerView - ItemDecoration
Simple class responsible for additional view
decorations,
it’s optional to use it,
you can add a couple of decorations
to one RecyclerView,
all decorations are drawn in the same order
as they've been added using onDraw()
and onDrawOver() methods.

20. RecyclerView - ItemAnimator
Class which animates collection elements,
animates elements while adding / deleting them
from collection and when element movement
is required,
if we don’t prepare our custom ItemAnimator the
Recycler will use default implementation.

21. RecyclerView - ItemAnimator
notifyDataSetChanged()
Instead of it we use:
notifyItemInserted(int position);
notifyItemRemoved(int position);
notifyDataSetChanged() is bleah!

22. RecyclerView - Summary
We put RecyclerView to the layout,
we get its references in our Activity or Fragment,
we attach LayoutManager,
we attach adapter with data,
we add as many ItemDecorators as we need,
if we need our own animations we add our custom
ItemAnimator.

23. CardView

24. CardView
ViewGroup with predefined „card” background,
allows to set elevation on each system version,
this class is available as a separate library
com.android.support:cardview-v7

25. CardView

26. Other

27. Palette
Picks colors from given bitmap,
there are two methods to pick the colors:
public static generate(Bitmap)
public static generateAsync(Bitmap)
Class tries to assign colors as Vibrant or Muted.

28. Z-Index/Elevation
ViewCompat.setElevation(View, float),
method above helps us avoid checking at runtime
OS versions the app works on,
shadows will be rendered only for Android 5.0.

29. Activity transitions
API 21 makes it easy to animate elements
from one Activity to another,
it’s also possible to set unshared elements
enter and exit animations.

31. Activity transitions
In styles android:windowContentTransitions true
we specify animations in xml,
we set enter and exit animations for shared
elements in xml or in code,
we set attribute “transitionName” on the element we
want to animate,
we use method
ActivityOptions.makeSceneTransitionAnimation(Con
text, View, String);

33. CircularReveal
Animator anim =
ViewAnimationUtils.createCircularReveal(view, x, y,
0, radius);
myView.setVisibility(View.VISIBLE);
anim.start();

34. That’s all folks!
mail: hellboy@desmart.com
www: www.desmart.com
blog: www.desmart.com/blog