Android tips.

1. 10 Commandments for Better Android
Development
Trey Robinson

2. Thou shalt pick a reasonable min sdk version.
(9 is not reasonable)
(14 isn’t either)

3. Choosing a Min SDK

4. Choosing a Min SDK
● Froyo + Gingerbread + ICS = 8.7%
● Users with older OS versions download
fewer applications.
● Newer features and better phones often
mean faster time to market with a better
product.

5. So my Min SDK should be….
19(Seriously)
(If you must go lower.. 16)

6. Thou shalt not write boilerplate code.
(Ain’t nobody got time for that)

7. ● View inflation
● OnClick, OnItemSelected.. etc etc
● Saving state
● Parcelables
Things you should understand..

8. Never write them again...
Old WayNew Way

9. And OnClicks...

10. Icepick and Saving State..

11. Parcelables

12. Automatic Parcelables
● Parcelable Plugin
○ https://github.com/mcharmas/android-parcelable-intellij-plugin
● Auto Parcel
○ https://github.com/frankiesardo/auto-parcel
● Parceler
○ https://github.com/johncarl81/parceler

13. Know thy IDE
You companion on the path to speed and
agility

14. ● Control + R
● Control + D
● ⌘ + Shift + O
● ⌘ + Shift + Up/Down
● ⌘ + Option + Up/Down
● ⌘ + Shift + f
Useful Hotkeys

15. Live Templates
(Demo)

16. https://github.com/keyboardsurfer/idea-live-templates
MORE LIVE TEMPLATES

17. Thou shalt not consume REST APIs with
AsyncTasks
(Unless you are a masochist)

18. Retrofit vs Volley vs AsyncTask

19. Thou shalt read Effective
Java.

20. Some useful stuff..
● Factory vs Constructors
● Builders
● Singletons
● equals and hashCode
● toString
● Class accessibility
● Mutability
● Composition vs Inheritance
● Interfaces vs Abstract Classes
● Generics
● Lists vs Arrays
● Enum vs int constants
● Overloading
● Javadoc
● loops
● String concatenation
● Exceptions
● Concurrency

21. Thou shalt not ask permission when an
Intent will do.
(or how to avoid upsetting your users)

22. <uses-permission android:name="android.permission.SEND_SMS" />
Example: Sending an SMS
Option One:
Option Two:
Intent sendIntent = new Intent(Intent.ACTION_VIEW);
sendIntent.setData(Uri.parse("sms:" + telephoneNumber));
sendIntent.putExtra("sms_body", x);
startActivity(sendIntent);

23. Thou shalt understand
your builds.
(and make them faster and more useful)

24. ● Manifest Mergers
● A little bit of Groovy
● Sweet debug settings
Things to Learn

25. For example..
<application android:vmSafeMode="true">
Added to the manifest in debug/src/AndroidManifest.xml

26. Environment Variables
buildTypes {
debug {
buildConfigField "String", "BASE_URL", ""https://myserver-dev.herokuapp.com";"
}
qa {
buildConfigField "String", "BASE_URL", ""https://myserver-qa.herokuapp.com";"
signingConfig signingConfigs.debug
}
support {
buildConfigField "String", "BASE_URL", ""https://myserver-support.herokuapp.com";"
signingConfig signingConfigs.debug
}
release {
minifyEnabled true
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-project.txt'
buildConfigField "String", "BASE_URL", ""https://www.myserver.com";"
}
}

27. (a what?)
Thou shalt use an activity
alias for your launcher

28. <activity android:name=".Launcher" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
Like so..
<activity-alias
android:name=".Launcher"
android:targetActivity=".ui.MyNewLauncher" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity-alias>
<activity android:name=".ui.MyNewLauncher" />

29. Thou shalt stand on the
shoulders of giants.
(Or how to increase your knowledge in 3
easy steps.)

30. 1. Attend meetups! (DONE)
2. Leverage cool libraries and techniques for
fun and profit.
3. Follow people on twitter.
So Easy...

31. Cool Libraries
● RXJava
● Dagger / Dagger 2
● Picasso / Universal Image Loader / Glide
● Design Support Library
● Pocket Knife
● Realm
● Stetho

32. Twitter Follows
● Jake Wharton @JakeWharton
● Dan Lew @danlew42
● Chet Haase @chethaase
● And many many many more...
https://twitter.com/rdrobinson3/lists/android

33. THE END