OHMAE Ryosuke
Development Division 1, Media Services Group, Media Group, Yahoo! JAPAN
Initiatives to Improve Code
Integrity to Continue Providing
New Value
- Yahoo! JAPAN Weather App -
Slide 2
Slide 2 text
Self-introduction
OHMAE Ryosuke
https://github.com/ohmae
Twitter: ryo_mm2d
Qiita: ryo_mm2d
Yahoo! JAPAN @Osaka
Android App Engineer
Yahoo! JAPAN Weather App
Slide 3
Slide 3 text
Initiatives to Improve Code
Integrity to Continue Providing
New Value
Slide 4
Slide 4 text
Continue providing new value
Improve Code Integrity
Development of new feature
New value
Slide 5
Slide 5 text
写真：アフロ
Yahoo! JAPAN Weather App
Slide 6
Slide 6 text
Changes in Yahoo! JAPAN weather app
2019 2022
Slide 7
Slide 7 text
Do ordinary things
as a matter of course
Slide 8
Slide 8 text
Agenda
Specification
s and design
Framework and
code design
App lifespan
Slide 9
Slide 9 text
Agenda
Specification
s and design
Framework and
code design
App lifespan
Straightforward use of
standard components
Maintenance costs Convenience
Accessibility Completeness
Slide 25
Slide 25 text
An Android app
should be like an Android app
Slide 26
Slide 26 text
Specification
and design
OS compatibility
vs
Slide 27
Slide 27 text
Specification
and design
OS compatibility
+
Slide 28
Slide 28 text
Healthy
specifications
and design
lAssertively introducing design guidelines
and libraries and learning how to use them
appropriately
lAchieving a high level of completeness
with straightforward implementation and
strong OS compatibility
lWe share specification and design intent,
and our engineers propose specifications
with strong OS compatibility
Slide 29
Slide 29 text
Agenda
Specification
s and design
Framework and
code design
App lifespan
Slide 30
Slide 30 text
Lifecycle and
threads
Single package
Wide range of
support
Difficulties in Android app development
Slide 31
Slide 31 text
Technical debt has an overall effect
l Wrong abstruction / commonization
l BaseActivity
l BaseFragment
Proper scoping is essential
Implementing everything in a single package
写真：アフロ
Slide 32
Slide 32 text
Lifecycle and threads
Understand the lifecycle and treat it appropriately
Rotating the screen regenerates the instance
Status handover
Callback reconnection
Handle threads properly
Only the main thread can control the UI
No network access allowed on the main thread
onCreate()
onStart()
onResume()
onPause()
onStop()
onDestroy()
Activity launched
Activity running
Activity shutdown
Slide 33
Slide 33 text
Wide range of support
Android 13 API 33
Android 12L API 32
Android 12 API 31
Android 11 API 30
Android 10 API 29
Android 9 API 28
Android 8.1 API 27
Android 8 API 26
Android 7.1 API 25
Android 7 API 24
Slide 34
Slide 34 text
Use what is available
+
Fit into the mold
Slide 35
Slide 35 text
Use what is available
Actively introduce existing systems such as OSS and maintain a modern development environment
RxJava
Kotlin
RxKotlin
Retrofit
OkHttp
Room
ViewModel
LiveData
Jetpack
Material components
Lottie
Firebase
Slide 36
Slide 36 text
Kotlin
lGoogle I/O 2017 Official support
lGoogle I/O 2019 Kotlin-first
lSecure code
lDistinguishes Nullable/NonNull
lExpressive and concise description
lExtensive standard library
Slide 37
Slide 37 text
Fit into the mold
Architecture
Slide 38
Slide 38 text
Architecture
l Strategies for how to organize modules
l We don't have to think about them
each time
l Can be made by imitation
lLimits the scope naturally
l Does not fall into local optimums
Slide 39
Slide 39 text
Work hard and have fun
or
Have fun and work hard
Slide 40
Slide 40 text
Use what is
available
+
Fit into the
mold
lAvoid to do difficult things
lTotal optimum instead of local optimum
lSparing no effort to make things easy
lAdding up lots of "betters" instead of a
one-time "best"
Slide 41
Slide 41 text
Agenda
Framework and
code design
Specification
s and design
App lifespan
Slide 42
Slide 42 text
"QQMJGFTQBO
2022
2010
First release Now
,FFQVQEBUJOHUIFTBNF
QBDLBHFGPSZFBSTPSNPSF
*UJTOPUJNQPTTJCMFUPNJHSBUFCZDSFBUJOHBDPNQMFUFMZTFQBSBUFBQQMJDBUJPO
:PVIBWFUPCFEFUFSNJOFEFOPVHI
Slide 43
Slide 43 text
App lifespan
Invisible
specifications
Irreversible
elements
Users who do
not update
Slide 44
Slide 44 text
Irreversible
elements
lExternal protocol
lAndroidManifest
lPersistence information
App specifications that have gone outside the app
Slide 45
Slide 45 text
Invisible
specifications
lCoordination information
lCustom scheme
lInter-process communication
lPast persistence information
App specifications that have gone outside the app
Slide 46
Slide 46 text
App specifications placed outside the app
continue to affect the app even if the process
disappears from the app
Slide 47
Slide 47 text
Users who
do not
update
lOutdated information remains in the
market
lSupport cannot be easily cut off
The problem becomes more complex
Slide 48
Slide 48 text
Just looking at it
does not make the code healthy
Slide 49
Slide 49 text
Sorting out
puzzling
specifications
lIs it being used?
lEstablishment of overall consistency
lAwareness of the end
Past
Slide 50
Slide 50 text
Gradually
suppressing
the impact
lSupport for both & penetration of migration
processing
lAllowing for temporary waste
lEnd of support
lSupport limit： 2 years
Current
Slide 51
Slide 51 text
Do not bring
external
specification
s inside
lExternal specifications are absorbed in the
outer-most portion of the application
lSeparate from internal specifications
lArchitecture
Current
Slide 52
Slide 52 text
Specifications
that do not
result in future
technical debt
l Preparing for migration
l What we are making now will definitely become
obsolete someday
l Proposing specifications that do not
leave debts to the future
l Will anyone in the future be able to maintain it?
Future
Slide 53
Slide 53 text
To maintain
code health
l Identifying unnecessary specification
l Tenacious migration over a long span of
time
l Looking to the future and considering
specifications that will not cause technical
debt
Slide 54
Slide 54 text
Summary
Specifications and design
Proposing healthy specifications to maintain healthy code
Framework and code design
Sparing no effort to make things easy
App lifespan
Clean the slate and create specifications that do not cause future debt