AndroidApp to the challenge

Udi Cohen

We'll talk about..● Graphics:

– Over Draw

– Detect UI glitches

– Optimizing layouts with HierarchyViewer

● Profiling with Traceview● Helping the GC with HPROF● Playing tough with StrictMode● Getting intimate with the OS using EventLog● Hardware Accelerate your app● Tips

whoami

Over Draw● Draw something on top of

something else● Rule – aim overdraw to 2x● Could indicate a complex

hierarchy● “Show GPU overdraws” on

Developer options (4.2+)

4x

3x

2x

1x

Over Draw – Solutions

● Remove default background● getWindow().setBackgroundDrawable(null)

● <item name="android:windowBackground">@null</item>

● Transparent regions in 9patches

● Use tools● Tracer for OpenGL

● Hierarchy Viewer

Over DrawHappens to the best of us

Tracer for OpenGL

● Layout tree step by step● See redundant draw operations● Heavy

Dumpsys gfxinfo

● Since Jelly Bean● Last 128 frames● Frame < 16ms● 3 columns

– Draw

– Process

– Execute

●

113

2537

4961

7385

975

9 1721 29

33 4145 53

57 6569 77

81 8993 101

105109

113117

121125

0

1

2

3

4

5

6

7

8

9

Execute

Process

Draw

Hierarchy Viewer

Traceview Profiling

● Performance of each method● Graphical interface● Run from DDMS or code

Traceview Profiling

Traceview Profiling

Inclusive: Includes child functions

Exclusive: This function only

Traceview Profiling

Traceview Profiling

So...what's the problem here?

Helping out the GC

● Allocation Tracker (DDMS)●

Helping out the GC

● Memory profiling → Dalvik HPROF file

Use code or DDMS ● Use hprof-conv to convert to standard● Use any Java HPROF analyzer

Helping out the GC

● Eclipse MAT (Memory Analyzer Tool)

Helping out the GC

● Histogram & Dominator tree

Tips - Bitmaps

● InJustDecodeBounds – Load only properties

● InBitmap – reuse other allocation● InSampleSize – good for preview● Resource folders

StrictMode

● Problems Detector● Single thread or the entire VM● Show dialog, write to Log and more..● Usually used to detect slow operations on

UI thread● Came with Gingerbread (2.3)

Log

● EventLog– Adb logcat -b events

– Framework level logs

– DB and system operations

Hardware Acceleration

● android:hardwareAccelerated="true"ortargetApi >= 14

● Efficient drawing model● Compatibility issues

– Custom views

– Unsupported operations

Hardware Acceleration

● Good for animations● View Layers

Tips● Always Measure● Lint

– Comes with the SDK

– Scan the project's for optimizations

– Great Eclipse/IntelliJ integration

● ListView – Easy on the getView()● Alpha – Watch it...● Storage Read/Write● Direct access inside the class (!Get/Set)● SQLite indexes

Thank you

@udinic

http://www.udinic.com

udi@udinic.com