This document discusses adding multi-screen support to Android applications using the Presentation API. It describes various connection methods like Miracast, HDMI, and Chromecast Mirroring. It provides examples of using the Presentation API to display content on an external screen independently of the phone screen. It also gives ideas for dual-screen applications and discusses related APIs.

1. Adding multi-screen support to Android* Applicationsusing the Presentation API
Xavier Hallade, Developer Evangelist, Intel Corporation
ph0b.com -@ph0b

2. 2
Android Multi-Screen support
Miracast
ChromecastMirroring
Micro-HDMI
MHL/Slimport
Wireless
Yes
Yes
No
No
Charges your device
No
No
No
Yes
Requiresexisting WiFi
No
Yes
No
No
Directcommunication
Yes
Yes (withTDLS)
Yes
Yes
Latency
Low-Med
Medium
None
None
Number of Supported devices
Most Android4.2+ devices
13, more coming
?
?
Since version 4.2, Android supports the Presentation API that allows developers to manipulate the content displayed on additional screens.

3. 3
Connecting a screen to your device
Chromecast Mirroring
Miracast
Developer Settings

4. 4
Clone Mode (Default)
After establishing the connection, user sees local screen on the remote display
Resolution sent to remote is the same as local display’s
No need to do anything to support this mode

5. 5
Extended Video Mode(Intel®Platform Specific)
Video mode is activated automatically when user plays a video using Android* Media Player framework (ex: VideoView)
User sees video content on the remote at the 1080p resolution (or whatever the native resolution of the content is)
Local video rendering is turned off to save power, but UI stays untouched

6. 6
Dual Screen Display With Single App
Remote screen used for content viewing
Local screen used for control & context info
Application can target this mode using the Android*Presentation API

7. 7
Dual Screen Display With Background Service
User can navigate out of the app and play 1080p video on local screen or use any other application, including receiving a phone call without any disruption to background playback

8. 8
Connecting a Wireless Display on Android*
Sony* XperiaZ
Stock/Intel®
Samsung* Galaxy S4

9. 9
Miracast* Concept
Video Render
Audio Render
VideoDecode
AudioDecode
De-Packetize
De-Packetize
Link Content Protection Decrypt (Optional)
AV DeMux
Transport
LLC
WI-FiMAC (Direct Link)
Wi-Fi PHY
SINK
VideoEncode
AudioEncode
Packetize
Packetize
Link Content Protection Encrypt (Optional)
AV Mux
Transport
LLC
WI-FiMAC (Direct Link)
Wi-Fi PHY
Video Frames
Audio Samples
SOURCE

10. 10
Adapters
•Actiontec*ScreenBeamPro
•Actiontec*ScreenBeamMini 2
•Netgear*(ex: PTV3000)
•Viewsonic(WPG-370)
•Best Buy*Rocketfish*
•Lenovo*
•…
Projectors
•Dell*
•Seiko Epson *
•Ricoh*
•LG*
•…
TVs
•Samsung*
•Toshiba*
•LG*
•TCL*
•Sharp*
•Philips*
•…
Miracast*Certified Sink Devices
Full list of Miracast* certified devices can be found at
http://www.wi-fi.org/wi-fi-certified-miracast
Intel®WiDi Certified
MiBox

11. 11
Second-Screen Enabled Devices running Android* 4.2.x
Device
Miracast* Certified
HDMI*, MHL* or SlimPort*
Samsung* Galaxy S4
Yes
Yes
Samsung Galaxy Tab3 10.1
No
Yes
Sony* XperiaZ
Yes
Yes
LG* OptimusG
Yes
Yes
Nexus* 4, 5, 7 (2013)
Yes
Yes
HTC* One
Yes
Yes
… Most Android 4.2+ devices
Yes

12. 12
Android* Secondary Display API
Android added Second-Screen support via the Presentation class in Android* 4.2 (API Level 17), allowing you to:
Implement support for a second screen in your applications without having to worry about the way the displays are connected (Display agnostic)
Works with MHL*, HDMI*, SlimPort*, Miracast* & Chromecast Mirroring* compatible devices
You can control the output on the remote (second) screen independently of the phone screen

13. 13
The Presentation Object
Dialog
Presentation
You need to have a fragment based navigation if you want to keep it running while navigating in the app.
The activity should take care of pausing and resuming whatever content is playing within the presentation whenever the activity itself is paused or resumed.
•Presentation is the based class and should be extended:
•Presentation inherits from Dialog, and as for a Dialog its lifecycle is bound to an Activity
public class DemoPresentation extendsPresentation {
•Needs to be associated with a Display at creation time

14. 14
Using the Presentation API
Before showing a Presentation you need to select a Display, this can be done in 2 ways:
1.MediaRouterAPI (in API 16): system will decide the best display for you!
also available in the Support Library v7*
2.Display Manager API (in API 17): Enumeration of displays
// Get the MediaRouterservice
MediaRouter mMediaRouter= (MediaRouter)getSystemService(Context.MEDIA_ROUTER_SERVICE);
// Care only about routes that have full video support.
MediaRouter.RouteInfomRouteInfo = mMediaRouter.getSelectedRoute(MediaRouter.ROUTE_TYPE_LIVE_VIDEO);
Display presentationDisplay= mRouteInfo.getPresentationDisplay();
// Get the DisplayManagerservice.
DisplayManagermDisplayManager= (DisplayManager)getSystemService(Context.DISPLAY_SERVICE);
// enumerate the displays
Display[] presentationDisplays= mDisplayManager.getDisplays(DisplayManager.DISPLAY_CATEGORY_PRESENTATION);

15. 15
Presentation API
MediaRouter. getSelectedRoute(ROUTE_TYPE_LIVE_VIDEO)
MediaRouter. routeInfo
getPresentationDisplay()
new Presentation(activityContext, display)
.show()
Then, using MediaRouter.addCallback, you have to monitor:
•onRouteUnselected
•onRouteSelected
•onRoutePresentationDisplayChanged
How to get a Presentation displayed:
And inside the activity owning the Presentation:
•onResume
•onPause

16. 16
Designing Layout for the Presentation
Use a layout the same way as with a Dialog.
Display properties are the same than with Google*TV:
TV display is as bigger from a phone than the user sits further from a phone: screen density is comparable.
Default theme is HoloDark: light text on dark background is easier to read on TV.
Orientation is always… landscape!
TV setting
Addressable screen size
Density Identifier
Screen Density
Display Resolution
Screen size identifier
720p
1280 x 720 px
tvdpi
213 dp
960 x 540 dp
large
1080p
1920 x 1080 px
xhdpi
320 dp
960 x 540 dp
large
source: https://developers.google.com/tv/android/docs/gtv_android_patterns

17. 17
Second-ScreenDemo

18. 18
Intel®WiDi –Dual Screen Possibilities 97 MPH 4 POS107 MPH 8 POS111 MPH 14 POSLIVE FEEDTURN 7
App Window #1
Configure and add select content
on 2’ screen
App Window #2
View multi-angle
Videos & more on
10’ large screen
Multi-video
User configured
Application
EXTREME
Content
Driver #48-Car Cam
Driver #10 –
Fol ow the Car
Track Cam
Location
Car Race Main Live Feed
Driver#8-Car Cam
Driver#99-Car Cam
Tweet Feeds….
Layout 1
Layout 4
Layout 3
Layout 2
MPH / POS
MPH / POS
MPH //POS
Clear All
Follow Driver
Driver
Tweets
Driver Stats
Live Feed
Driver
Location
Load Layout
Save Layout
THERACE
One application, pulling content from one site, driving two screens!

19. 19
Ideas for Dual Screen Applications
Enter search term
Touchpad Mode
Web Browser

20. 20
Ideas for Dual Screen Applications
And
Keyboard Input Mode
w
q
e
r
t
y
u
i
o
p
s
a
d
f
g
h
j
k
l
z

x
c
v
b
n
m
&123
/
space
·
search
And
Web Browser

21. 21
Ideas for Dual Screen Applications
Games
Dual Joysticks Mode

22. 22
Ideas for Dual Screen Applications
Productivity App

23. 23
Ideas for Dual Screen Applications
Current matches
X vs. Y
A vs. B
X vs. Z
Add Score
11
Player X vs. Player Z
7
Tournament Manager

24. 25
Wifi Display APIs -Android* 4.2/4.3
All of the below APIs are internal as of Android* 4.2/4.3
They are part of AOSP and publicly exposed, but not part of the framework so are not guaranteed to work
android.hardware.display.DisplayManager
…
String ACTION_WIFI_DISPLAY_STATUS_CHANGED
WifiDisplayStatusgetWifiDisplayStatus()
void scanWifiDisplays()
void connectWifiDisplay(StringdeviceAdress)¹
void disconnectWifiDisplay()²
void forgetWifiDisplay(Stringaddress)²
void renameWifiDisplay(String address,Stringalias)²
android.hardware.display.
WifiDisplayStatus
intgetFeatureState()
intgetScanState()
intgetActiveDisplayState()
WifiDisplaygetActiveDisplay()
WifiDisplay[] getAvailableDisplays()
WifiDisplay[] getRememberedDisplays()
android.hardware.display.WifiDisplay
StringgetDeviceAddress()
String getDeviceName()
String getDeviceAlias()
String getFriendlyDisplayName()
android.provider.Settings
…
String ACTION_WIFI_DISPLAY_SETTINGS
String getDeviceAlias()
String getFriendlyDisplayName()
¹android.permission.CONFIGURE_WIFI_DISPLAY required for unknown devices
²android.permission.CONFIGURE_WIFI_DISPLAY always required

25. 26
Adding a MediaRouteButton
In res/menu/default.xml: <item android:title="Media Route Settings" android:actionProviderClass="android.app.MediaRouteActionProvider" android:showAsAction="always" /> //Sets Media Route Button to second screen mode
mediaRouteActionProvider.setRouteTypes(MediaRouter.ROUTE_TYPE_LIVE_VIDEO);

26. 27
Some last comments
Presentation from background service:
•“Draw over apps” permission (SYSTEM_ALERT_WINDOW)
•TYPE_SYSTEM_ALERTLayoutParam.
USB Input Back Channel
HTML5 :
•standard: http://webscreens.github.io/presentation-api/
•Demo implementation in HexGLbuilt with crosswalk: https://github.com/hmin/HexGL
•documentation: https://github.com/crosswalk-project/crosswalk- website/wiki/presentation-api-manual

27. Q&A