Explains how to install Necessitas (Qt for Android), how to use it, and how to publish to the Android Market. Based on Necessitas 0.3 (3rd alpha) Slides are from Qt Developer Days 2011 in San Fransisco

1. Targeting Android with Qt
Espen Riskedal / cutehacks.com
@snowpong

2. Introduction
About me,
and about the talk.

3. About me
●
Trolltech and Nokia
●
Symbian and Windows CE
●
Co-founded cutehacks.com Espen Riskedal
@snowpong
●
Still believe in Qt Everywhere

4. We make apps

5. Purpose of this talk
“Teach you how to publish Qt
apps in the Android market”
I have a vested interest.

6. Agenda
●
Introduction
●
Qt on mobile platforms
●
Necessitas
●
Publishing to Android Market
●
Conclusion

7. 2.3.x “Gingerbread”
●
Google Nexus S
●
December 2010
●
Linux kernel 2.6.35
Photo: flickr.com/quinnanya/
CC / Some rights reserved

8. Qt on mobile platforms
A brief introduction on which
mobile platforms you can target
with Qt.

9. Today's mobile platforms

10. Supported by Qt

11. Almost supported by Qt

12. Some Android details
●
4 major releases
●
ARM and x86
●
Linux
●
Dalvik

13. Well known models
Galaxy S2 Tab 10.1 Xperia Play

14. Android API levels
Platform version API Level VERSION_CODE
... ... ...
Android 2.3 – 2.3.2 9 GINGERBREAD
... ... ...
Android 2.1.x 7 ECLAIR_MR
... ... ...
Android 1.5 3 CUPCAKE
... ... ...

15. Android platform distribution
http://developer.android.com/resources/dashboard/platform-versions.html

16. A possible future for Qt

17. Photo: flickr.com/quinnanya/
CC / Some rights reserved
1.6 “Donut”
●
Acer Liquid A1
●
September 2009
●
Linux kernel 2.6.29

18. Necessitas
Necessitas is a community port
of Qt for Android. Its founder
and main developer is BogDan
Vatra.

19. Installing Necessitas
●
OpenJDK (and Ant)
●
Necessitas 0.3 (3rd alpha)
http://bit.ly/qtand03
●
Linux
●
not root

20. Default values are OK

21. Included components
Android SDK
Android NDK
Qt, QtWebKit, QtMobility
Qt Creator
gdb / gdbserver
Ant
JDK

22. Adding an emulator

23. Getting a USB connection
●
Enable USB debugging
●
Settings->Applications->Development
●
Check connection
cd android-sdk/platform-tools
./adb devices
304D1...6203B05E device
???????????????? no permissions
●
Restart if needed
sudo ./adb kill-server
sudo ./adb devices

24. Install Ministro / Ministro 2

25. A “Hello Qt Quick” example
●
Qt Quick Project → Qt Quick Application
●
Name
●
Target (Android / armv5)
●
Next/Next/Next
●
Add QtDeclarative
●
Press Ctrl-R

26. Let's do it for real

27. Our “funky” main.qml
import QtQuick 1.0
Rectangle {
anchors.fill: parent
gradient: Gradient {
GradientStop { position: 0.0; color: "red" }
GradientStop { position: 0.33; color: "yellow" }
GradientStop { position: 1.0; color: "green" }
}
Rectangle {
id:ball;
width:100;
height:100;
radius: 50
color:"black"
Behavior on x { PropertyAnimation{ duration:500; easing.type: Easing.OutBounce} }
Behavior on y { PropertyAnimation{ duration:500; easing.type: Easing.OutBounce} }
}
MouseArea {
anchors.fill: parent
onClicked: {
ball.x=mouse.x
ball.y=mouse.y
}
}
}

28. Psychedelic bouncy ball

29. Added files explained
In addition to the .pro and .h/.cpp files:
android/AndroidManifest.xml
android/build.xml
android/res/*
android/src/.../ministro/*
android/src/.../origo/Qt*

30. How does it really work?

31. Necessitas status
●
SDK (almost) complete for
●
Windows, Linux and Mac
●
Qt Creator
●
Deploy libraries and app
●
Run app
●
Debug app
●
Signs the app

32. Popularity of Necessitas
●
~10000 downloads of 0.2.1 (2nd alpha)
●
~3200 downloads of 0.3 so far (3rd alpha)
●
~5000 views of my Münich slides

33. Necessitas roadmap
●
Alpha3 (just released!)
●
Lots of fixes
●
Signing for Android Market
●
OpenGL etc.
●
...
●
Alpha4
●
Android Style
●
Menu integration
●
...
●
Beta
●
Refactor Java wrapper code
●
Promise BIC
●
…?

34. Porting an actual app
Nokia N9 / Nokia 700
Samsung Galaxy S2

35. Changes needed
●
Use the right QML file and showFullScreen()
●
Hack around font issue
●
Add app icons
●
Set package name
●
Set minSdkVersion

36. QML and showFullScr...
--- a/main.cpp
+++ b/main.cpp
@@ -50,14 +56,16 @@ int main(int argc, char *argv[])
-#elif defined (Q_OS_SYMBIAN)
+#elif defined (Q_OS_ANDROID) || defined(Q_OS_SYMBIAN)
view.setSource(QUrl("qrc:/qml/Main.qml"));
view.showFullScreen();
#else

37. Font hack
--- a/main.cpp
+++ b/main.cpp
@@ -29,6 +29,12 @@ int main(int argc, char *argv[])
application.setOrganizationDomain("cutehacks.com");
application.setOrganizationName("Cutehacks");
+#if defined(Q_OS_ANDROID)
+ QFont boldFont = application.font();
+ boldFont.setBold(true);
+ application.setFont(boldFont);
+#endif

38. Setting app icons
commit a91fa2461ced0e75270b71c41ee80309e0697777
Author: Espen Riskedal <espen@cutehacks.com>
Date: Sun Oct 9 22:17:31 2011 +0200
added proper icons where it counts
android/res/drawable-hdpi/icon.png
android/res/drawable-ldpi/icon.png
android/res/drawable-mdpi/icon.png

39. Setting package name
--- a/android/AndroidManifest.xml
+++ b/android/AndroidManifest.xml
@@ -1,5 +1,5 @@
<?xml version='1.0' encoding='utf-8'?>
-<manifest package="eu.licentia.necessitas...
+<manifest package="com.cutehacks.fly" ...

40. Setting minSdkVersion
--- a/android/AndroidManifest.xml
+++ b/android/AndroidManifest.xml
@@ -14,4 +14,5 @@
<supports-screens android:largeScreens="t...
<uses-permission android:name="android.pe...
<uses-permission android:name="android.pe...
+ <uses-sdk android:minSdkVersion="7"/>
</manifest>

41. 3.x “Honeycomb”
●
Motorola Xoom
●
February 2011
●
Linux kernel 2.6.36
Photo: flickr.com/quinnanya/
CC / Some rights reserved

42. Publishing to Android Market
Sometimes the easy part is
writing the app. The hard part is
getting it published.

43. .APK format explained
●
.JAR and .ZIP
●
Typically includes:
META-INF/
res/
AndroidManifest.xml
classes.dex
resources.arsc
●
Native apps also include:
libs/armeabi/

44. Two publishing options
Ministro Bundling Qt
+ dev friendly + UX
+ updates + BIC
+ multiple archs + custom fixes
+ space / bandwidth - space / bandwidth
- UX - less archs
- updates - no updates
- BIC

45. Bundling Qt with your app
Target one arch (ARMv5)
Set relatively high API level
Only include the actually needed libs
Disable Ministro dependencies
Beware of SSL certs
Here be dragons :-)

46. Publishing with Ministro
cd android/
ant release
This produces Fly-unsigned.apk in the
shadowbuild directory.

47. Getting an A.M. account
http://market.android.com/publish
You'll need:
A credit card with 25USD
A phone number

48. Name, email and phone

49. Paying

50. Credit-card needed

51. One time fee of 25USD

52. Order sent

53. Distribution agreement

54. We can publish free apps!

55. Sign up for merchant

56. We can make money!

57. Signing the .APK
Create key
keytool -genkey -v -keystore cutehacks-
release-key.keystore -alias cutehackskeystore
-keyalg RSA -keysize 2048 -validity 10000
Sign package
jarsigner -verbose -keystore cutehacks-
release-key.keystore android/bin/Fly-
unsigned.apk cutehackskeystore

58. Verifying the signature
Verify signature
jarsigner -verify -verbose Fly-unsigned.apk
585 Tue ... META-INF/MANIFEST.MF
706 Tue ... META-INF/CUTEHACK.SF
1327 Tue ... META-INF/CUTEHACK.RSA
sm 2932 Tue ... AndroidManifest.xml
sm 1500 Tue ... resources.arsc
sm 3064 Tue ... res/drawable-hdpi/icon.png
sm 1543 Tue ... res/drawable-ldpi/icon.png
sm 2347 Tue ... res/drawable-mdpi/icon.png
sm 86680 Tue ... classes.dex
sm 164020 Tue ... lib/armeabi/libfly.so
s = signature was verified m = entry is listed in manifest
Rename Fly-unsigned.apk to Fly-release.apk

59. Actually publishing
http://market.android.com/publish
You'll need:
Signed APK (max 50MB)
High-res app icon (512x512)
Two screenshots (min 320x480)
Title & Description

60. Upload .APK

61. Set name and screenshots

62. In the store

63. Installation UX with Ministro
Press app
Press “FREE”
Press “OK”

64. Installation UX with Ministro
Press app
Press “Yes”
Press “Ministro”

65. Installation UX with Ministro
Press “Install”
Press “Accept”
Press “Yes”

66. Installation UX with Ministro

67. 2.0/2.1 “Eclair”
●
Motorola Droid
●
October 2009
●
Linux kernel 2.6.29
Photo: flickr.com/quinnanya/
CC / Some rights reserved

68. Conclusion
Let's summarize and look at the
future.

69. Summary
Qt on mobile: Potential bright future
Necessitas: Out-of-the-box with rough edges
Android Market: Quick and easy

70. Qt's future
Qt 5 – Qt Quick and scenegraph
“The next billion”
iOS and BBX
Open Governance

71. Information on Necessitas
Mailinglist for users:
http://groups.google.com/group/android-qt
Mailinglist for devs/contributors:
https://mail.kde.org/mailman/listinfo/necessitas-devel
Repositories:
http://community.kde.org/Necessitas/Repositories
Wiki:
http://sourceforge.net/p/necessitas/home/necessitas/

72. It's already possible
Fly in Fly installed
Android Market on phone
http://bit.ly/cutefly
https://market.android.com/details?id=com.cutehacks.fly

73. Questions?
Thank you!
@snowpong (Twitter)