Shailesh Shukla Android Life: June 2012

Friday, June 29, 2012

How to format the SDCard through ADB in Android?

shailesh@shailesh-desktop:~$ adb -e shell rm -r /mnt/sdcard/*

Tuesday, June 19, 2012

Troubleshooting Android’s ‘adb devices’?

I’ve been playing around a bit with Android development lately, and — for the second time — spent a while trying to work out why

adb
devices

wasn’t showing me anything:

$ adb devices
List of devices attached

$

Thanks, adb. I’m pretty sure I’ve got a Dream plugged in there, you know. I did get it working in the end, so I thought I’d write up some of the troubleshooting steps so that I’ll have something to refer to the next time I run into this problem.

First off, it’s worth mentioned that if you’re on Windows, you apparently need to install some USB drivers first (and it appears that the 32-bit and 64-bit versions aren’t compatible, so you need to pick the right version too). I’m not using Windows, though, so I don’t know a whole lot about this step.

However, life’s not all rosy on Linux: the adbcommand scans /dev/bus/usb/ rather than /proc/bus/usb/ (as provided by usbdevfs) or /sys/bus/usb/ (ditto, sysfs). This is absolutely the right thing to do (lsusb works the same way), but it means that there’s another step (udev) between the device detection and being able to use the device.

Evidently some of the default udev rules (possibly only on some distributions; in particular, on Ubuntu) create device nodes that aren’t world-readable, meaning that the device node is created, but adb can’t read it. The easiest way to tell whether you’re having this problem is to kill the adb daemon and restart it as root:

$ adb kill-server
$ sudo adb start-server
* daemon not running. starting it now *
* daemon started successfully *
$ adb devices

(The adb daemon appears in ps as “

adb
fork-server server

”, by the way.) I’ve also seen suggestions that you should be able to run

sudo
adb devices

to start the server as root, but when I tried that I ended up with a daemon running as myself again.

If this is your problem, the fix is mentioned on the setup page.I mentioned previously: you create a file called something like/etc/udev/rules.d/51-android.rules that contains rules telling udev to make the device node world-writable when a matching device is found.

The example rule provided in the Developer Guide matches any HTC devices, which might be a bit wide-ranging: you could presumably restrict the match to just the device’s id. (The HTC Dream and Magic share the same device id, 0bb4:0c02, or, strangely,0bb4:0c01when booting into HBOOT/fastboot mode.)

Finally, there’s one very important thing that I’d completely forgotten about: if the devices appears in lsusb output but

adb
devices

still shows nothing,check that the phone is set up to allow debugging via USB(Settings⇒Applications⇒Development⇒USB debugging). If this is off, you’ll see nothing… and that was the step I’d forgotten about.

Things went much better after that: I think I might have had to restart the phone once when it was being insistent that there wasn’t a USB connection, but other than that, it’s all happy:

$ adb devices
List of devices attached
HT851N003417  device

$

One more thing: while looking around, I found an issue reported against the Android project that states that adb is broken against Linux kernel versions 2.6.27 and later, with identical symptoms. I’m currently using 2.6.24, so I can’t test it, but it’s worth being aware of.

Saturday, June 16, 2012

How to change the android rules in ubuntu through terminal in ubuntu?

The first thing to do is download android sdk from http://developer.android.com/sdk/index.html and extract it to wherever you want then log in as root and create a new plain text document in

/etc/udev/rules.d

and name it

51-android.rules

In the text document type:

SUBSYSTEM=="usb",SYSFS{idVendor}=="22b8",MODE="0666"

and save it to that directory.Then open Terminal and execute

chmod a+r /etc/udev/rules.d/51-android.rules

Restart the computer and go to the adb directory and execute

./adb devices

If the device ID shows instead of the question marks you should be ready to execute any adb commands.ENJOY!
(Dont forget to enable USB debugging on you're phone!)

I followed following step so that i can get writing permission in rules file,so first step login through root....

shailesh@shailesh-desktop:~$ sudo -i
root@shailesh-desktop:~# cd /
root@shailesh-desktop:/# cd etc/
root@shailesh-desktop:/etc# cd udev/
root@shailesh-desktop:/etc/udev#
root@shailesh-desktop:/etc/udev# cd rules.d/
root@shailesh-desktop:/etc/udev/rules.d# chmod 777 51-android.rules

//No we can write and save after saving type the below command....

root@shailesh-desktop:/etc/udev/rules.d# chmod a+r 51-android.rules

Friday, June 15, 2012

Design Layout For Multiple Screens in android?

You need to create different layout for diff screen size. Support all screen you need to create following layout:

1-Low density Small screens QVGA 240x320 (120dpi):
layout-small-ldpi (240x320)
layout-small-land-ldpi (320x240)

2-Low density Normal screens WVGA400 240x400 (x432) (120dpi):
layout-ldpi (240 x 400 )
layout-land-ldpi (400 x 240 )

3-Medium density Normal screens HVGA 320x480 (160dpi):
layout-mdpi (320 x 480 )
layout-land-mdpi (480 x 320 )

4-Medium density Large screens HVGA 320x480 (160dpi):
layout-large-mdpi (320 x 480 )
layout-large-land-mdpi (480 x 320)

5-Galaxy Tab ( 240 dpi ):
layout-large (600 x 1024)
layout-large-land (1024 x 600)

6-High density Normal screens WVGA800 480x800 (x854) (240 dpi):
layout-hdpi (480 x 800)
layout-land-hdpi (800 x 480)

7-Xoom (medium density large but 1280x800 res) (160 dpi):
layout-xlarge (800 x 1280)
layout-xlarge-land (1280 x 800)

8- Other

layout-normal-mdpi -> 320x480
layout-normal-hdpi -> 800x480 and 854x480 (adjusted in the code)
layout-normal-ldpi -> 400x240
layout-large-mdpi -> 800x480 tablet (mostly the same as the layout-normal-hdpi layout, but needs to be in this folder)
layout-small-ldpi -> 320x240

Also add following code in .manifest file:

<supports-screens
android:smallScreens="true"
android:normalScreens="true"
android:largeScreens="true"
android:xlargeScreens="true"
android:anyDensity="true" />

Sunday, June 10, 2012

keytool -genkey error: Keystore file does not exist(Ubuntu) in Android ?

Below command will generate the KeyStore..........
keytool -list -alias [KEYNAME] -keystore [STORE FILENAME] -storepass [STORE PASSWORD] -keypass [KEY PASSWORD]

shailesh@shailesh-desktop:~$ cd .android/

shailesh@shailesh-desktop:~/.android$ keytool -list -alias androiddebugkey -keystore debug.keystore -storepass android -keypass android
keytool error: java.lang.Exception: Keystore file does not exist: debug.keystore

SOLUTION

Generating a key pair (and a new keystore) has to be done as a separate operation to creating a self-signed certificate for that key.

i.e.

keytool -genkey -alias myKey -keystore store.jks

keytool -selfcert -alias myKey -keystore store.jks

shailesh@shailesh-desktop:~/.android$ keytool -genkey -alias debug -keystore store.jks
Enter keystore password:

Above command will ask for the password and other information and hence the key is generated.

Tuesday, June 5, 2012

List the Stock Launchers for Android ?

Here are a few links

Android-Launcher-Plus

Modified launcher

http://code.google.com/p/adw-launcher-android/

http://golauncher.goforandroid.com/

http://launcherpro.com/

http://forum.xda-developers.com/showthread.php?t=538871

Monday, June 4, 2012

Android emulator: How to monitor network traffic?

There are two ways to capture network traffic directly from an Android emulator:

Copy and run an ARM-compatible tcpdump binary on the emulator, writing output to the SD card, perhaps (e.g. tcpdump -s0 -w /sdcard/emulator.cap).
Run emulator -tcpdump emulator.cap -avd my_avd to write all the emulator's traffic to a local file on your PC

In both cases you can then analyse the pcap file with tcpdump or Wireshark as normal.

try wireshark http://www.wireshark.org/

Capture network trace in Android devices ?

After finding a bug, the next step for a tester is to find whose fault is it ?

Normally a software interacts a lot with servers. It is then quite useful to capture the network exchanges between the software and the servers to find what is really happening behind the user interface. For Android devices, we can use Android Debug Bridge (ADB), tcpdump-arm and wireshark to analyse network packages. First, you need to have Wireshark and ADB installed in your computer (here’s a bit oftutorial). Then, I’ll briefly explain how to use tcpdump-arm in your Android devices to capture a network trace during use case scenario.

1. Download tcpdump-arm from here

2. Open command-promt where your ADB tools located. Put your tcpdump-arminto /data/local in your Android device through this command :

adb remount

adb push tcpdump-arm /data/local

3. Go inside Android devices through this command :

adb shell
cd data/local

4. Give tcpdump-arm execute permission.

chmod 777 tcpdump-arm

5. We need to define in which interface we want to listen to the packages. If you run the command below, you’ll see the list of interfaces registered on your device. Normally we find three interfaces: svnet0, pdp0, and l0.

./tcpdump-arm -D

6. Since I want to capture packets coming from data network, I choose to listen to interface: pdp0. (Still remember the famous Packet Data Protocol Context learnt at school ). I specify also the output file in which I’d like it to be read through Wireshark later on.

./tcpdump-arm -i pdp0 -w capture.pcap

7. FYI, the option of pdp0 is available when you use the firmware Gingerbread for Samsung Galaxy 2. When you use Ice Scream Sandwich, there’ll be only two options offered: svnet0 and l0. You can either listening to svnet0, but sometimes I also try with option -s 0 to make it capture the full packets and later on I filter what I want in wireshark.

./tcpdump-arm -s 0 -w capture.pcap

8. After finish the test, run Ctrl+C to stop the capture. Move the output filecapture.pcap from the device into your computer and open it in Wireshark. Here you can do whatever filter you want to find your exchange package.

adb pull data/local/capture.pcap

These tricks have helped me a lot to prevent myself from blaming the developpers for some faults since it’s proved that the bug comes from another source . Have fun!

Friday, June 1, 2012

How to avoid spinner listener to get fire before Adapter is set in android?

Solution

1. in onCreate(), count how many Spinner (or Spinner) widgets you have in the view. (mSpinnerCount)

2. in onItemSelected(), count how often it has triggered. (mSpinnerInitializedCount)

3. when (mSpinnerInitializedCount < mSpinnerCount) == false, then execute the code meant for the user

public class myActivity extends Activity implements OnItemSelectedListener
{
//this counts how many Spinner's are on the UI
private int mSpinnerCount=0;
//this counts how many Spinner's have been initialized
private int mSpinnerInitializedCount=0;
//UI reference
private Spinner mSpinner;

@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.myxmllayout);

//get references to UI components
mSpinner = (Spinner) findViewById(R.id.myspinner);

//trap selection events from spinner
mSpinner.setOnItemSelectedListener(this);

//trap only selection when no flinging is taking place
mSpinner.setCallbackDuringFling(false);

//
//do other stuff like load images, setAdapter(), etc
//

//define how many Spinner's are in this view
//note: this could be counted dynamically if you are programmatically creating the view
mSpinnerCount=1;
}

public void onItemSelected(AdapterView<?> parent, View view, int position, long id)
{
if (mSpinnerInitializedCount < mSpinnerCount)
{
mSpinnerInitializedCount++;
}
else
{
//only detect selection events that are not done whilst initializing
Log.i(TAG, "selected item position = " + String.valueOf(position) );
}
}
}

Why this works

this solution works because the Spinner finishes initialization long before a user is physically able to make a selection.