'Conversion to Dalvik format failed with error 1' and 'java.lang.IllegalArgumentException: already added: '

Recently we moved to Android SDK tools Rev 15 , In my opinion it has may problems comparing to previous versions of the SDK and should stick with the previous version if you are developing a huge applications and have library projects referenced.

Today, I got this error and few hours of Googling found the solution,

Remove the source folder link in Project properties->Java Build Path->Source

Clean and add the projects back, You will see that it will add the projects as jar files under "Library Projects" not as project_src anymore.

How to do a simple visible animation in Android

public void showConfigurationBar() {

AnimationSet set = new AnimationSet(true);

Animation animation = new AlphaAnimation(0.0f, 1.0f);

animation.setDuration(500);

set.addAnimation(animation);

animation = new TranslateAnimation(Animation.RELATIVE_TO_SELF, 0.0f,

Animation.RELATIVE_TO_SELF, 0.0f, Animation.RELATIVE_TO_SELF,

1.0f, Animation.RELATIVE_TO_SELF, 0.0f);

animation.setDuration(500);

set.addAnimation(animation);

RelativeLayout configBar = findViewById(R.id.baridhere);

configBar.setVisibility(View.VISIBLE);

configBar.startAnimation(set);

}

How to generate a MD5 Hash in Android

public static String getMd5Hash(String input) {

try {

MessageDigest md = MessageDigest.getInstance("MD5");

byte[] messageDigest = md.digest(input.getBytes());

BigInteger number = new BigInteger(1, messageDigest);

String md5 = number.toString(16);

while (md5.length() < 32)

md5 = "0" + md5;

return md5;

} catch (NoSuchAlgorithmException e) {

Log.e("MD5", e.getLocalizedMessage());

return null;

}

}

Eclipse Layout Editor Graphical Layout is not Showing or missing ?

Specify the Android Layout Editor as the default for Android XML files under Preferences -> General- >Editors->File Associations.

1. If Android layout editor is missing Add Android Layout Editor and make it default.

2. Close eclipse and restart. Otherwise this will not work.

CountDownTimer Error: Can't create handler inside thread that has not called Looper.prepare()

Today I was getting this error "Can't create handler inside thread that has not called Looper.prepare()" in a CountDownTimer. All this time this code used to work perfectly but suddenly it stopped.

Problem is, in CountDownTimer.java (Android source code) it creates a mHandler inside the code which makes the caller should call the CountDownTimer class on UI thread which is not possible in my case. So I created a separate Timer class,

Timer cTimer = new Timer();

private final static int START_FROM = 60;

cTimer.scheduleAtFixedRate(new TimerTask() {

int i = START_FROM ;

public void run() {

Log.d(TAG, "Comparison will start in:" + i--);

if (i< 0) {

cTimer.cancel();

// Do something

}

}

}, 0, 1000);

How to enable/disable Mobile Data on Android 2.3

Today, colleague asked me whether i know how to enable and disable mobile internet on Android ? Actually, I was curious about this for sometime and never had the time to look into how to do this. So this is how to do it.

I tired it on Android 2.3 i tried this code and it worked! When I looked into Android source code I saw this method is available 2.2 R1 up.

  private boolean getMobileDataEnabled() {
        try {
            Method method = connectivityManager.getClass().getMethod("getMobileDataEnabled");
            return (Boolean)method.invoke(connectivityManager);
        } catch (Exception e) {
            e.printStackTrace();
            return false;
        }
    }
    private void setMobileDataEnabled(boolean on) {
        try {
            Method method = connectivityManager.getClass().getMethod("setMobileDataEnabled",
                    boolean.class);
            method.invoke(connectivityManager, on);
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

If you are using 2.2 R1 or later try this code.

android.content.OperationApplicationException: wrong number of rows: 0

Today I got this error tying to update a contact in Android 2.3 Nexus S device which was working fine on Motorola Milestone (Android 2.1 - update 1). Reason was I was getting the "withExpectedCount" parameter as 1

ops.add(ContentProviderOperation. newInsert(addCallerIsSyncAdapterParameter(ContactsContract.Data.CONTENT_URI))

.withValue(ContactsContract.Data.RAW_CONTACT_ID, contact.getId())

.withValue(ContactsContract.Data.MIMETYPE, CommonDataKinds.Phone.CONTENT_ITEM_TYPE)

.withValue(CommonDataKinds.Phone.NUMBER, phone)

.withValue(CommonDataKinds.Phone.TYPE, cm.getType()).withExpectedCount(1).build());

When i removed it it worked fine .. Looks like if the original and updating content values are same it does not update the row :|