Applying MD5 Algorithm In Android

Hello developers, have you ever given a thought about securing your content when it is being used in communication? If yes then this blog might help you in achieving so.

MD5 stands for Message Digest(5 denotes the series), which is a hashing algorithm used for generating the fingerprint of the content. It was designed in 1991 by Ronald Rivest at MIT.

MD5 algorithm is a one way hashing process which means you cannot generate original text from the hash code.It always produces the same output for the similar input, and this property is used for checking the data integrity. You can compare the two hash codes at destination(one which is received from server and one which is already present at destination) and check whether the files contains the same content or not.

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Upload Failed : You uploaded a debuggable APK

It was quite late in the evening and I was about to wrap up my work. Suddenly I got a call form my client in Skype and he shared his concerns of uploading the build to production. Although it was late, I thought to help him before I close the day, since that guy is in the middle of his day time (in US). Now mind set is to spend time on the issue. I started looking into the issue.

The issue is, while he (my client) started uploading the APK file into the Android store, he is receiving the below rejection message from the store.

Upload Failed

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Classic Bluetooth Implementation

This is basically a kind of tutorial which will be useful if you are learning and implementing bluetooth in your android app. In this tutorial I have shared the code for scanning of the Classic Bluetooth devices in range and fetching the paired devices list, moreover I will find some time to write about the implementation of further aspects of classic bluetooth.

Android offers bluetooth API that lets you share your stuff wireless. As per Bluetooth standards it offers you short range (10 m approx.) device connectivity. This API let application to the Bluetooth devices and enable point to point or multipoint wireless feature. Here we are discussing about the Classic Bluetooth that consumes more battery life.

Bluetooth devices with low power requirement Android 4.3 (API level 18) introduces support for Bluetooth Low Energy, I have talked about it in my last blog. We will get to understand about  the API by creating a sample application that lets you share you stuff over bluetooth.

To start with we will first find to check that whether our device support bluetooth or not. For this we need to use Bluetooth Adapter class. Bluetooth Adapter is some sort of entry – point for all bluetooth interaction.

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Bluetooth Low Energy (BLE)

Don’t you think Bluetooth plays a significant role in making the smart phones smart? So let’s talk about something smarter i.e. Bluetooth Smart or BLE. As far as the BLE or the Bluetooth low energy is concerned it is not just a feature it’s a new technology

it was first proposed by NOKIA in 2006 with the name WIBREE. And now the devices which are equipped with BLE are called as Bluetooth Smart devices and the devices which has both Bluetooth classic and the BLE are called as Bluetooth Smart Ready devices.

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SeekBar Customization for Android Development

If you want some customization in the seekbar which you use while developing android apps, there are several ways of doing this. You can customize seek bar with the help of the xml or you can make it impressive even programmatically.

Let’s have a look if you want to change its appearance with the help of xml

First of all the progress Drawable attribute of the seekbar should be set as the xml file in the drawables folder as

android:progressDrawable=”@drawable/progress_seekbar”

The overall seek bar implementation in the layout xml should look something like this

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Behavior of WinJS.Promise.Join during Exceptions

Introduction

Promise is an object, which promises the user to get back the values or do some task after performing the promised activity without hampering the main UI. The execution of the other activities will work as normal. So in single word we can say, it is asynchronous.

The JOIN method of the Promise works like a waiter in the restaurant, waiting for the whole order from a table from each person. We can club separate promise objects and join them together. Join ensures to perform a task after all the promise objects finished their execution.

Queries encountered on the above

On all the above, I encountered the query,

  • what will happen when any of the Promise gets an error ?
  • Will it able to club the output and wait for the promises ? OR it will quite the execution ? Etc. etc.

After some of the homework and trials below are my findings. Continue reading

Backup API Implementation: Creating Backup of App Data and Settings Over Cloud

How about creating a backup setting for an android application, so that when the application is uninstalled the personal settings it does not get erased permanently, instead the settings is stored on the cloud and the next time when you install the application it asks you to restore the settings. Interestingly, it can restore the settings when you install the application into other device too. It can be achieved through Backup API provided by Google. You will find it really interesting, easy and useful.

It’s not for the synchronizing of the data with other apps or storing the data which could further be used as in the case of SQLite . Also there is no method to access the backed up data other than the API and neither any way to make the Backup status known. This makes it easier to implement and lesser code it requires.

Android currently supports and provides helpers to backup and restore the complete data of the Shared Preferences or the internal storage if they are light weighted i.e. less than one megabyte.

For the implementation of Backup API the first and the foremost thing which has to be done is create the API key for your application by clicking on the link

https://developer.android.com/google/backup/signup.html?csw=1
and registering your application by giving the appropriate package (the package name of your app)

Android Backup

Android Backup

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