Jan 1, 2016
Jan 1, 2020 (Retired)
Bijoy Singh Kochar (BijoySingh)
Ravindra Kumar (ravidsrk)
Bijoy Singh Kochar (BijoySingh)
Source code


Android Basics Library

This library offers some barebone code for android common to most applications. It provides simple classes and pre-written functions for:

  • Internet Access
  • SharedPreferences / DataStore storage and retrieval
  • File read and write
  • Recycler View
  • Some other basic functions like dp2pixel, etc.
  • Marshmallow Permissions Support
  • Simple Profiler
  • Parallel Execution
  • Text Utilities


The library is on Jcenter, so usage is really simple. Add the following dependency in your app's build.gradle:

dependencies {
    implementation 'com.github.bijoysingh:android-basics:5.1.1-x'

// compile 'com.github.bijoysingh:android-basics:5.0.0' for Android Support Lib v28.0.0
// compile 'com.github.bijoysingh:android-basics:4.4.3' for Android Support Lib v27.1.1
// compile 'com.github.bijoysingh:android-basics:4.2.2' for Android Support Lib v27.1.0
// compile 'com.github.bijoysingh:android-basics:4.0.0' for Android Support Lib v27.0.2
// compile 'com.github.bijoysingh:android-basics:3.1.2' for Android Support Lib v26
// compile 'com.github.bijoysingh:android-basics:2.1.0' last stable version

You might need to also include these in case you use the corresponding dependencies

dependencies {

    // For internet access
    compile 'com.mcxiaoke.volley:library:1.0.17'
    // For Timestamp utility
    compile 'net.danlew:android.joda:2.8.1'

Basic Usage

Internet Access

Internet access is simpler than ever. I have added a simple DefaultQueryExecutor class for convenient usage.

DefaultQueryExecutor executor = new DefaultQueryExecutor.Builder(context)
    .setOnQueryListener(queryListener) // optional
    .setAuthenticationProvider(authenticationProvider) // optional
    .setTimeout(DefaultRetryPolicy.DEFAULT_TIMEOUT_MS) // optional
    .setMaxRetries() // optional
    .setRetryBackoffMultiplier() // optional

You can create a OnQueryListener object or have the activity making the request implement it.

QueryParams query = QueryParams.Builder(url)
    .setCache(cacheFilename) // optional: the filename you want to save the result to as a cache
    .setQueryIdentifier(queryId) // optional
    .setAuthenticated(isAuthenticated) // optional: tells if you want to use the genAuthenticationData method of the AuthenticationProvider
    .setMethod(Request.Method.POST) // optional
    .setExtra(extraHashMap) // optional
    .addExtra(key, value) // optional

Making a query is really simple too

executor.send(query, data);

Extend the QueryExecutor class for more control on your queries and for supporting more things.

public class MyQeuryExecutor extends MyQeuryExecutor {

SharedPreferences storage and retrieval

Use the class and built in functions using put and get.

PreferenceManager preferences = new PreferenceManager(context);
preferences.put(KEY, your_variable);
preferences.get(KEY, your_default_variable);

Optionally Extend the PreferenceManager class.

public class Preferences extends PreferenceManager {
    public String getPreferencesFolder() {


If you plan to use SharedPreferences in Services due to recent changes in Android SharedPreferences this may not be your best option. You can go for a solution of use the library 'net.grandcentrix.tray:tray:0.11.1' But I have recently seen that it has bugs like deletion during updates. Try the new class DataStore described next:

Async safe Store

Use this class for saving / retrieving content using put and get. You can get the content from services / main system alike. The access will be fast and will be the same.

Store storage = Store.get(context);
storage.put(KEY, your_variable);
storage.get(KEY, your_default_variable);

Note: If you were using the older DataStore class, you can migrate to the Store API using: dataStore.migrateToStore(store);

  • Store offers no context solution vs DataStore
  • Compressed storage - less storage space
  • Much much faster than DataStore
  • It also allows you to have multiple smaller Stores, with names, so you can segregate your store based on use cases. Store.get(context, NAME)
  • Further it allows for a VersionedStore, which allows for you to specify a version with the Store. And migrations are handled gracefully, using a Migration object VersionedStore.get(context, NAME, version) or VersionedStore.get(context, NAME, version, migration)

Image operations

This library used to support Image operations, but they are being removed as
directly using Picasso and Fresco for these is the best idea.

File read and write

To store and retreive some text, some basic support code is available. This is needed if you want to save some file/ json you receive from the server to act as cache.

FileManager.write(context, filename, text_to_write);
String textRead =, filename);

Asynchronous write is now supported (I will be updated the way to access these functions to ease usage)

FileManager.writeAsync(context, filename, text_to_write);

Some other useful functions

These are some common useful functions. These will expand with time.

DimensionManager.dpToPixels(context, dp);
DimensionManager.pixelsToDp(context, pixels);


I know toasts are pretty simple to use in Android. But I personally got pissed with typing the Toast.LENGTH_SHORT and a show() everytime. So I built a simple wrapper around it to reduce this boilerplate code. Using a ToastHelper static methods, R.string.your_toast_message);, "your toast message");

Using a ToastHelper object

ToastHelper toastHelper = new ToastHelper(context);"your toast method");;
toastHelper.showLong("your toast method");

Locale String Format Wrappers

LocaleManager.toString(Character/Float/Double/Integer/Boolean variable);
LocaleManager.toString(Float/Double variable, precision);

This function will convert your variable to the String to these using the Locale. This functions is a wrapper around the code String.format. The function will prevent Lint Warning for the same.

Recycler View

Simple Recycler View

This is a recycler view with a simple one kind of view item. Extend the Recycler View Holder -> This is the holder for the view contents of one item. We will show you how to use this for a simple item

 * @example
 * View Item inside a layout R.layout.content_item
 *  ------------------------------------
 * |   TextView                         |
 * |   id -> content                    |
 *  ------------------------------------
public class YourViewHolder extends RecyclerViewHolder<YourItem> {

     * @example
     * TextView content;

    public YourViewHolder(Context context, View itemView) {
      super(context, itemView);
       * @example
       * content = (TextView) itemView.findViewById(;
    public void populate(YourItem data, Bundle bundle) {
        // Populate your view. You can set on click listeners etc.
         * @example
         * content.setText(data.getContent());

Extend the Recycler View Adapter, this is the controller to your recycler view. Most of the basic functions have already been done for you.

public class YourAdapter extends RecyclerViewAdapter<YourItem, YourViewHolder> {

   * The recycler view adapter constructor
   * @param context the application/activity context
  public YourAdapter(Context context) {
    super(context, R.layout.your_layout_file, YourViewHolder.class);
// Using this adapter is easy
YourAdapter yourAdapter = new YourAdapter(context);

// You can do a lot from this adapter. This will take your list of items
yourAdapter.addItem(item, position);

// You can get the default layout manager as well from the adapter.
// A layout manager controls the way your recycler view is rendered.
// This is basically like a simple list - LinearLayoutManager or
// a grid layout - GridLayoutManager

Setup your recycler view You could either do the following

    recyclerView = new RecyclerViewBuilder(context)
        .setView(activity, // or use this
        .setRecyclerView(recyclerView) // or use this
        .setOnScrollListener(onScrollListener) // optional
        .setLayoutManager(layoutManager) // set the layout manager

or the usual way will also work of course.

Multi View Recycler View

A common use case for recycler views is to use it with multiple view holders / views. This involves some common setup which has been taken care for you here.

public class YourAdapter extends MultiRecyclerViewAdapter<YourItem> {
  public YourAdapter(
    Context context,
    List<MultiRecyclerViewControllerItem<YourItem>> items) {
    super(context, items);

  public int getItemViewType(int position) {
    // Return an int value indicating your view type for the given position
// To set this up, you need to create this list of MultiRecyclerViewControllerItem items
// Each of these items maps, view type to some common properties like:
MultiRecyclerViewControllerItem<YourItem> item = new MultiRecyclerViewControllerItem.Builder<YourItem>()
    .viewType(VIEW_TYPE) // the view type for this view holder
    .spanSize(VIEW_SPAN) // optional for grid view: the number of columns the view spans
    .layoutFile(R.layout.your_view_item) // the view item layout for this view type
    .holderClass(YourRecyclerViewHolder.class) // the class of the holder

// You can create a list of these items for each view, and set it to the adapter constructor.
YourAdapter adapter = new YourAdapter(context, items);

// Optional for grid views: using this handles the span size properties for you.


If you have to repeatted format your Dates here is a simple wrapper on your code

// Get Today's formatted date

// Get any Date's formatted date
DateFormatter.getDate("dd mmmm yyyy", date);
DateFormatter.getDate(date, locale);
DateFormatter.getDate("hh:MM a, dd mmmm yyyy", date, locale);

// Some default formats exist (a lot more exist)

Threading and Async

Hate writting a lot boilerplate code to use Executors or AsyncTasks, we got you covered

// Want to run something in background and handle it in UI thread
SimpleAsyncTask<String> task = new SimpleAsyncTask<>() { ... }

// Want to run something huge, with high priority, but in background
// Simply run something in the background

// Or get more control
SimpleThreadExecutor executor = new SimpleThreadExecutor();

Async Tasks have an issue that they only work synchronously. This is generally a problem for doing more things. Introducing MultiAsyncTask for this usecase

MultiAsyncTask.execute(this, new MultiAsyncTask.Task<Result>() {
  public Result run() {
    return doHeavyOperation();

  public void handle(Result result) {
List<String> names = ...;
Parallel<String, Integer> parallel = new Parallel();
parallel.setListener(new ParallelExecutionListener<String, Integer>() {


Handling your permissions for Marshmallow made simpler, and cleaner

// Could be more than one permissions here
String[] permissions = new String[]{Manifest.permission.ACCESS_FINE_LOCATION};

// Initialise the manager object, with required permissions
PermissionManager manager = new PermissionManager(context, permissions);

 * Or set them as you need them
 * PermissionManager manager = new PermissionManager(context);
 * manager.setPermissions(permissions);

Now checking for permission is really simple


And requesting for permissions too

// Using an access code fixed in the library

// Using a custom access code, for more control

It will automatically detect which permissions are already allowed, and will request the missing permissions. To handle a response, the procedure is same as that in the usual case. You override the onRequestPermissionsResult listener.

Intent Utils

Some common actions around intents To share a text to other applications on the device

new IntentUtils.ShareBuilder(context)
  .setChooserText("Share using...") // Optional

IntentUtils.openAppPlayStore(context, packageName);

Text Utils

Some common actions which need to be done with Text is now part of the library

// To copy text to a clipboard
TextUtils.copyToClipboard(context, textToCopy);

// To check if a string is null or empty

// Check if two nullable strings are equal
TextUtils.areEqual(string1, string2);
TextUtils.areEqualNullIsEmpty(string1, string2);

Bottom Sheet Fragment

There is a lot of boiler plate code using the bottom sheet fragment. This code allows for using that The XML for the activity MUST be surrounded by a CoordinatorLayout

<?xml version="1.0" encoding="utf-8"?>

You also need a layout file for the bottom sheet. Let's say it's layout_bottom_sheet.xml

public class BottomSheet extends SimpleBottomSheetFragment {
  public int getLayout() {
    return R.layout.layout_bottom_sheet;

  public void setupView(View contentView) {
    // find views inside the layout_bottom_sheet.xml

View Pager Activity and Fragment

There is a lot of boiler plate code which needs to be done for view pagers. This will save that for you

public class YourActivity extends ViewPagerActivity {

  protected Fragment getPageFragment(int position) { ... }

  protected void onPageChanged(int position) { ... }

  protected int getPagesCount() { ... }

  protected int getViewPagerResourceId() {
public class YourFragment extends SimpleFragment {
  protected int getLayoutId() {
    return R.layout.your_fragment_layout;

  protected void onCreateView() {
    // Simply use like a activity
    TextView yourTextView = (TextView) findViewById(;

Random Helper

Sometimes you need to generate secure random numbers like IDs etc which are alphanumeric etc.

// Get a alpha numeric random string of length 16

// Get a alpha numeric random string of a fixed length

// Get a Big Integer which has upto a fixed approx length (this is because we use nearest power of 2)

Database Support

Removing this support too as Reflection is not very efficient or reliable. Try using google's Room library.

JSON Parsing

Removing this support too as Reflection is not very efficient or reliable.


Copyright 2016 Bijoy Singh Kochar

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
See the License for the specific language governing permissions and
limitations under the License.

Reference Licensing


Apache 2.0 License
Copyright (C) 2014,2015,2016 Xiaoke Zhang
Copyright (C) 2011 The Android Open Source Project


Apache 2.0 License