├── .github └── ISSUE_TEMPLATE │ ├── custom.md │ └── new-issue-template.md ├── .gitignore ├── .idea ├── $CACHE_FILE$ ├── codeStyles │ └── Project.xml └── misc.xml ├── CODE_OF_CONDUCT.md ├── CONTRIBUTING.md ├── LICENSE ├── README.md └── images └── interview.png /.github/ISSUE_TEMPLATE/custom.md: -------------------------------------------------------------------------------- 1 | --- 2 | name: Custom issue template 3 | about: Describe this issue template's purpose here. 4 | title: '' 5 | labels: '' 6 | assignees: '' 7 | 8 | --- 9 | 10 | 11 | -------------------------------------------------------------------------------- /.github/ISSUE_TEMPLATE/new-issue-template.md: -------------------------------------------------------------------------------- 1 | --- 2 | name: New Issue template 3 | about: Describe this issue template's purpose here. 4 | title: '' 5 | labels: '' 6 | assignees: '' 7 | 8 | --- 9 | 10 | 11 | -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | # Built application files 2 | *.apk 3 | *.aar 4 | *.ap_ 5 | *.aab 6 | 7 | # Files for the ART/Dalvik VM 8 | *.dex 9 | 10 | # Java class files 11 | *.class 12 | 13 | # Generated files 14 | bin/ 15 | gen/ 16 | out/ 17 | # Uncomment the following line in case you need and you don't have the release build type files in your app 18 | # release/ 19 | 20 | # Gradle files 21 | .gradle/ 22 | build/ 23 | 24 | # Local configuration file (sdk path, etc) 25 | local.properties 26 | 27 | # Proguard folder generated by Eclipse 28 | proguard/ 29 | 30 | # Log Files 31 | *.log 32 | 33 | # Android Studio Navigation editor temp files 34 | .navigation/ 35 | 36 | # Android Studio captures folder 37 | captures/ 38 | 39 | # IntelliJ 40 | *.iml 41 | .idea/workspace.xml 42 | .idea/tasks.xml 43 | .idea/gradle.xml 44 | .idea/assetWizardSettings.xml 45 | .idea/dictionaries 46 | .idea/libraries 47 | # Android Studio 3 in .gitignore file. 48 | .idea/caches 49 | .idea/modules.xml 50 | # Comment next line if keeping position of elements in Navigation Editor is relevant for you 51 | .idea/navEditor.xml 52 | 53 | # Keystore files 54 | # Uncomment the following lines if you do not want to check your keystore files in. 55 | #*.jks 56 | #*.keystore 57 | 58 | # External native build folder generated in Android Studio 2.2 and later 59 | .externalNativeBuild 60 | .cxx/ 61 | 62 | # Google Services (e.g. APIs or Firebase) 63 | # google-services.json 64 | 65 | # Freeline 66 | freeline.py 67 | freeline/ 68 | freeline_project_description.json 69 | 70 | # fastlane 71 | fastlane/report.xml 72 | fastlane/Preview.html 73 | fastlane/screenshots 74 | fastlane/test_output 75 | fastlane/readme.md 76 | 77 | # Version control 78 | vcs.xml 79 | 80 | # lint 81 | lint/intermediates/ 82 | lint/generated/ 83 | lint/outputs/ 84 | lint/tmp/ 85 | # lint/reports/ 86 | -------------------------------------------------------------------------------- /.idea/$CACHE_FILE$: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | Android 10 | 11 | 12 | Chrome OSCorrectnessLintAndroid 13 | 14 | 15 | Code style issuesJava 16 | 17 | 18 | CorrectnessLintAndroid 19 | 20 | 21 | Declaration redundancyJava 22 | 23 | 24 | Java 25 | 26 | 27 | LintAndroid 28 | 29 | 30 | Probable bugsJava 31 | 32 | 33 | 34 | 35 | OptionalAssignedToNull 36 | 37 | 38 | 39 | 40 | 41 | -------------------------------------------------------------------------------- /.idea/codeStyles/Project.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | 7 | 8 | 9 |
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112 | 113 | 114 | 115 | 116 | -------------------------------------------------------------------------------- /.idea/misc.xml: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | -------------------------------------------------------------------------------- /CODE_OF_CONDUCT.md: -------------------------------------------------------------------------------- 1 | # Contributor Covenant Code of Conduct 2 | 3 | ## Our Pledge 4 | 5 | In the interest of fostering an open and welcoming environment, we as 6 | contributors and maintainers pledge to making participation in our project and 7 | our community a harassment-free experience for everyone, regardless of age, body 8 | size, disability, ethnicity, sex characteristics, gender identity and expression, 9 | level of experience, education, socio-economic status, nationality, personal 10 | appearance, race, religion, or sexual identity and orientation. 11 | 12 | ## Our Standards 13 | 14 | Examples of behavior that contributes to creating a positive environment 15 | include: 16 | 17 | * Using welcoming and inclusive language 18 | * Being respectful of differing viewpoints and experiences 19 | * Gracefully accepting constructive criticism 20 | * Focusing on what is best for the community 21 | * Showing empathy towards other community members 22 | 23 | Examples of unacceptable behavior by participants include: 24 | 25 | * The use of sexualized language or imagery and unwelcome sexual attention or 26 | advances 27 | * Trolling, insulting/derogatory comments, and personal or political attacks 28 | * Public or private harassment 29 | * Publishing others' private information, such as a physical or electronic 30 | address, without explicit permission 31 | * Other conduct which could reasonably be considered inappropriate in a 32 | professional setting 33 | 34 | ## Our Responsibilities 35 | 36 | Project maintainers are responsible for clarifying the standards of acceptable 37 | behavior and are expected to take appropriate and fair corrective action in 38 | response to any instances of unacceptable behavior. 39 | 40 | Project maintainers have the right and responsibility to remove, edit, or 41 | reject comments, commits, code, wiki edits, issues, and other contributions 42 | that are not aligned to this Code of Conduct, or to ban temporarily or 43 | permanently any contributor for other behaviors that they deem inappropriate, 44 | threatening, offensive, or harmful. 45 | 46 | ## Scope 47 | 48 | This Code of Conduct applies both within project spaces and in public spaces 49 | when an individual is representing the project or its community. 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Try and learn more deeply abut the concepts. For any particular questions, You can ask anytime. 10 | 11 | 12 | ## DS 13 | 14 | 1) https://www.geeksforgeeks.org/find-minimum-element-in-a-sorted-and-rotated-array/ 15 | 16 | 2) https://www.geeksforgeeks.org/largest-subarray-with-equal-number-of-0s-and-1s// 17 | 18 | 3) https://www.geeksforgeeks.org/find-triplets-array-whose-sum-equal-zero/ 19 | 20 | 4) https://www.geeksforgeeks.org/level-order-traversal-in-spiral-form/ 21 | 22 | 5) https://www.geeksforgeeks.org/construct-tree-from-given-inorder-and-preorder-traversal/ 23 | 24 | 6) https://www.geeksforgeeks.org/write-an-efficient-c-function-to-convert-a-tree-into-its-mirror-tree/ 25 | 26 | 7) https://www.geeksforgeeks.org/maximum-sum-such-that-no-two-elements-are-adjacent/ 27 | 28 | 8) [https://www.geeksforgeeks.org/longest-common-subarray-in-the-given-two-arrays/?ref=leftbar-rightbar](https://www.geeksforgeeks.org/longest-common-subarray-in-the-given-two-arrays/?ref=leftbar-rightbar) 29 | 30 | 9) [https://www.geeksforgeeks.org/maximum-sum-path-across-two-arrays/](https://www.geeksforgeeks.org/maximum-sum-path-across-two-arrays/) 31 | 32 | 10) [https://www.geeksforgeeks.org/merge-two-sorted-arrays-o1-extra-space/](https://www.geeksforgeeks.org/merge-two-sorted-arrays-o1-extra-space/) 33 | 34 | 11) [https://www.geeksforgeeks.org/segregate-0s-and-1s-in-an-array-by-traversing-array-once/](https://www.geeksforgeeks.org/segregate-0s-and-1s-in-an-array-by-traversing-array-once/) 35 | 36 | 12) [https://www.geeksforgeeks.org/construction-of-longest-monotonically-increasing-subsequence-n-log-n/](https://www.geeksforgeeks.org/construction-of-longest-monotonically-increasing-subsequence-n-log-n/) 37 | 38 | 13) [https://www.geeksforgeeks.org/kth-smallestlargest-element-unsorted-array/](https://www.geeksforgeeks.org/kth-smallestlargest-element-unsorted-array/) 39 | 40 | 14) [https://www.geeksforgeeks.org/find-zeroes-to-be-flipped-so-that-number-of-consecutive-1s-is-maximized/](https://www.geeksforgeeks.org/find-zeroes-to-be-flipped-so-that-number-of-consecutive-1s-is-maximized/) 41 | 42 | 15) [https://www.geeksforgeeks.org/reverse-a-doubly-linked-list/](https://www.geeksforgeeks.org/reverse-a-doubly-linked-list/) 43 | 44 | 16) [https://www.geeksforgeeks.org/longest-common-increasing-subsequence-lcs-lis/](https://www.geeksforgeeks.org/longest-common-increasing-subsequence-lcs-lis/) 45 | 46 | 17) [https://www.geeksforgeeks.org/fix-two-swapped-nodes-of-bst/](https://www.geeksforgeeks.org/fix-two-swapped-nodes-of-bst/) 47 | 48 | 18) [https://www.geeksforgeeks.org/backttracking-set-2-rat-in-a-maze/](https://www.geeksforgeeks.org/backttracking-set-2-rat-in-a-maze/) 49 | 50 | 19) [https://www.geeksforgeeks.org/detect-and-remove-loop-in-a-linked-list/](https://www.geeksforgeeks.org/detect-and-remove-loop-in-a-linked-list/) 51 | 52 | 20) [https://www.geeksforgeeks.org/find-minimum-element-in-a-sorted-and-rotated-array/](https://www.geeksforgeeks.org/find-minimum-element-in-a-sorted-and-rotated-array/) 53 | 54 | 21) [https://www.geeksforgeeks.org/maximum-product-subarray/](https://www.geeksforgeeks.org/maximum-product-subarray/) 55 | 56 | 22) [https://www.geeksforgeeks.org/merge-k-sorted-arrays/](https://www.geeksforgeeks.org/merge-k-sorted-arrays/) 57 | 58 | 23) [https://www.geeksforgeeks.org/sort-an-array-of-0s-1s-and-2s/](https://www.geeksforgeeks.org/sort-an-array-of-0s-1s-and-2s/) 59 | 60 | 24) [https://www.geeksforgeeks.org/a-product-array-puzzle/](https://www.geeksforgeeks.org/a-product-array-puzzle/) 61 | 62 | 25) [https://www.geeksforgeeks.org/count-frequencies-elements-array-o1-extra-space-time/](https://www.geeksforgeeks.org/count-frequencies-elements-array-o1-extra-space-time/) 63 | 64 | 26) [https://www.geeksforgeeks.org/median-of-two-sorted-arrays-of-different-sizes/](https://www.geeksforgeeks.org/median-of-two-sorted-arrays-of-different-sizes/) 65 | 66 | 27) [https://www.geeksforgeeks.org/find-maximum-path-sum-in-a-binary-tree/](https://www.geeksforgeeks.org/find-maximum-path-sum-in-a-binary-tree/) 67 | 68 | 28) [https://www.geeksforgeeks.org/lowest-common-ancestor-in-a-binary-search-tree/](https://www.geeksforgeeks.org/lowest-common-ancestor-in-a-binary-search-tree/) 69 | 70 | 29) [https://www.geeksforgeeks.org/lowest-common-ancestor-binary-tree-set-1](https://www.geeksforgeeks.org/lowest-common-ancestor-binary-tree-set-1) 71 | 72 | 30) [https://www.geeksforgeeks.org/sorted-linked-list-to-balanced-bst/](https://www.geeksforgeeks.org/sorted-linked-list-to-balanced-bst/) 73 | 74 | 31) [https://www.geeksforgeeks.org/given-an-array-a-and-a-number-x-check-for-pair-in-a-with-sum-as-x/](https://www.geeksforgeeks.org/given-an-array-a-and-a-number-x-check-for-pair-in-a-with-sum-as-x/) 75 | 76 | 32) [https://www.educative.io/edpresso/how-to-find-the-most-frequent-word-in-an-array-of-strings](https://www.educative.io/edpresso/how-to-find-the-most-frequent-word-in-an-array-of-strings) 77 | 78 | 33) Continuation Question to `32`, What is the time complexity of your solution and how can you improve it? 79 | 80 | 34) What is the time complexity of mergeSort, quickSort and Binary search? 81 | 82 | 35) What is the time complexity for removing an element from LinkedList? 83 | 84 | ## Java 85 | 86 | * Interfaces vs Abstract Classes.Why Interfaces if abstract classes are already there. 87 | 88 | * JAVA 8 new features 89 | 90 | * Hashmap implementation,ArrayList implementation 91 | 92 | * How to make a class immutable. 93 | 94 | * String pools,intern keyword,new() keyword 95 | 96 | * Linked list vs Array,Array vs ArrayList,Set vs List vs Map,Iterator vs Enumeration. 97 | 98 | * How to compare two objects in Set?(hint : equals() and hashcode() overriding) 99 | 100 | * How ClickListener implemented in Java? 101 | 102 | * Programs based on Inheritance and multithreading. (Most Important) 103 | 104 | * 1.) Add(String string) 2.) Add (Object object), you called Add(null) what will be the output here? 105 | 106 | * Why main Static? 107 | 108 | * Static vs Singleton? Which to prefer when? 109 | 110 | * Can a static method be overloaded/overridden?Can a constructor be made static? Can we override/overload constructor? Which type of error you get-Compile/Runtime. 111 | 112 | * Can we have final/static/default methods in interface/abstract classes? 113 | 114 | * Check for every keyword? Which type of error-Compile time or runtime(I remember it after I tried a sample in Android studio). 115 | 116 | * Stack vs Heap allocation in Java. 117 | 118 | * Why is String immutable? 119 | 120 | * Why reflection in Java?Introspection vs Reflection? 121 | 122 | * Anonymous vs Inner Classes.Static Inner Classes. Can we have Static inner classes on Top? 123 | 124 | * What is the naming structure for an inner class in java? 125 | 126 | * Default value for Access specifiers,primitie types. 127 | 128 | * Protected vs Default. Do static retain value if an application is removed from recent. 129 | 130 | * How is the Exception class implemented in java?Try/Catch with finally block. 131 | 132 | * Any situation when finally won’t get executed? 133 | 134 | * Is Java pass by value/reference? 135 | 136 | * What will be the result if StringBuffer value compared with String — strbuf.equals(str) /str.equals(strbuf) 137 | 138 | * Synchronization in Java. 139 | 140 | * Can one interface extend/implement other/Can one abstract class extend other? Can interface extend abstract classes? 141 | 142 | * Runtime vs compile time polymorphism with real-world scenarios. How do you define encapsulation? 143 | 144 | * this vs super() keyword 145 | 146 | * Implement own Garbage collection in java. 147 | 148 | * Why runnable interface if we have already had Thread class in Java? 149 | 150 | * Why thread pool in Java? 151 | 152 | * Order of call of constructors during Inheritance. 153 | 154 | ## Kotlin 155 | 156 | * Why should we use Kotlin for Android Development? 157 | 158 | * Kotlin operators - apply, run, let, ? 159 | 160 | * How Kotlin is null-safe? 161 | 162 | * What is the difference between var and val? 163 | 164 | * How const is different from val? 165 | 166 | * What is the difference between ?. and !! 167 | 168 | * How to define static functions in Kotlin? 169 | 170 | * What are Data Classes in Kotlin? 171 | 172 | * What do you mean by Sealed classes in Kotlin? 173 | 174 | * Collections in Kotlin. 175 | 176 | * Difference between lateinit and lazy. 177 | 178 | * What is Kotlin synthetic binding? 179 | 180 | * Difference between Kotlin Synthetics, View binding and Butterknife? 181 | 182 | * What are extension functions in Kotlin? 183 | 184 | * What are lambda expressions? 185 | 186 | * What are Higher-Order functions in Kotlin? 187 | 188 | * Difference between let, run, with, also, apply in Kotlin. 189 | 190 | * What is the best way for performing tasks on a background thread in kotlin? 191 | 192 | * What are Coroutines in Kotlin? 193 | 194 | * What are the different Coroutines Scope? 195 | 196 | * Why use suspend function in Kotlin Coroutines? 197 | 198 | * Explain Coroutine LifecycleScope. 199 | 200 | * What is Kotlin Flow? 201 | 202 | * Kotlin Flow vs RxJava. 203 | 204 | * Room vs Realm? Why not Realm? 205 | 206 | 207 | ## Android 208 | 209 | (Also they ask for code not just theory things. Keep this in mind.) 210 | 211 | * Activity/Fragment/Broadcast/Application/Service Lifecycle (Explain with one line description) 212 | 213 | * Which lifecycle method gets called when A goes to B/come back to A?
Activity Launch Modes with examples 214 | 215 | * Let’s say 4 activities are there A->B->C->D. How to launch A from D finishing in between activities? 216 | 217 | * 4 Activities are there A->B->C->D.How to finish application from D if none of the activities opened earlier finished till now? 218 | 219 | * How CLEAR_TOP flag intent works in android? 220 | 221 | * Service vs IntentService?When to prefer which type of service? 222 | 223 | * Explain ways for Activity to activity communication/Activity to fragment communication/Fragment to fragment communication. 224 | 225 | * How to make a service persist even after Application killed? 226 | 227 | * How to achieve Interprocess communication in android? 228 | 229 | * How Async task internally works? Async task implementation? 230 | 231 | * Cons of using Async task? How to overcome this limitation? 232 | 233 | * Why Job Scheduler? 234 | 235 | * Notification related changes in Oreo? 236 | 237 | * How to handle Background service and execution limits with new Oreo Updates? 238 | 239 | * Have you seen Google I/O 2018? What were the updates for Android there? 240 | 241 | * Why do we use Headless fragments? 242 | 243 | * Memory Leakage, Causes, and preventions in Android? I have written a blog out here.You can refer [this too](https://medium.com/@nik.arora8059/memory-management-in-android-3bdf307c8e23) 244 | 245 | * Ways to optimize an Android Application. 246 | 247 | * Proguard-Obfuscation/ Minification, Build Variants, Flavours. 248 | 249 | * How to achieve MultiThreading in Android? 250 | 251 | * Suppose you have 10 images to fetch from Server. What is the best way to fetch images? (Hint: Read about ThreadPool and Executor) 252 | 253 | * Builder vs Factory Pattern with an example 254 | 255 | * Why MVP not MVC? They will ask you to make a wireframe kind of thing on paper to demonstrate MVP pattern in android. 256 | 257 | * Why RXJAVA so popular nowadays? 258 | 259 | * Problems in RXJAVA? They can provide you with some scenarios to get to know if you can find out the problems with it. 260 | 261 | * Map vs Flat map? (Most commonly asked in RXJAVA) 262 | 263 | * Should we provide a context in presenter/Model? Answering yes/no is not enough. You have to provide a solution for it. 264 | 265 | * Why Schedulers and How Rxjava internally works with them?
SusbcribeOn vs ObserveOn, Schedulers on which both of these work?
.subscribe(new Subscriber…) vs .subscribe(new Observer…) 266 | 267 | * IOScheduler/new Thread Scheduler in RXJava 268 | 269 | * How dagger internally worksDagger vs Dagger2? Explain the purpose of every annotation taken in Dagger2. 270 | 271 | * How do you decide scope in Dagger? Why Qualifier annotation? 272 | 273 | * Why do we use Handlers? Do you know the Loopers? What’s the role of Message queue? With this, they will go for Main Thread working. They will also ask you about the exceptions we get as Looper.prepare() exceptions 274 | 275 | * Cause of Memory leak during the Async Task? 276 | 277 | * Explain Singleton pattern. Problems with it and Handling. (hint: Double checked locking/synchronization) 278 | 279 | * Why do you prefer Retrofit over Volley? Why Picasso? Now they will ask all the third party libraries you have used. Be honest with your answer. They may go deep in any of those. 280 | 281 | * Why ConstraintLayout?Barriers vs Guidelines, Why Group/Chains? 282 | 283 | * Why do we prefer Framelayout for Fragments? 284 | 285 | * Why ANR?How to prevent it? 286 | 287 | * Do async.execute make threads in parallel or serial? 288 | 289 | * How to make a custom view in android? Explain lifecycle methods. Difference between onLayout/onMeasure. 290 | 291 | * Have you ever faced any issue with SingleInstance launch mode or example if you have used it? Providing real-life examples are preferred more. 292 | 293 | * When 1 fragment added over another-Explain lifecycle methods. Another question would be if you replace instead of adding it. The 3rd question will be if you have back stack there. 294 | 295 | * Why fragment newInstance() is there (Best practice for instantiating a new Android Fragment) 296 | 297 | * Suppose you have to update location every minute even if you don’t get permission. But the tricky thing here is how will you notify the server-Through the same service you were sending updates using FusedLocationProvider/Will you use some other service or broadcast. Just design the whole thing. 298 | 299 | * Observable.just/Observable.from/Observable.create in RXJAVA? 300 | 301 | * Why Instant Apps? How do you achieve this? 302 | 303 | * How to load Large Bitmaps? Handle Memory leaks and Sample sizing 304 | 305 | * How parcelable internally works? Design it. 306 | 307 | * What happens if your serializable class contains a member which is not serializable? How to handle it? 308 | 309 | * Why do we use WeakReferences? 310 | 311 | * How to retain data on orientation change? Explain lifecycle during orientation changes. 312 | 313 | * How to make endless circular recyclerView? 314 | 315 | * Suppose you have given an array of array of custom Objects. Which data structure will you use to show these on UI? 316 | 317 | * How do you handle opening activity using notifications? 318 | 319 | * How to achieve Push notifications in android? Explain behavior during App in front/Background-How to handle both scenarios. 320 | 321 | * How to download files in parallel? 322 | 323 | * Why Realm?Realm Methods, Realm vs Sqlite. 324 | 325 | * How to handle different screen sizes/density/languages/orientation in android? 326 | 327 | * What the Fragment’s method setRetainInstance(boolean) does? 328 | 329 | * Keep yourself up to date with the latest library versions if using. 330 | 331 | * Why is there a need for JobIntentService?(hint:: Oreo update) 332 | 333 | * Basics for Testing in Android-They will ask some questions about Espresso,mockito,roboelectric(not in that deep).Stub vs mock. Also if you are following MVP pattern. Be prepared for the questions now. 334 | 335 | * How the OS handles process flow. When is the app killed or removed from recent memory? How OS decides this. 336 | 337 | * Which method gets called when home button pressed, back pressed etc.(Most commonly asked) 338 | 339 | * Manifest related attributes -allowBackup,intent-filters,process,taskAffinity,permission vs uses-permission etc. 340 | 341 | * Draw a simple basic design you follow to make an android application(folder structure, methods, variables) 342 | 343 | * Why services preferred over Broadcast receiver for background applications 344 | 345 | * Broadcast-related changes in Oreo and Handling them. 346 | 347 | * Accessibility services in android. How do you handle system apps(I mentioned this work too, so asked) 348 | 349 | * Thread.start() vs run method,submit vs Execute ,callable vs runnable 350 | 351 | * View Holder pattern.ListView vs RecyclerView. 352 | 353 | * Remote Views and How to use them? 354 | 355 | * Inner Classes vs Static Classes? 356 | 357 | * Volatile vs Transient 358 | 359 | * Internal Implementation of Picasso, Glide 360 | 361 | * Internal implementation of Recyclerview 362 | 363 | * Design Patterns and Practical Usage 364 | 365 | * Custom View and Lifecycle 366 | 367 | * Singleton vs Static and why we use them? 368 | 369 | * Deep vs Dynamic Linking 370 | 371 | * Livedata postValue vs set 372 | 373 | * Livedata vs ObservableField 374 | 375 | * ViewModelFactory 376 | 377 | * HashCode and Equals Implementation 378 | 379 | * Dagger - Component vs SubComponenets 380 | 381 | * TDD and frameworks - if using , tell the challenges faced 382 | 383 | * GSON vs Jackson vs Moshi 384 | 385 | * MultiModule Benfeits 386 | 387 | * Android Bundle - and Dynamic Feature usage 388 | 389 | * Proguard vs R8 390 | 391 | * What is Scoped Storage and how to implement? 392 | 393 | * Observable vs Completable vs Single 394 | 395 | * Rx vs Coroutines. Which one you prefer and when? 396 | 397 | * Difference between MVP and MVVM? 398 | 399 | * Explain SOLID principles? 400 | 401 | * Difference between const and val 402 | 403 | * When is onPause() called without onStop() being called? 404 | 405 | * Dagger vs Koin? 406 | 407 | * Any 5 RxJava operatrs. How subscribeOn and observeOn works? 408 | 409 | * Headless Fragments. 410 | 411 | * Workmanager, type of requests, methods, minimum interval before a job repeat itself. 412 | 413 | * Workmanager vs JobScheduler. 414 | 415 | * Why ConstraintLayout? Tell some properties which I find worth. 416 | 417 | * How SharedPreferences work internally? 418 | 419 | 420 | >You will be given assignments as your first/last round. They just want to know how you follow the standards. Some ask for UI thing, other ask for architectural patterns. Just check your methods and play well with the logic.That’s all. 421 | 422 | ## System Design 423 | 424 | * Design Whatsapp/Chat application/Facebook messenger. 425 | 426 | * Implement search functionality with debounce operator (If user keeps on typing, then cancel the last network call and hit for the present one, How will you achieve that?) 427 | 428 | * Design a Location Tracking application 429 | 430 | * Design Uber/Ola. 431 | 432 | * Design Twitter. 433 | 434 | * Design Bookmyshow. 435 | 436 | ### That’s all Guys. The moment I come out of the interview room, I always note down the questions on Google Keep. Blogs & Github links helped me so much in cracking these interviews. See Now I can help others too -:) 437 | 438 | If you learn about the concepts for the above questions, I am sure you will get your basics strong and with the strong basics, you can easily crack any interview. 439 | 440 | I have written an [article](https://blog.usejournal.com/interview-questions-for-android-java-ds-f5081cb3aa09) on the same. 441 | 442 | If you have more questions, I will be happy to learn, add & share. Please raise a [PR](https://github.com/niharika2810/android-interview-questions/compare) and contribute. :-) 443 | 444 | 445 | 446 | 447 | -------------------------------------------------------------------------------- /images/interview.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/niharika2810/android-interview-questions/aba449d373b3f95f42d9204e12013166545483c0/images/interview.png --------------------------------------------------------------------------------