Top 100 Flutter Interview Questions

hello guys and welcome to this video in this video we will discuss about top 100 L interview questions that probably chance to ask by interviewer so as you know that letter is a great open source software development get that is developed by Google so in this video we will discuss some of the major questions that probably chance that asked by interviewer so we side providing you with an idea of flutter interview question we will also give you tips by is of flutter interv so in this thing uh it is great to help you whether you are a candidate looking for an interviewer and also for our recruiting so let's start with some of the simple questions after that we will deep inside things so first question is what is flutter so flutter is a open source framework which is a developed by Google and basically by flutter we can make beautiful UI also it is natively compiled as well and uh main thing is that flutter provide multiplatform application for a single code base also flutter is not a language it's a Ed sticking and flutter app use do programming language for creating a app and uh First Alpha version of letter release in May 2017 so second question is what is dot so dot is a open-source programming language developed by Google in 2011 the purpose of dot programming is to create front end user interface for web and mobile apps do is a client optimized language for developing fast app on any platform and its main goal is to offer most productive programming language for multiplatform a development so third question is what are the flutter vets so answer is flutter vet are build using a modern framework that take inspiration from react the central idea is to that build from your UI of wigets uh we can say described that their view should look like given their current configuration in state also when State changes the vetry will this description so which is the framework defer again the previous description to determine the minimal changes needed in underlying render tree to transform from one state to next state so fourth question is what is the difference between stat less and stateful viset in flutter so a stly fidget is useful when a part of user interface you describe does not depend on anything other than configuration informations also in the build context whereas stateful widget is useful when the part of user interface you are describing can change dynamically uh stateful wiet is mutable widget that is the reason it can be draw multiple times within its lifetime also it is referred as to dynamic because it can change the inner data during wiet life cycle uh viset that allowed us to refresh the screen is called stateful viset this wiget is create State method which return a class that extend the flutter State class example of State full visit are checkbox radio slider inil font and text bu and a state L widget will never rebuild by itself but can be do some from external event uh a stat L vet does not have any other state informations it remains static throughout its life cycle example of stateless wiget are text row column container Etc so if the screen or viset contain State contain it should be a stat less wiet however if you want to change its content it need to be a stateful wiget so so fth question is what is stateful wiget life cycle so the life cycle of stateful fidget has simplified in mainly seven steps so first is create state so it's called when we build a new State full wiet this one called create State method right away and this overr right method must exist second is init state so it is the first method called after viset is created this is our equivalent to on Create and view load method third is dat chain dependency so this method is called immediately of in it State method on the first time when visit is BU so for this build method this is called right after ditch independency all the GUI render here and will be able called every single time the UI is needed to be rendered then did update wiet called which it is will be called once of our parent V and did change and need to be redraw the UI then deactivate is called so it framework called this method whenever it remove this state from the object from the tree then this fourth method is there so it is called when the object and its state are removed from the tree permanently and will never build again sixth question is what is AP life cycle state so applying cycle is following steps first is inactive so this called when the application is in a inactive State and it is not receive user input this called only in iOS then post is called so this called when the application is not currently visible to the user and not responding to user input and running in a background then third one is resumed so this call when the application is visible and responding to the user input then fourth one is suspending so when the application is will suspend it moment this called and it's only called in Android the seventh question is what is pubp yml file so pubp yml file is responsible for handling importing data in your flut application something like you can import images on third party packages by in this file so this file is used to find the dependency of your FL project as well we can say that this is a metadata information is written in the vml language also this file can have the following fields which is a name version description repository documentation dependency environments Etc so eth question is what is the difference between flutter package and flutter plug-in so in a short answer we can say that a package contain only do code and plug-in contain V Dot and native code we can say in native code there is scotl Javascript sft code but uh in a description way we can say that flutter plug-in is basically for Native development and uh flutter plugin is a rer of the native code like Android for C in Java and for iOS there is sft 10 objectiv C and uh letter can do anything that a native application can through the use of this by internally we can use platform Channel and message passing also it instruct the native is and Android code to a return do dot code and uh platter Plage or module we can say that uh it's making for development Faster by using this code in your C libraries just like uh it supported to using shared page and contributed by other developers to use flut and. ecosystem more efficient uh it is like this allow for quickly building for your app without having to develop everything from scratch so ninth one is what is the difference between V tap and material app so vget app is basically a convincing class that bre several wigets that are commonly required for applications one of the primary role for a wiet tape is providing a binding into the system from the big button to pop from the navigation or creating the application and uh material app is a convenience viset that rep server wigets that are commonly required for material design in application and it's built upon to vet T by adding material design or a speciic functionability such as animated triam and great paper so 10th one is what is the difference with between hard load and hard start feature so in simple word hard load is just updating the changes in your program but H restart will again remove your previous state and run the complete program so if we talk about in our description so Hardo is a feature that better hard load work with combination of small R key and command from from the terminal the hard reload feature quickly compile the native edit code in your file and send code to do virtual machine after done updating the code do virtual machine updating API with the widget uh H load take L time then hyart then another thing is there is also drawback in h load if you are using state in your application then H reload reserve the state so they will not updating on H reload our set of their default value in terms of H start so hot restart is much different from Hot Load in hot Lo hot restart it destroy the preserved State value and set them to their default value so so if you are using State value in your application then after every Haun restart the developer gets a fully compiled application and all of the state will be set to their default value and in hard restart the a fidget tree is completely rebuilt with the new type of code also we not restart take much higher time than not reload so 11th question is can you n ask SK fold widget so yes you can n a scap fold wiget that's the beauty of letter you can control all over the UI in your application and esape fold is just a wiget you can put it anywhere in a widget tree that you want to buy a nesting of this you can create any layer of drawer snake bar bottom sheet or inher so 12th question is describe some of the major feature of flutter so major feature of flutter is their fast development expressive and flexible UI and it provide native performance fast development is something like with this we can use a re set of fully customizable viset you can build native interface in a m minute with sweater expensive and flexible U tends that up then layered architecture in with the flutter enable you to fully customizable to your API this result in Faster rendering and expressive design and in terms of native performance so the viset present in the flutter incorporate all about the critical platform different such as scrolling Navigation icon and more so it gives you fully native performance on all the platforms 13 question is how do you reduce vet rebuild so you can rebuild viset when the state change this are normal and desirable because it allow the the user to see the state changes reflected in the UI however rebuilding part of the UI that does not need to change its wasteful there are several things that you can do to reduce unnecessary vet Tre welding first thing is that uh you can deflector large vet tree into smaller for indivual wigets each with the build method second point is whenever possible use the cons Constructor because this is f till first letter that it doesn't need to rebuild the widget and third point is we can say we can keep the sub tree of stateful wiet as small as possible if stateful wiet need to have a wiget sube under it then create a custom wiet for state full wiget and give is to channel parameter so 14th question is what is build context and how it is useful so build context is the wigets element in the elementary so every wiget has own build context you can use clean use build context to get reference to the theme or another wiet for example if you want to show a material dialogue you need to refresh RS to the skip fold diget uh you can create it with the skip fold do off context where context is the build context of of method search up to the three until it find the nearest scap fold visit 15th question is how do you talk to native code from within a flut so in normally you don't need to talk to native code because the flutter frame work or third party plugin can handle it easily however if you do find yourself needing to get special access to the underlying platform you can use platform channel one type of platform channel is Method channel so by Method Channel data is cized on the that site and then send to the native site you can write native code to interact with the platform before sending a civiliz message back that message might be written in Java or ctin or Android and Objective C or sft for iOS you don't use platform channel on the P however because they are an unnecessary step the second type of platform channel is the channel so by Event Channel you use to send a stream data from the Native platform back to the flutter code this is useful for monitoring sensor data so 16th question is what type of test you are performing in flutter so there are many type of test you can perform in flutter but three are the main which is a unit test vet test and interation test so by the unit test is useful for all about to checking the validity of your business Logic for the viset test are useful for making sure that your UI viset have that component you expected are working and in integation test you can check that your app is working fine in your wallover so 17th question is what are the pron and cons of different State Management Solutions so when there are countless varieties of this thing some of the most popular state mment Solutions are block genin Notifier with provider Redux MX RX dot or gex and also for the rerp so these all are appropriate for medium to large scale applications so if you are only making a quick demo then stateful Vis is often enough so instead of listening pron and SC of this state man menu option it is more useful to look at the situation where a certain class of solution is a better enough so for example if someone's Voice or with SE number options so it is important to choose solutions that easy to grap mentally so if you are a heavy CL of stream just like a fireb and basically if your application is stream B so I think you choose block and uh or smaller application I think uh rerp is well enough and uh it is also for your opinion that which state mement you are fit for your project so 18th question is what is stream INF flutter so stream is a sequence of a synchronous event which is provide a SE sequence of data it is the same is like P where we put some value on the one end and if we have listen on the other end it will receive that value so we can keep multiple listener and this stream and all of those will receive at the same value when we put in to this pipeline so 19th question is how to create private variable in dot so in a DOT underscore is used before the variable name to declare it's a private unlike other programming languages so here private doesn't mean it is available only to the class in it private means it is a accessing in the file and it is not accessing to other file so 20th question is what is the event Loop and what its relationship to isolates so in flutter the event Loop is the central concept that help manage to flow of control within the H so it is responsible for processing event and updating AP state in response do event an isolates is a separate dat threat of execution that it's isolated from the main thread of the so isolates are used in flutter to allow concurrency execution of code which can be useful for task that might take a long time for completing such as for Network request or computationally intensive operations so the event Loop is related to the isolate in that it is responsible for coordinating the execution of code across multiple isolates if they are used in the app so it does this the Sending message between isolate and scheduling the execution of code on the appropriate isolates so overall the event Loop play a crucial role in the operation of FL rep also helping to manage the flow of control and coordinate the execution of cod across multiple isolates so 21 question is what is the tree shaking INF flutter so tree shaking is an optimization technique to remove the unused module in the bundle during the build process it is also a date code elimination technique to use in the optimization for code so 22 question is what is De tool INF flutter so de tool INF flutter are the set of tools used to perform min's management and for debugging so with this tool you can inspect the UI layout diagnose the UI performance issue also perform sourcing level deing and view General log and diagnostic information and lot of more things so our 23 question is what is the flex wiet INF flutter so the flex wiet allows you to control the axis along which The Childrens are placed in horizontal or vertical this is a refers as to the main AIS if you know the main AIS in advance then consider using the row if it's horizontal or column if it's vertical instead because that will be less ver us so 24th question is what is the difference between expanded and flexible vets so flexible is used to resize the vets in rows and column it's mainly used to adjust the space of the different child's widgets while keeping the relation within their parent viset meanwhile expanded changes the constraint sent to the children's of rows and column it helps to F the level space there so when you are R your child in expanded viset it fill up the empty space so our 25th question is what is the difference between Matan versus Cino wigets so cartino wigets are used to build an iOS like app and material is used to build an Android material we can say that capertino visits implement the current I design language based on Apple human interface guideline and in terms of matal wiget materal wiget implement the material design language for iOS Android we and desktop and also the material design language was was created for any platform not just for Android when you write a material app in flutter it is the material look and F on all devices even for IOS as well so if you want to your app look like standard on is Style app you can choose catino instead of material fidgets so that's a wrap up for part one of our series which we highlighted 25 questions in this segment we will delete into a top 100 FR questions so join us in the next video where we will take next 25 questions in this line so thanks for watching have a good day

Channel: CodingMiles

Views: 695

Keywords: flutter, dart, top 100 flutter interview questions, flutter interview question answers, flutter interview questions, flutter interview questions and answers, flutter interview

Id: pQL0R7Opa7M

Length: 26min 47sec (1607 seconds)

Published: Sun Feb 11 2024