投稿時間:2023-04-17 01:11:05 RSSフィード2023-04-17 01:00 分まとめ(15件)

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IT	気になる、記になる…	Apple、｢MacStudio｣の後継モデルを開発中	https://taisy0.com/2023/04/17/170717.html	apple	2023-04-16 15:08:03
python	Pythonタグが付けられた新着投稿 - Qiita	【2023年4月決定版】Stable Diffusion 公式にはないモデルを使ってフォトリアリスティックな美女画像を作る	https://qiita.com/javacommons/items/77f520d531eaed85ed53	stablediffusion	2023-04-17 00:56:53
python	Pythonタグが付けられた新着投稿 - Qiita	lightgbmで多クラス分類を試す	https://qiita.com/S_Satou/items/d4fd2e020da2c68a87ba	lightgbm	2023-04-17 00:33:14
python	Pythonタグが付けられた新着投稿 - Qiita	Chat GPTをPythonから呼び出すプログラム（API)	https://qiita.com/ykoji/items/608d0362ec4d00d73122	apikey	2023-04-17 00:14:15
js	JavaScriptタグが付けられた新着投稿 - Qiita	【Vue.js & Three.js】WARNING: export 'Math' (imported as 'THREE') was not found in 'three' の対処法	https://qiita.com/ysenkun/items/073f991ad2cb1638e9bd		2023-04-17 00:04:09
AWS	AWSタグが付けられた新着投稿 - Qiita	webアプリ「EChub」を作ってみた【FastAPI/React/AWS/Vercel/Docker/スクレイピング】	https://qiita.com/cowki1999/items/0ae7d4292a90d7ff0a04	tapireactawsverceldocker	2023-04-17 00:12:05
Docker	dockerタグが付けられた新着投稿 - Qiita	webアプリ「EChub」を作ってみた【FastAPI/React/AWS/Vercel/Docker/スクレイピング】	https://qiita.com/cowki1999/items/0ae7d4292a90d7ff0a04	tapireactawsverceldocker	2023-04-17 00:12:05
Git	Gitタグが付けられた新着投稿 - Qiita	GitHubハンズオン 第3回 ～ブランチ運用法編～	https://qiita.com/segur/items/1dd578003da46bddc117	github	2023-04-17 00:18:38
海外TECH	DEV Community	How To Use MVVM in React Using Hooks and TypeScript	https://dev.to/perssondennis/how-to-use-mvvm-in-react-using-hooks-and-typescript-3o4m	How To Use MVVM in React Using Hooks and TypeScriptSoftware applications often start out simple and quickly grows big No matter how small one try to keep it the code somehow always grows up to be a full fledged application In many languages we follow structural patterns as MVVM and Clean Architecture which is less common to see in the Wild West Web In this article we will take a look at how a React application can be designed to follow the MVVM architectural design pattern to create a React application that is both scalable and maintainable We will use TypeScript and functional React components and write custom hooks for the ViewModel and Model The same code will of course work with React Native with some minor modifications If you have some questions while reading the article you have an extensive FAQ at the end of the article In This ArticleMVVM OverviewApplication OverviewView ImplementationViewModel ImplementationModel ImplementationFAQ MVVM OverviewIf you don t know what MVVM is you can either google it or read along anyway You should be able to follow along in the article either way In short MVVM is a design pattern that provides a clear separation of concerns making it easier to develop test and maintain software applications What MVVM does is to separate an application into Views ViewModels and Models Where the Views are responsible for presenting data to the user and capturing user input the ViewModels act as a mediator between the Views and the Models and the Models manage the application data Some people say architecture matters Application OverviewThe app we will build in this article is the tiny one you can see down here It s kept small so we can focus on the MVVM architecture The app consists of a single View listing articles with an input field for adding a new article with a given name The app to be built a single View to keep it simpleCodewise the application consists of one React component for the articles View then a few hooks for the ViewController ViewModel and Model Below is a architectural diagram of the code we will go through Disregard the ViewController for now which isn t an official part of MVVM we will discuss that one later Overview of the React components for the application in this articleA single View is of course not enough for a useful application If the example would be larger each View would have its own ViewController as depicted in the diagram below All ViewControllers that work against the same Model would use a common ViewModel What the application would look like with more viewsWhen the application grows even more it can include more Models and ViewModels I think you get that Anyhow let us start looking at the implementation for the app View ImplementationA View in the application can be any screen or visual component on the screen If the site to be built is a blog platform we could have screens for listing articles viewing a single article and for writing a new article Those screens could be implemented with in Views like ArticlesView ArticleView and CreateArticleViewThe View is responsible for displaying the UI and trigger actions based on user interactions Although there traditionally isn t a ViewController in MVVM this MVVM guide has split the View part of MVVM into two parts a View and a ViewController where the only responsibility of the View component is to render the UI while the ViewController handles all the logic for the View View ComponentAs we saw before the View will will look something like this with some CSS ArticlesView componentTo implement the View we use a regular functional React component that renders a UI To avoid handling view logic in the View component we use a ViewController which exports functions for all possible user actions view article articles view ArticlesView tsximport React from react import useArticlesViewController from view article articles view useArticlesViewController const ArticlesView React FC gt const articleName articles navigateToArticle onArticleNameChange onCreateArticleClick useArticlesViewController return lt div gt articles amp amp articles map id title gt lt div key id onClick gt navigateToArticle id gt title lt div gt lt div gt lt input type text onChange onArticleNameChange value articleName placeholder Add an article gt lt button onClick onCreateArticleClick gt Create article lt button gt lt div gt lt div gt export default ArticlesViewThe ArticlesView component above renders a view with articles When the user interacts with the UI this View component will simply forwards the action to a function in the useArticlesViewController hook Since this file only contains pure UI components and only reacts to user interactions by forwarding them to a hook it s very trivial to test and read The unit tests for this component would merely be to test that all articles are rendered and that the functions exported from the useArticlesViewController are called The useArticlesViewController itself would preferably be mocked since we will test that hook separately To test interactions with the view I would recommend interactional testing frameworks like React Testing Library You can read more about the benefits and how that compares to code based unit testing in my other article about unit testingI won t bother you with the CSS ViewController HookThe ViewController hook used in the View component handles the view logic for that View Each View component has its own ViewController hook There are several types of view logic in the ViewController View logic that updates the View components internal state typically useState useReducer or useRef View logic that updates the application s state e g navigating to other screens View logic that interacts with the ViewModelIn general the View logic is responsible for managing the user interface and handling user interactions This includes maintaining the component s internal state as well as handling conditions for interacting with the ViewModel By keeping all this kind of view logic in the ViewController we don t need any view logic in the ViewModel view article articles view useArticlesViewController tsximport useCallback useEffect useState from react import useHistory from react router dom import HOME SCREEN ROOM SCREEN from routing screens import useArticleViewModel from viewmodel useArticleViewModel const useArticlesViewController gt const history useHistory const articleName setArticleName useState const articles createArticle getArticles useArticleViewModel const onCreateArticleClick useCallback async gt await createArticle name articleName createArticle articleName const navigateToArticle useCallback articleId number gt history push ROOM SCREEN articleId history useEffect gt getArticles getArticles return articleName articles navigateToHome navigateToArticle onCreateArticleClick onArticleNameChange setArticleName export default useArticlesViewControlleruseArticlesViewController is a little more complex than its corresponding View component It contains code for navigation among screens using React Router It also keeps the internal state of the view which can be used for both handling internal logical conditions or to be passed back to the View component to be used in rendering Lastly we use a useArticleViewModel hook which is the ViewModel that this View uses Only the functions required to be used in this View needs to be destructured from that ViewModel This file includes more logic to test than the View component The good thing is that there s no need to test any UI elements at all You can test the hook purely using React Hooks Testing Library there s no need to use any UI element matchers or to check if data is rendered Simply invoke the functions returned from the hook and assert the expected outcome React Anti Patterns and Best Practices Do s and Don ts Dennis Persson・Feb ・ min read react javascript webdev programming ViewModel ImplementationThe ViewModel is responsible for handling the interactions between the View and the Model serving as a bridge between them Normally the View interacts directly with the ViewModel but as we already have seen we have split the View into a View component and a ViewController This means the ViewController is the one which uses the ViewModel The ViewModel is just as the ViewController implemented as a hook It doesn t include very much code in our Article example This is because our application example simply doesn t have any business logic But if we would have it we would have put it here viewmodel useArticleViewModel tsximport useArticleModel from model useArticleModel const useArticleViewModel gt const article articles createArticle getArticles useArticleModel return article articles createArticle getArticles export default useArticleViewModelYeah that s it It only wraps the functions in the useArticleModel hook by re exporting them If some of those actions would have required any business logic we would have created a wrapper function to perform the expected calculations within this hook What about testing Well when looking at this I would argue there s no need to test this file With more logic you can use React Hooks Testing Library here as well I didn t use to think testing is important but somehow I changed my mind Model ImplementationThe model is responsible for getting data from data sources and serving it to the ViewModel The ViewModel in turn uses the Model to fetch and modify the data The model can be written in a plenty of ways Redux Apollo hooks like useSWR and so on can all be used Furthermore there may not only be a single data source complex applications can fetch data from several different sources In that case it can be a good idea to put a repository in between the ViewModel and the Model Repositories are not a part of MVVM design pattern and will therefore not be used here Because the implementation of the model can vary significantly between projects this guide will not delve deeply into how to implement it Instead we will provide a simple example that makes use of REST API functions for retrieving and posting articles model useArticleModel tsximport useCallback useState from react import getAllArticles postArticle from model api article import ArticleDTO CreateArticleDTO from model api article const useArticleModel gt const articlesData setArticlesData useState lt ArticleDTO null gt null const getArticles useCallback async gt const articles await getAllArticles setArticlesData articles const createArticle useCallback async createData CreateArticleDTO gt if Array isArray articlesData const response await postArticle createData if response null setArticlesData articlesData id response id name response name articlesData return articles articlesData createArticle getArticles export default useArticleModelAs you can see there s more logic in this one Still we have kept it brief The logic is not very smart or robust but we can see that we have basic functionality for fetching and creating articles The code should be fairly easily tested in a similar way as the previous hooks REST APIIn the Model example above we didn t get to see how the REST API functions were implemented Even though it isn t necessary for the MVVM example we will still look at some trivial example code for what it can look like This code will most likely not look the same in your project it is simply here to serve an example Your real code should hopefully be better written than this typically you would need to handle things like errors retires caching and to make the code idempotent model api article tsexport interface ArticleDTO id number name string export interface CreateArticleDTO name string const API URL export const getAllArticles async Promise lt ArticleDTO null gt gt const response await fetch API URL articles if response ok throw new Error Failed to get all articles const data await response json return data export const postArticle async createData CreateArticleDTO Promise lt ArticleDTO null gt gt const response await fetch API URL articles method POST headers Content Type application json body JSON stringify createData if response ok throw new Error Failed to create article const data await response json return data Dennis PerssonFollow I m a former teacher writing articles about software development and everything around it My ambition is to provide people all around the world with free education and humorous reading FAQQ What is a View A View is a substantial part of the UI It can be the complete viewport or it can be a component within the viewport which should handle its own state and its own data I don t know in which way you have worked with container and components in React or smart and dumb components or whatever you call them But if you think of a component as a dumb component that is not a View that s just a part of a View Buttons input field and small components are all components not Views Q Why is there a ViewController in the MVVM implementation The ViewController is added as a part of the View to split the user interface implementation from its logic This allows the View to be tested more easily since the view logic and UI can be tested separately The downside is that we get more components to test render and maintain Another reason to add this extra layer is to serve as a bridge between the View and the ViewModel By doing this we can keep more of the view logic inside the View layer instead of spilling it over to the ViewModel which is shared by multiple Views There s no need for a ViewModel to know about the internal state s of the View that utilizes it Q Do I really need a ViewController for my each View component That depends on what you think of when you say View Read the question What is a View If the component you are writing isn t considered to be a View you won t need and neither shouldn t write a ViewController for it It is definitely overkill to add a ViewController for a trivial button component If the component you implement really is a View I would suggest adding its view logic to a ViewController for testing purpose and for being consistent with how you implement you Views Q How to implement MVVM in React without a ViewController If you don t want to split the View into a View and ViewController simply put all of the view logic in the ViewController into the View component itself The other option would be to put parts or all of that logic in the ViewModel but then the ViewModel would contain a lot of view logic that is specific to certain Views which would make it confusing and quite huge Q Why do we use hooks to implement the ViewController The ViewController could be implemented in multiple ways We could for example implement the View and ViewController as two components where the ViewController component would be the main component which simply passes props to the View component That solution would increase the virtual and possible even physical DOM since it would require two components instead of one Q Can we implement MVVM in React using old class components Yes of course But in this article we use functional components Class components are old and should not be used anymore Q I have seen MVVM being implemented using dependency injection in React Good for you I have seen class components using that approach which suits well there Implementing MVVM in React with functional components comes with other solutions Hooks are more familiar to React developers than dependency injection patterns For that reason this example uses React hooks to implement MVVM Q Should my React MVVM application only include a single Model Probably not You will likely have multiple models in your application Each model will also come with a ViewModel which utilizes the Model Q Should my React MVVM application only include a single ViewModel No Each Model will have a ViewModel If you have multiple Models you may also have multiple ViewModels Q Should I have one or several ViewController for each ViewModel You should have one ViewController for each View Several ViewControllers will use the same ViewModel ViewControllers like useArticleViewController useArticlesViewController and useCreateArticleViewController will all share the same ArticleViewModel Q Can I only use a single ViewModel in a ViewController No you can use many The ViewController ViewModel relation is a many to many relation not a many to one relation A View can use data from multiple models and will in that case use multiple ViewModels For example a useArticleViewController could utilize both a ArticleViewModel and a AuthorViewModel Q Why do you wrap createArticle function in onCreateArticleClick in the ViewController This is done for two reasons First reason is just for naming conventions to keep view logic such as clicks handling in the ViewController rather than in the ViewModel The second reason is because the ViewController has access to the internal state of the View That makes it possible to update onCreateArticleClick with logic from the view such as text from input fields Q I have a component which doesn t need the Model do I still need use a ViewModel in the ViewController If I would answer yes what would you write there It s totally fine and even normal to have components without ViewModels Q Do I still need testing libraries like React Test Renderer Enzyme and React Testing Library Yes and no You still have UI to test But the only place you need UI testing libraries like those are in the View files and those all consists of pure UI elements which you arguably may not need to test The hooks for the ViewController ViewModel and Model can all be tested with React Hooks Testing Library What so awesome with that Well look at the tiny documentation It s all you need honestly Q What folder structure would you recommend You can see the folder structure I used in this example by looking at the imports and filenames In general I would claim there are several folder structures that works use whatever approach you and at least some of your colleagues find logical Q What if I don t want to use TypeScript Well that s up to you Just remove the types They are only there to help Q What if I use React Native You can use the same code for React Native as well with just some minor modifications Q How does MVVM help with testing Two things decides how much tests will burden or save you One thing is the architecture of the code MVVM will by design make the code easier to test by separating concerns of each layer in the application The other thing that helps you is how you structure your tests and what libraries you use to write the tests If you aren t satisfied with the FAQ I know a guy you can ask Dennis PerssonFollow I m a former teacher writing articles about software development and everything around it My ambition is to provide people all around the world with free education and humorous reading	2023-04-16 15:29:52
海外TECH	DEV Community	CSS Text Transform: You Don't Need JavaScript to Capitalize Your Text	https://dev.to/nialljoemaher/css-text-transform-you-dont-need-javascript-to-capitalize-your-text-49io	CSS Text Transform You Don x t Need JavaScript to Capitalize Your TextSometimes we over engineer things In this previous article I showed you how to capitalize a string with JavaScript Here s a snippet from it let str hello world let capitalizedStr str slice toUpperCase str slice console log capitalizedStr Hello world This might be useful in some cases but if you are doing it to display a value there is an easier way CSS Text Transform PropertyThe CSS text transform property is used to specify text capitalization in an element This property can be applied to any text containing element like paragraphs headings lists etc The text transform property accepts the following values none Leaves the value unchanged capitalize Capitalize the valueuppercase Uppercase the valuelowercase Lowercase the valueSo to capitalize our paragraphs it would be as simple as applying the following in our CSS p text transform capitalize The CSS text transform property is a powerful tool for manipulating text styles on a web page making them convenient to know Follow me on Twitter or connect on LinkedIn Want to make friends and learn from peers You can join our free web developer community here	2023-04-16 15:19:11
金融	◇◇　保険デイリーニュース　◇◇（損保担当者必携！）	保険デイリーニュース(04/17)	http://www.yanaharu.com/ins/?p=5167	位置情報	2023-04-16 15:02:32
ニュース	BBC News - Home	Nurses' strikes could continue till Christmas, warns RCN union leader	https://www.bbc.co.uk/news/health-65291267?at_medium=RSS&at_campaign=KARANGA	weeks	2023-04-16 15:50:47
ニュース	BBC News - Home	SNP says finances are balanced after crisis reports	https://www.bbc.co.uk/news/uk-scotland-scotland-politics-65288590?at_medium=RSS&at_campaign=KARANGA	crisis	2023-04-16 15:10:10
ニュース	BBC News - Home	West Ham 2-2 Arsenal: Bukayo Saka misses penalty as Gunners let slip two-goal lead	https://www.bbc.co.uk/sport/football/65223931?at_medium=RSS&at_campaign=KARANGA	West Ham Arsenal Bukayo Saka misses penalty as Gunners let slip two goal leadBukayo Saka misses a penalty as leaders Arsenal draw at West Ham in a blow to their hopes of winning the Premier League	2023-04-16 15:25:05
ニュース	BBC News - Home	Aston Villa 0-1 Chelsea: Holders reach Women's FA Cup final with narrow win	https://www.bbc.co.uk/sport/football/65277169?at_medium=RSS&at_campaign=KARANGA	Aston Villa Chelsea Holders reach Women x s FA Cup final with narrow winHolders Chelsea book their place in the Women s FA Cup final with a narrow victory over Aston Villa and remain on course to win the trophy for the third year in a row	2023-04-16 15:18:49