kotlin-使用kotlin开发的二维码生成器.zip

# QRCode-Kotlin Creating QRCodes in Kotlin (and Java) is harder than it should be. **QRCode-Kotlin aims to bring a simple, straightforward and customizable way to create QRCodes**, especially in the backend. It is with this mission in mind that we keep doing our best to learn how developers use this library and their goals so that we can provide a better library/API for them. Please, feel free to share if and how you're using this project ^^ * **Pure Kotlin:** Rewritten on pure Kotlin from a reference implementation of the QRCode spec by [Kazuhiko Arase](https://github.com/kazuhikoarase/qrcode-generator) * **Lightweight:** No dependencies, `~115KB` and it does what it says on the tin. * **Easy to use:** Quickly and easily implement QRCodes with few lines of code. * **Good-looking:** Many developers don't have time and sometimes knowledge to implement the perfect QRCode, so this library tries to generate good-looking QRCodes by default. * **Server friendly:** The JVM version is mainly focused on a personal use-case where I needed to generate QRCodes on the backend, but all libraries I found were either complex or huge, usually both. * **Multiplatform:** This is a KMP library with support to Java, JavaScript, Android, iOS and tvOS. ## 1. Installation The library is available from [Maven Central](https://search.maven.org/artifact/io.github.g0dkar/qrcode-kotlin/4.1.0/qrcode-kotlin) and [NPM JS](https://www.npmjs.com/package/qrcode-kotlin), so you can add it to your project as a dependency like any other: **Gradle:** ```groovy // Use this for both Android and JVM implementation("io.github.g0dkar:qrcode-kotlin:4.1.1") ``` **Maven - JVM:** ```xml <dependency> <groupId>io.github.g0dkar</groupId> <artifactId>qrcode-kotlin-jvm</artifactId> <version>4.1.1</version> </dependency> ``` **Maven - Android:** ```xml <dependency> <groupId>io.github.g0dkar</groupId> <artifactId>qrcode-kotlin-android</artifactId> <version>4.1.1</version> </dependency> ``` **NodeJS:** ```shell npm install [email protected] ``` **Browser:** ```html <script src="https://cdn.jsdelivr.net/gh/g0dkar/qrcode-kotlin@main/release/qrcode-kotlin.min.js" type="application/javascript"></script> ``` ## Usage To create QRCodes, the main class that should be used is the `qrcode.render.QRCode` class. It has static methods to help you create a QRCode the way you want: ```kotlin // Use one of these: val squares = QRCode.ofSquares() val circles = QRCode.ofCircles() val roundedSquares = QRCode.ofRoundedSquares() ``` With that, you'll have a [QRCodeBuilder](src/commonMain/kotlin/qrcode/QRCodeBuilder.kt) instance. It has methods to adjust colors, size, spacing, add a logo and more! Also, make sure to check the [Colors](src/commonMain/kotlin/qrcode/color/Colors.kt) class as well. Here's a code to get you started: ```kotlin val helloWorld = QRCode.ofSquares() .withColor(Colors.DEEP_SKY_BLUE) // Default is Colors.BLACK .withSize(10) // Default is 25 .build("Hello world!") // By default, QRCodes are rendered as PNGs. val pngBytes = helloWorld.render() FileOutputStream("hello-world.png").use { it.write(pngBytes) } ``` We highly recommend that you check out some examples: * [All sorts of shapes](examples/kotlin/src/main/kotlin/Example01-Shapes.kt): Squares, Circles, Rounded Squares and Custom shapes * [All about colors](examples/kotlin/src/main/kotlin/Example02-Colors.kt): Foreground, Background, Transparent backgrounds, Linear Gradient colors * [Adding a Logo](examples/kotlin/src/main/kotlin/Example03-Logo.kt): Add a logo and remove the cells behind it, or don't :) * [SVG QRCodes](examples/kotlin/src/main/kotlin/Example04-SVG.kt): How to extend the renderer to render SVG (uses [JFree SVG](https://github.com/jfree/jfreesvg)) * [The banner on the top of this README](examples/kotlin/src/main/kotlin/ProjectLogo.kt): Yup, all done with the library ^^ The examples show pretty much all that can be done with the library! Even how to extend it so that it can create SVG QRCodes ;) You can mix and match all those together. Try generating the library logo and banner with gradients and all in SVG ;) ### Spring Framework and/or Spring Boot As said earlier, one of the main reasons I developed this library was to use it on a backend application. So it is only natural to show how to do that :) This Spring Framework/Boot controller method can generate QRCodes of a given content: ```kotlin import org.springframework.core.io.ByteArrayResource import org.springframework.http.HttpHeaders.CONTENT_DISPOSITION import org.springframework.http.MediaType.IMAGE_PNG_VALUE @GetMapping("/qrcode") fun generateQrCode(content: String): ResponseEntity<ByteArrayResource> { val pngData = QRCode().ofSquares() .build(content) .render() val resource = ByteArrayResource(pngData, IMAGE_PNG_VALUE) return ResponseEntity.ok() .header(CONTENT_DISPOSITION, "attachment; filename=\"qrcode.png\"") .body(resource) } ```