7、React Native核心组件开发指南

React Native核心组件开发指南

1. 组件属性与 View 组件基础

在开发应用时,我们通常会使用 isRequired 让大部分属性成为必需项,因为我们会传递每个属性。若想让组件更具复用性,可将属性设为可选,但在实际复用前很难确定哪些属性应设为可选。

View 组件是最常用且功能多样的组件,主要用于两个方面:
- 布局 :作为其他组件的容器,可垂直或水平排列组件。
- 样式 :用于渲染简单形状(如圆形、矩形)、边框、线条或背景颜色。

以下是使用 View 创建 Avatar 圆形背景的代码:

// image-feed/1/components/Avatar.js
// ...
export default function Avatar({ size, backgroundColor, initials }) {
    const style = {
        width: size,
        height: size,
        borderRadius: size / 2,
        backgroundColor,
    }
    return (
        <View style={style} />
    )
}

这里通过

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