React Native集成到现有Android Studio项目

开发环境准备

首先按照开发环境搭建教程来安装React Native在安卓平台上所需的一切依赖软件（比如npm）。

1. 打开现在Android项目

注意：react native支持最新sdk version 必须是16以上

2. 安装JavaScript依赖包

1. $ npm install

注意：安装的过程中可能会提示react版本不正确。（react-native对react的版本有严格要求，高于或低于某个范围都不可以。本文无法在这里列出所有react native和对应的react版本要求，只能提醒读者先尝试执行npm install，然后注意观察安装过程中的报错信息，例如require [e-mail]版本, but none was installed，然后根据这样的提示，执行npm i -S [e-mail]版本。如果你使用多个第三方依赖，可能这些第三方各自要求的react版本有所冲突，此时应优先满足react-native所需要的react版本。）

react版本不对解决方法：

执行命令：

yarn add [e-mail]

2. npm install --save react react-native

注意：安装的过程中可能会forbidden 403

forbidden 403解决方法：

1.可能没设置npm镜像

yarn config set registry https://registry.npm.taobao.org --global
yarn config set disturl https://npm.taobao.org/dist --global

2.npm不是最新

查看当前版本 npm -v

查看最新版本号 npm info npm

安装最新 npm install [e-mail] - g (@ 符号后面添加你查到的最新版本号)

3.  执行命令成功

把React Native添加到你的应用中

配置maven

在你的app中 build.gradle 文件中添加 React Native 依赖:

apply plugin: 'com.android.application'

android {
    compileSdkVersion 25
    buildToolsVersion "25.0.2"
    defaultConfig {
        applicationId "bluemoon.com.cn.reactnativeapp"
        minSdkVersion 16
        targetSdkVersion 25
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
        ndk {
            abiFilters "armeabi-v7a", "x86"
        }
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
    configurations.all {
        resolutionStrategy.force 'com.google.code.findbugs:jsr305:1.3.9'
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
        exclude group: 'com.android.support', module: 'support-annotations'
    })
    compile 'com.android.support:appcompat-v7:25.3.1'
    compile 'com.android.support.constraint:constraint-layout:1.0.2'
    testCompile 'junit:junit:4.12'
    compile "com.facebook.react:react-native:+" // From node_modules.
}

在项目的build.gradle添加maven依赖入口

buildscript {
    repositories {
        jcenter()
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:2.1.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        mavenLocal()
        jcenter()
        maven {
            // All of React Native (JS, Android binaries) is installed from npm
            url "$rootDir/node_modules/react-native/android"
        }
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

修改package.json

{
  "name": "reactnativeapp",
  "version": "1.0.0",
  "private": true,
  "scripts": {
    "start": "node node_modules/react-native/local-cli/cli.js start"
  },
  "dependencies": {
    "react": "16.0.0-alpha.12",
    "react-native": "^0.46.4"
  }
}

编写MyReactActivity类

package bluemoon.com.cn.reactnativeapp;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.KeyEvent;

import com.facebook.react.ReactInstanceManager;
import com.facebook.react.ReactPackage;
import com.facebook.react.ReactRootView;
import com.facebook.react.bridge.JavaScriptModule;
import com.facebook.react.bridge.NativeModule;
import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.common.LifecycleState;
import com.facebook.react.modules.core.DefaultHardwareBackBtnHandler;
import com.facebook.react.shell.MainReactPackage;
import com.facebook.react.uimanager.ViewManager;

import java.util.List;


public class MyReactActivity extends Activity implements DefaultHardwareBackBtnHandler {
    private ReactRootView mReactRootView;
    private ReactInstanceManager mReactInstanceManager;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mReactRootView = new ReactRootView(this);
        mReactInstanceManager = ReactInstanceManager.builder()
                .setApplication(getApplication())
                .setBundleAssetName("index.android.bundle")
                .setJSMainModuleName("index.android")
                .addPackage(new MainReactPackage())
                .setUseDeveloperSupport(BuildConfig.DEBUG)
                .setInitialLifecycleState(LifecycleState.RESUMED)
                .build();
        // 注意这里的HelloWorld必须对应“index.android.js”中的
        // “AppRegistry.registerComponent()”的第一个参数
        mReactRootView.startReactApplication(mReactInstanceManager, "reactnativeapp", null);
        setContentView(mReactRootView);
    }

    @Override
    public void invokeDefaultOnBackPressed() {
        super.onBackPressed();
    }

    @Override
    protected void onPause() {
        super.onPause();

        if (mReactInstanceManager != null) {
            mReactInstanceManager.onHostPause(this);
        }
    }

    @Override
    protected void onResume() {
        super.onResume();

        if (mReactInstanceManager != null) {
            mReactInstanceManager.onHostResume(this, this);
        }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();

        if (mReactInstanceManager != null) {
            mReactInstanceManager.onHostDestroy();
        }
    }
    @Override
    public void onBackPressed() {
        if (mReactInstanceManager != null) {
            mReactInstanceManager.onBackPressed();
        } else {
            super.onBackPressed();
        }
    }
    @Override
    public boolean onKeyUp(int keyCode, KeyEvent event) {
        if (keyCode == KeyEvent.KEYCODE_MENU && mReactInstanceManager != null) {
            mReactInstanceManager.showDevOptionsDialog();
            return true;
        }
        return super.onKeyUp(keyCode, event);
    }
}

权限和声明

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="bluemoon.com.cn.reactnativeapp" >
    <uses-permission android:name="android.permission.INTERNET" />
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme" >
        <activity android:name=".MainActivity" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name="com.facebook.react.devsupport.DevSettingsActivity" /><!--开发者菜单-->
        <activity
            android:name=".MyReactActivity"
            android:label="@string/app_name"
            android:theme="@style/Theme.AppCompat.Light.NoActionBar" />
    </application>

</manifest>

在根目录新建index.android.js，并添加react native组件

'use strict';

import React from 'react';
import {
  AppRegistry,
  StyleSheet,
  Text,
  View
} from 'react-native';

class HelloWorld extends React.Component {
  render() {
    return (
      <View style={styles.container}>
        <Text style={styles.hello}>Hello, World</Text>
      </View>
    )
  }
}
var styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
  },
  hello: {
    fontSize: 20,
    textAlign: 'center',
    margin: 10,
  },
});

AppRegistry.registerComponent('reactnativeapp', () => HelloWorld);

修改MainActivity

如果你的应用会运行在Android 6.0（API level 23）或更高版本，请确保你在开发版本中有打开悬浮窗(overlay)权限

package bluemoon.com.cn.reactnativeapp;

import android.content.Intent;
import android.net.Uri;
import android.os.Build;
import android.provider.Settings;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.txt_to_hello_world).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                    if (!Settings.canDrawOverlays(MainActivity.this)) {
                        Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION,
                                Uri.parse("package:" + getPackageName()));
                        startActivityForResult(intent, 1);
                        return;
                    }
                }
                Intent i = new Intent(MainActivity.this, MyReactActivity.class);
                startActivity(i);
            }
        });
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == 1) {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
                if (!Settings.canDrawOverlays(this)) {
                    // SYSTEM_ALERT_WINDOW permission not granted...
                    Toast.makeText(this, "error", Toast.LENGTH_SHORT).show();
                    return;
                }
            }
        }
        Intent i = new Intent(MainActivity.this, MyReactActivity.class);
        startActivity(i);
    }
}

到这里就可以运行项目了！！！

还是有一点注意的是添加ndk，不然运行项目时会报错：
java.lang.UnsatisfiedLinkError: dlopen failed: "/data/data/bluemoon.com.cn.reactnativeapp/lib-main/libgnustl_shared.so" is 32-bit instead of 64-bit
app中 build.gradle 文件中添加

ndk {
    abiFilters "armeabi-v7a", "x86"
}

gradle.properties文件添加：

android.useDeprecatedNdk=true

最终集成运行结果如下：

打包APK

设置gradle变量生产签名**

$ keytool -genkey -v -keystore my-release-key.keystore -alias my-key-alias -keyalg RSA -keysize 2048 -validity 10000

设置gradle变量

signingConfigs {
    release {
        storeFile file('./my-release-key.keystore')
        storePassword "123456"
        keyAlias "my-key-alias"
        keyPassword "123456"
    }
}

buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        signingConfig signingConfigs.release
    }
}

生成离线的jsbundle文件

$ react-native bundle --platform android --dev false --entry-file index.android.js --bundle-output android/com/your-company-name/app-package-name/src/main/assets/index.android.bundle --assets-dest android/com/your-company-name/app-package-name/src/main/res/

生成发行APK包

gradle assembleRelease