Question

我正在尝试启动我的React Native Redis模块并运行，但出现以下错误。当我尝试引用任何功能

TypeError: undefined is not an object (evaluating '_reactNativeRedispubsub.RedisClient.redisConnect')

RedisClient.js

/**
 * This exposes our Android code into our RN project
 */

import { NativeModules } from "react-native";
module.exports = NativeModules.RedisClient;

通过Redison Jar进行实际Redis调用的文件 RedisClient.java

package com.redispubsub;

import android.util.Log;
import android.widget.Toast;

import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.bridge.ReactContextBaseJavaModule;
import com.facebook.react.bridge.ReactMethod;
import com.facebook.react.modules.core.DeviceEventManagerModule;

import java.text.DateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.Locale;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.redisson.Redisson;
import org.redisson.api.RTopic;
import org.redisson.api.RedissonClient;
import org.redisson.api.listener.MessageListener;
import org.redisson.client.RedisConnectionException;
import org.redisson.client.codec.StringCodec;
import org.redisson.config.Config;


public class RedisClient extends ReactContextBaseJavaModule {
  private final ReactApplicationContext reactContext;
  private RedissonClient mredissonClient;

  public RedisClient(ReactApplicationContext reactContext) {
    super(reactContext);
    this.reactContext = reactContext;
  }
  @Override
  public String getName() {
    return "RedisClient";
  }

  @ReactMethod
  public void redisConnect(String ipPort) {
    //Redisson client setup to be done in background thread
    try {
      
      Config config = new Config();
      config.useSingleServer().setAddress(ipPort); //IPAddress of Redis and port
      mredissonClient = Redisson.create(config);
    } catch (Exception ex) {
      ex.printStackTrace();
    }
  }

  @ReactMethod
  public void subscribe(String channelName) {

    if (mredissonClient != null) {
      RTopic subscribeTopic = mredissonClient.getTopic(channelName, StringCodec.INSTANCE); //Channel to listen and Codec.
      subscribeTopic.addListener(new MessageListener < String > () {
        @Override
        public void onMessage(String channel, String msg) {
          reactContext
            .getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
            .emit(channel, msg);
        }
      });
    } else {

    }

  }

  @ReactMethod
  public long publish(String ChannelName, String msg) {
    long clientsReceivedMessage = 0;
    if (mredissonClient != null) {
      //Redisson publish
      RTopic topic = mredissonClient.getTopic(ChannelName, StringCodec.INSTANCE);
      try {

        clientsReceivedMessage = topic.publish(msg); //Publishing lat lon to Coros
      } catch (Exception ex) {
        ex.printStackTrace();
      }
    } else {

    }
    return clientsReceivedMessage;

  }


}

将方法公开给Java脚本 RedisCleintPackage.java

package com.redispubsub;

import com.facebook.react.ReactPackage;
import com.facebook.react.bridge.NativeModule;
import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.uimanager.ViewManager;
import com.facebook.react.bridge.JavaScriptModule;

import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.text.DateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashMap;
import java.util.Locale;

public class RedisClientPackage implements ReactPackage {
  @Override
  public List < NativeModule > createNativeModules(ReactApplicationContext reactContext) {
    List < NativeModule > modules = new ArrayList < > ();

    modules.add(new RedisClient(reactContext));

    return modules;
  }

  public List < Class << ? extends JavaScriptModule >> createJSModules() {
    return Arrays.asList();
  }

  @Override
  public List < ViewManager > createViewManagers(ReactApplicationContext reactContext) {
    return Collections.emptyList();

  }
}

此_reactNativeRedispubsub.RedisClient.redisConnect是否表示其未正确调用对象？

我很困惑为什么它不使用RedisClient.java中存在的redisConnect

这整个代码在我运行MainActivity的我的react-native android项目中正常工作，但是当我将其发布到npm并进行npm安装时，它的工作正常

Answer 1

我明白了

以下更改需要在 redisclient.js

/ ** *这会将我们的Android代码公开到我们的RN项目中 * /

import { NativeModules } from "react-native";

const { RedisClient } = NativeModules;

export {
  RedisClient
}

Answer 2

我使用这样的东西：

import {NativeModules} from 'react-native';
module.exports = NativeModules.RedisClient;

React Native不从父应用程序调用Android本机方法

2 个答案: