react native native module

React Native Native Modules，官方地址：https://facebook.github.io/react-native/docs/native-modules-android.html

第一步：使用Android Studio在项目中增加两个Class

TestReactModule.java

package com.tqstablet;

import android.widget.Toast;
import android.app.Activity;
import android.content.Intent;
import android.net.Uri;
import android.Manifest;
import android.app.Activity;
import android.app.AlertDialog;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.Context;
import android.content.pm.PackageManager;
import android.location.LocationManager;
import android.os.Build;
import android.provider.Settings;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.TextView;

import com.facebook.react.bridge.NativeModule;
import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.bridge.ReactContext;
import com.facebook.react.bridge.ReactContextBaseJavaModule;
import com.facebook.react.bridge.ReactMethod;
import com.facebook.react.bridge.Promise;
import com.facebook.react.bridge.BaseActivityEventListener;
import com.facebook.react.bridge.ActivityEventListener;

import java.util.Map;
import java.util.HashMap;

import android.os.Build;
import com.facebook.react.bridge.Callback;

/**
 * Created by ChenWes on 2018-05-24.
 */

public class TestReactModule extends ReactContextBaseJavaModule {

    // Toast code
    private static final String DURATION_SHORT_KEY = "SHORT";
    private static final String DURATION_LONG_KEY = "LONG";

    // image code
    private static final int IMAGE_PICKER_REQUEST = 467081;
    private static final String E_ACTIVITY_DOES_NOT_EXIST = "E_ACTIVITY_DOES_NOT_EXIST";
    private static final String E_PICKER_CANCELLED = "E_PICKER_CANCELLED";
    private static final String E_FAILED_TO_SHOW_PICKER = "E_FAILED_TO_SHOW_PICKER";
    private static final String E_NO_IMAGE_DATA_FOUND = "E_NO_IMAGE_DATA_FOUND";

    private Promise mPromise;

    private final ActivityEventListener mActivityEventListener = new BaseActivityEventListener() {
        @Override
        public void onActivityResult(Activity activity, int requestCode, int resultCode, Intent intent) {
            // Toast.makeText(getReactApplicationContext(), "找到照片" + requestCode + "****" + resultCode, Toast.LENGTH_SHORT).show();
            if (requestCode == IMAGE_PICKER_REQUEST) {
                if (mPromise != null) {
                    if (resultCode == Activity.RESULT_CANCELED) {
                        // Toast.makeText(getReactApplicationContext(), "RESULT_CANCELED", Toast.LENGTH_SHORT).show();
                        mPromise.reject(E_PICKER_CANCELLED, "Image picker was cancelled");
                    } else if (resultCode == Activity.RESULT_OK) {
                        // Toast.makeText(getReactApplicationContext(), "RESULT_OK", Toast.LENGTH_SHORT).show();
                        Uri uri = intent.getData();

                        Toast.makeText(getReactApplicationContext(), uri.toString(), Toast.LENGTH_SHORT).show();
                        if (uri == null) {
                            mPromise.reject(E_NO_IMAGE_DATA_FOUND, "No image data found");
                        } else {
                            mPromise.resolve(uri.toString());
                        }
                    }
                    mPromise = null;
                }
            }
        }
    };

    public TestReactModule(ReactApplicationContext reactContext) {
        super(reactContext);

        // Add the listener for `onActivityResult`
        reactContext.addActivityEventListener(mActivityEventListener);
    }

    @Override
    public String getName() {
        return "TestReactModule";
    }

    @Override
    public Map<String, Object> getConstants() {
        final Map<String, Object> constants = new HashMap<>();
        constants.put(DURATION_SHORT_KEY, Toast.LENGTH_SHORT);
        constants.put(DURATION_LONG_KEY, Toast.LENGTH_LONG);
        return constants;
    }

    /* 无回调的方式 *************************************************************/

    @ReactMethod
    public void show(String message, int duration) {
        Toast.makeText(getReactApplicationContext(), "Android :" + message, duration).show();
    }
    /* 事件回调的方式 *************************************************************/

    @ReactMethod
    public void getSystemModel(Callback result) {
        String sysModel = Build.MODEL;
        result.invoke(sysModel);
    }

    @ReactMethod
    public void getSystemModelAndVersion(Callback result) {
        String sysModel = Build.MODEL;
        String sysVersion = Build.VERSION.RELEASE;
        result.invoke(sysModel, sysVersion);
    }

    /* Promise的方式 *************************************************************/

    @ReactMethod
    public void pickImage(final Promise promise) {
        Activity currentActivity = getCurrentActivity();

        if (currentActivity == null) {
            promise.reject(E_ACTIVITY_DOES_NOT_EXIST, "Activity doesn't exist");
            return;
        }
        // Store the promise to resolve/reject when picker returns data
        mPromise=null;
        mPromise = promise;

        try {
            final Intent galleryIntent = new Intent(Intent.ACTION_PICK);
            galleryIntent.setType("image/*");
            final Intent chooserIntent = Intent.createChooser(galleryIntent, "Pick an image");
            currentActivity.startActivityForResult(chooserIntent, IMAGE_PICKER_REQUEST);

            Toast.makeText(getReactApplicationContext(), "弹出照片库", Toast.LENGTH_SHORT).show();
        } catch (Exception e) {
            mPromise.reject(E_FAILED_TO_SHOW_PICKER, e);
            mPromise = null;
        }
    }
}

TestReactModulePackage.java

package com.tqstablet;

import com.facebook.react.ReactPackage;
import com.facebook.react.bridge.NativeModule;
import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.uimanager.ViewManager;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

/**
 * Created by ChenWes on 2018-05-24.
 */

public class TestReactModulePackage implements ReactPackage {
    @Override
    public List<ViewManager> createViewManagers(ReactApplicationContext reactContext) {
        return Collections.emptyList();
    }

    @Override
    public List<NativeModule> createNativeModules(ReactApplicationContext reactContext) {
        List<NativeModule> modules = new ArrayList<>();

        modules.add(new TestReactModule(reactContext));

        return modules;
    }
}

第二步：在MainApplication.java中增加引用

package com.tqstablet;

import android.app.Application;

import com.facebook.react.ReactApplication;
import com.AlexanderZaytsev.RNI18n.RNI18nPackage;
import com.imagepicker.ImagePickerPackage;
import com.learnium.RNDeviceInfo.RNDeviceInfo;
import com.facebook.react.ReactNativeHost;
import com.facebook.react.ReactPackage;
import com.facebook.react.shell.MainReactPackage;
import com.facebook.soloader.SoLoader;


import java.util.Arrays;
import java.util.List;

public class MainApplication extends Application implements ReactApplication {

  private final ReactNativeHost mReactNativeHost = new ReactNativeHost(this) {
    @Override
    public boolean getUseDeveloperSupport() {
      return BuildConfig.DEBUG;
    }

    @Override
    protected List<ReactPackage> getPackages() {
      return Arrays.<ReactPackage>asList(
          new MainReactPackage(),
            new RNI18nPackage(),
            new ERulerPackage(),
            new TestReactModulePackage(),
            new RNDeviceInfo(),
            new ImagePickerPackage()
      );
    }

    @Override
    protected String getJSMainModuleName() {
      return "index";
    }
  };

  @Override
  public ReactNativeHost getReactNativeHost() {
    return mReactNativeHost;
  }

  @Override
  public void onCreate() {
    super.onCreate();
    SoLoader.init(this, /* native exopackage */ false);
  }
}

第三步：在React Native中进行调用

TestModule.js

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

调用代码

import TestReactModule from '../util/TestReactModule';

<Button style={styles.menuButton} onPress={() => {
//无回调
// TestReactModule.show("平板端打开一个对话框", TestReactModule.LONG);

//回调事件
// TestReactModule.getSystemModel((getModel) => {
// Alert.alert(getModel);
// });

//回调事件，多参数
// TestReactModule.getSystemModelAndVersion((sysModel, sysVersion) => {
// Alert.alert(sysModel, sysVersion);
// });

//Promise
TestReactModule.pickImage()
.then((data) => {
Alert.alert(data);
}).catch((err) => {
Alert.alert('Err', err.message);
})

}}>
React Native 测试
</Button>