ReactNative-Android插件
一、编写插件
- android项目包目录下创建ToastModule.java并继承ReactContextBaseJavaModule
- 实现构造函数接收NAContext
- 重写getName方法返回模块名称
- 重写getConstants方法导出js使用常量
- 定义模块功能方法并使用@ReactMethod注解当前方法
package com.awesomeproject;
import android.widget.Toast;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import com.facebook.react.bridge.ReactApplicationContext;
import com.facebook.react.bridge.ReactContextBaseJavaModule;
import com.facebook.react.bridge.ReactMethod;
import java.util.HashMap;
import java.util.Map;
//1
public class ToastModule extends ReactContextBaseJavaModule {
private static ReactApplicationContext reactContext;
private static final String DURATION_SHORT_KEY = "SHORT";
private static final String DURATION_LONG_KEY = "LONG";
//2
public ToastModule(@NonNull ReactApplicationContext context) {
super(context);
reactContext = context;
}
//3
@NonNull
@Override
public String getName() {
return "ToastExample";
}
//4
@Nullable
@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;
}
//5
@ReactMethod
public void show(String message, int duration) {
Toast.makeText(getReactApplicationContext(), message, duration).show();
}
}
二、注册插件
- android项目包目录下创建CustomToastPackage.java并继承ReactPackage
- 重写createNativeModules方法添加模块,以便js调用
- 在MainApplication.java的getPackages方法中添加新插件注册
package com.awesomeproject;
import androidx.annotation.NonNull;
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;
public class CustomToastPackage implements ReactPackage {
@NonNull
回调使用
代码语言:javascript复制import com.facebook.react.bridge.Callback;
Callback.invoke(a b);
Promises
使用await调用配置了promise的方法并配以async
代码语言:javascript复制import com.facebook.react.bridge.Promise;
promise.resolve(map);
promise.reject(E_LAYOUT_ERROR, e);
js调用测试
代码语言:javascript复制export default class HelloWorldApp extends Component {
handleClick(e) {
ToastExample.show('hello app', ToastExample.SHORT);
}
render() {
return (
<View style={{ flex: 1, justifyContent: "center", alignItems: "center" }}>
<Button
onPress={this.handleClick}
title="Test Toast"
color="#841584"
accessibilityLabel="Learn more about this purple button"
/>
</View>
);
}
}