我想使用方法sendEvent(),但是如何获取ReactContext reactContext？
private void sendEvent(ReactContext reactContext,String eventName,@Nullable WritableMap params) {reactContext
.getJSModule(DeviceEventManagerModule.RCTDeviceEventEmitter.class)
.emit(eventName,params);}
解决方法
我通过在MainActivity类上保存对ReactInstanceManager的静态引用,并添加了一个public static getContext()方法来暂时解决了这个问题.它感觉不对,但似乎有效.
public final class MainActivity extends ReactActivity {
private static ReactInstanceManager sReactInstanceManager = null;
/* [...] */
@Override
protected ReactInstanceManager createReactInstanceManager() {
ReactInstanceManager manager = super.createReactInstanceManager();
sReactInstanceManager = manager;
return manager;
}
public static ReactContext getContext() {
if (sReactInstanceManager == null){
// This doesn't seem to happen ...
throw new IllegalStateException("Instance manager not available");
}
final ReactContext context = sReactInstanceManager.getCurrentReactContext();
if (context == null){
// This really shouldn't happen ...
throw new IllegalStateException("React context not available");
}
return context;
}
/* [...] */
}
createReactInstanceManager()由ReactActivity的onCreate()方法调用,所以我认为可以安全地假设sReactInstanceManager将指向正确的实例,但不要相信我的话.
