在使用ReactInstanceManager.Builder構建一個ReactInstanceManager例項的時候只能傳入一個bundle，setBundleAssetName和setJSBundleFile分別對應從assets和從一個檔案路徑載入Bundle。有時需要將業務程式碼和通用程式碼分離，也就是分成兩個bundle，這時候載入第二個Bundle就要藉助反射了。

ReactContext mReactContext = manager.getCurrentReactContext();
        final Runnable loadRN = new Runnable() {
            @Override
            public void run() {
                mReactRootView.startReactApplication(manager, "HomeScene", getLaunchOptions());
                if (BuildConfig.DEBUG_PANEL_ENTRANCE) {
                    setContentView(wrapReactRootViewWithDebugButton(mReactRootView));
                } else {
                    setContentView(mReactRootView);
                }
            }
        };
        if (mReactContext == null) {
            manager.addReactInstanceEventListener(new ReactInstanceManager.ReactInstanceEventListener() {
                @Override
                public void onReactContextInitialized(ReactContext context) {
                    ReactUtils.loadBusinessScript(context);
                    loadRN.run();
                }
            });
            manager.createReactContextInBackground();
        } else {
            ReactUtils.loadBusinessScript(mReactContext);
            loadRN.run();
        }
 

因為載入第二個的過程是放在回撥接口裡非同步執行的，所以要把startReactApplication和setContentView放在載入後面，否則沒載入完就執行會報錯。載入過程：

 public static void loadBusinessScript(ReactContext context) {
        CatalystInstance instance = context.getCatalystInstance();
//        try {
//            Method method = CatalystInstanceImpl.class
//                    .getDeclaredMethod("loadScriptFromAssets",
//                            AssetManager.class,
//                            String.class,
//                            boolean.class);
//            method.setAccessible(true);
//            method.invoke(instance, EffectApplication.getInstance().getAssets(), "assets://business.android.jsbundle", false);
//        } catch (Exception e) {
//            e.printStackTrace();
//        }
        String path = EffectApplication.getInstance().getExternalCacheDir()+"/business.android.jsbundle";
        try {
            Method method = CatalystInstanceImpl.class
                    .getDeclaredMethod("loadScriptFromFile",
                            String.class,
                            String.class,
                            boolean.class);
            method.setAccessible(true);
            method.invoke(instance, path , path , false);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
 

註釋的是從assets載入，沒註釋的是從自定義的路徑載入，這裡我把Bundle放在了app的cache資料夾下。