`new NativeEventEmitter()` was called with a non-null argument without the required `addListener` method.

[Arnab2021]

Hi

I am using this package to get the WIFI state. When I am running the App I am getting this error - new NativeEventEmitter() was called with a non-null argument without the required addListener method. new NativeEventEmitter() was called with a non-null argument without the required addListener method.

I have all the installation process and the coing standard as per the document.

Please help me to get rid of that.

[geroale]

Same issue here

[willyhorizont]

I have this message before but I don't see it again after I change my code to

` // utils.js import { locationAction } from '../slices/locationSlice';

export const listenLocationChange = async (SystemSetting, dispatch) => { return await SystemSetting.addLocationListener((enable) => { dispatch(locationAction.setIsLocationEnabled(enable)); }); };

// Components.js useEffect(() => { const locationListener = listenLocationChange(SystemSetting, dispatch); return () => { if (typeof locationListener?.remove === 'function') SystemSetting.removeListener(locationListener); }; }, []); `

I hope you already solve your problem

[GabLeRoux]

I worked on this recently and had similar issue. Here's the same comment as above with proper indentation and syntax highlighting.

// utils.js
import { locationAction } from '../slices/locationSlice';

export const listenLocationChange = async (SystemSetting, dispatch) => {
  return await SystemSetting.addLocationListener((enable) => {
    dispatch(locationAction.setIsLocationEnabled(enable));
  });
};

// Components.js
useEffect(() => {
  const locationListener = listenLocationChange(SystemSetting, dispatch);
  return () => {
    if (typeof locationListener?.remove === 'function')
      SystemSetting.removeListener(locationListener);
  };
}, []);

In other word, the fix is to actually add and remove the listeners using SystemSetting.addLocationListener and SystemSetting.removeListener.

Depending on the implementation, these changes could actually be directly in the same component.

---

Edit 2023-09-19: The library's code could actually be updated according to the following stack overflow post: https://stackoverflow.com/questions/69538962/new-nativeeventemitter-was-called-with-a-non-null-argument-without-the-requir

I added the functions to SystemSetting.java and exposed them in SystemSetting.d.ts and it looks like it worked so this could probably be a better solution.

diff --git a/SystemSetting.d.ts b/SystemSetting.d.ts
index 403808c..ab96e4d 100644
--- a/SystemSetting.d.ts
+++ b/SystemSetting.d.ts
@@ -31,6 +31,8 @@ interface VolumeData {
 }
 
 interface SystemSetting {
+  addListener: (eventName: string) => void;
+  removeListeners: (count: number) => void;
   getBrightness: () => Promise<number>;
   setBrightness: (val: number) => Promise<boolean>;
   setBrightnessForce: (val: number) => Promise<boolean>;
diff --git a/android/src/main/java/com/ninty/system/setting/SystemSetting.java b/android/src/main/java/com/ninty/system/setting/SystemSetting.java
index 8ade5e6..c5d3adc 100644
--- a/android/src/main/java/com/ninty/system/setting/SystemSetting.java
+++ b/android/src/main/java/com/ninty/system/setting/SystemSetting.java
@@ -199,6 +199,25 @@ public class SystemSetting extends ReactContextBaseJavaModule implements Activit
         return SystemSetting.class.getSimpleName();
     }
 
+    /**
+     *
+     * @see https://stackoverflow.com/questions/69538962/new-nativeeventemitter-was-called-with-a-non-null-argument-without-the-requir
+     * @param eventName the name of the event
+     */
+    @ReactMethod
+    public void addListener(String eventName) {
+
+    }
+
+    /**
+     * @see https://stackoverflow.com/questions/69538962/new-nativeeventemitter-was-called-with-a-non-null-argument-without-the-requir
+     * @param count the number of listeners to remove
+     */
+    @ReactMethod
+    public void removeListeners(Integer count) {
+
+    }
+
     @ReactMethod
     public void setScreenMode(int mode, Promise promise) {
         mode = mode == Settings.System.SCREEN_BRIGHTNESS_MODE_MANUAL ? mode : Settings.System.SCREEN_BRIGHTNESS_MODE_AUTOMATIC;