What is the reason for this problem "Cannot convert an argument of type class org.json.JSONArray" to action-native android?

Question

I am trying to write a plugin to get an applicator with the package name and icon in native-native. I get all the necessary data in the form of a JSONArray and the images are stored in an SD card.

I use a callback to return the result (JSON Array) back to javascript (Success or failure). I get the above error.

Please find the java code that retrieves the data as shown below.

package com.sampleapp;

import com.facebook.react.ReactPackage; import com.facebook.react.bridge.Callback; import com.facebook.react.bridge.JavaScriptModule; 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.uimanager.ViewManager; import com.facebook.react.views.drawer.ReactDrawerLayoutManager; import com.facebook.react.views.image.ReactImageManager; import com.facebook.react.views.progressbar.ReactProgressBarViewManager; import com.facebook.react.views.scroll.ReactHorizontalScrollViewManager; import com.facebook.react.views.scroll.ReactScrollViewManager; import com.facebook.react.views.switchview.ReactSwitchManager; import com.facebook.react.views.text.ReactRawTextManager; import com.facebook.react.views.text.ReactTextViewManager; import com.facebook.react.views.text.ReactVirtualTextViewManager; import com.facebook.react.views.textinput.ReactTextInputManager; import com.facebook.react.views.toolbar.ReactToolbarManager; import com.facebook.react.views.view.ReactViewManager; import com.facebook.react.views.viewpager.ReactViewPagerManager; public class ToastModule extends ReactContextBaseJavaModule { private static final String DURATION_SHORT_KEY = "SHORT"; private static final String DURATION_LONG_KEY = "LONG"; public static JSONArray applist; public ToastModule(ReactApplicationContext reactContext) { super(reactContext); } @Override public String getName() { return "ToastAnd"; } @ReactMethod public void show(Callback errorCallback, Callback successCallback) { try { //get a list of installed apps. PackageManager pm = getReactApplicationContext().getPackageManager(); List<ApplicationInfo> packages = pm.getInstalledApplications(0); JSONArray app_list = new JSONArray(); int cnt = 0; String path = getSDPath(); makeRootDirectory(path + "/com.framework.xxx/"); makeRootDirectory(path + "/com.framework.xxx/Cache/"); for (ApplicationInfo packageInfo : packages) { try { if (getReactApplicationContext().getPackageManager().getLaunchIntentForPackage(packageInfo.packageName) != null) { JSONObject info = new JSONObject(); info.put("name", packageInfo.loadLabel(pm)); info.put("packagename", packageInfo.packageName); String img_name = "/com.ionicframework.xxx/Cache/" + packageInfo.packageName + ".png"; info.put("img", path + img_name); //cheak exist or not File cheakfile = new File(path + img_name); if (!cheakfile.exists()) { Drawable icon = pm.getApplicationIcon(packageInfo); if (icon != null) { drawableTofile(icon, path + img_name); } } app_list.put(cnt++, info); } } catch (Exception ex) { System.err.println("Exception: " + ex.getMessage()); } } applist = app_list; successCallback.invoke(applist); } catch (Exception e) { errorCallback.invoke(e.getMessage()); } } public static void drawableTofile(Drawable drawable,String path) { File file = new File(path); Bitmap bitmap=((BitmapDrawable)drawable).getBitmap(); ByteArrayOutputStream bos = new ByteArrayOutputStream(); bitmap.compress(Bitmap.CompressFormat.PNG, 100 /*ignored for PNG*/, bos); byte[] bitmapdata = bos.toByteArray(); //write the bytes in file FileOutputStream fos; try { fos = new FileOutputStream(file); fos.write(bitmapdata); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public String getSDPath() { File SDdir = null; boolean sdCardExist= Environment.getExternalStorageState().equals(android.os.Environment.MEDIA_MOUNTED); if(sdCardExist){ SDdir=Environment.getExternalStorageDirectory(); } if(SDdir!=null){ return SDdir.toString(); } else{ return null; } } public static void makeRootDirectory(String filePath) { File file = null; try { file = new File(filePath); if (!file.exists()) { file.mkdirs(); //make Directory } } catch (Exception e) { e.printStackTrace(); } } } 

In android.index.js, I call my own method, as shown below:

 /** * Sample React Native App * https://github.com/facebook/react-native */ 'use strict'; var React = require('react-native'); var { AppRegistry, StyleSheet, Text, View, } = React; var toastMessage = require('./sampleToast'); toastMessage.show( (msg) => { console.log(msg); }, (result) => { alert(JSON.stringify(result)); } ); var SampleApp = React.createClass({ render: function() { return ( <View style={styles.container}> <Text style={styles.welcome}> Welcome to React Native! </Text> <Text style={styles.instructions}> To get started, edit index.android.js </Text> <Text style={styles.instructions}> Shake or press menu button for dev menu </Text> </View> ); } }); var styles = StyleSheet.create({ container: { flex: 1, justifyContent: 'center', alignItems: 'center', backgroundColor: '#F5FCFF', }, welcome: { fontSize: 20, textAlign: 'center', margin: 10, }, instructions: { textAlign: 'center', color: '#333333', marginBottom: 5, }, }); AppRegistry.registerComponent('SampleApp', () => SampleApp); 

But in java code when returning the applicator (successCallback.invoke (applist);) I get the above error.

Could you help me where I am doing wrong. Thanks

Detailed error:

 Exception in native call from JS 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: java.lang.RuntimeException: Cannot convert argument of type class org.json.JSONArray 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at com.facebook.react.bridge.Arguments.fromJavaArgs(Arguments.java:55) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at com.facebook.react.bridge.CallbackImpl.invoke(CallbackImpl.java:27) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at com.sampleapp.ToastModule.show(ToastModule.java:100) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at java.lang.reflect.Method.invokeNative(Native Method) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at java.lang.reflect.Method.invoke(Method.java:515) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at com.facebook.react.bridge.BaseJavaModule$JavaMethod.invoke(BaseJavaModule.java:106) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at com.facebook.react.bridge.NativeModuleRegistry$ModuleDefinition.call(NativeModuleRegistry.java:143) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at com.facebook.react.bridge.NativeModuleRegistry.call(NativeModuleRegistry.java:64) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at com.facebook.react.bridge.CatalystInstance$NativeModulesReactCallback.call(CatalystInstance.java:366) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at com.facebook.react.bridge.queue.NativeRunnable.run(Native Method) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at android.os.Handler.handleCallback(Handler.java:733) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at android.os.Handler.dispatchMessage(Handler.java:95) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at com.facebook.react.bridge.queue.MessageQueueThreadHandler.dispatchMessage(MessageQueueThreadHandler.java:31) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at android.os.Looper.loop(Looper.java:136) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at com.facebook.react.bridge.queue.MessageQueueThread$1.run(MessageQueueThread.java:137) 11-14 09:01:24.780 20592-20624/com.sampleapp E/unknown:React: at java.lang.Thread.run(Thread.java:841) 

Answer 1

When working with Native bridges, calling calls must be called with WritableNative components from the com.facebook.react.bridge package.

Instead of JSONObject use WritableNativeMap .
Instead of JSONArray use WritableNativeArray .

For example, with WritableNativeMap :

 @ReactMethod public void reactMethod(Callback onSuccess) { WritableMap resultData = new WritableNativeMap(); resultData.putString("key1", "data"); resultData.putString("key2", "data2"); onSuccessCallback(resultData); } 

In your case, you should have something like:

 public static WritableArray applist; // ... @ReactMethod public void show(Callback errorCallback, Callback successCallback) { try { //get a list of installed apps. PackageManager pm = getReactApplicationContext().getPackageManager(); List<ApplicationInfo> packages = pm.getInstalledApplications(0); WritableArray app_list = new WritableNativeArray(); // ... for (ApplicationInfo packageInfo : packages) { try { if (getReactApplicationContext().getPackageManager().getLaunchIntentForPackage(packageInfo.packageName) != null) { WritableMap info = new WritableNativeMap(); info.putString("name", packageInfo.loadLabel(pm).toString()); info.putString("packagename", packageInfo.packageName); // ... app_list.pushMap(info); } } catch (Exception ex) { System.err.println("Exception: " + ex.getMessage()); } } applist = app_list; successCallback.invoke(applist); } catch (Exception e) { errorCallback.invoke(e.getMessage()); } }