Co jest przyczyną tego problemu "Nie można przekonwertować argumentu typu klasy org.json.JSONArray" w natywnym systemie Android reagowania?

Question

Próbuję napisać wtyczkę, aby pobrać listę aplikacji z nazwą pakietu i ikoną w reaktywnym natywnym języku. Otrzymuję wszystkie wymagane dane w postaci JSONArray, a obrazy są zapisywane na sdcard.

Używam wywołania zwrotnego, aby przywrócić wynik (tablica JSON) do javascript (powodzenie lub niepowodzenie). Otrzymuję powyższy błąd.

Proszę znaleźć kod Java, który pobiera szczegóły, jak poniżej.

pakiet 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(); 
     } 
    } 
} 

W android.index.js Dzwonię metody rodzimej, jak pokazano poniżej:

/** 
* 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); 

Ale w kodzie java podczas zwrotu applist (successCallback.invoke (applist);) otrzymuję powyższy błąd.

czy możesz mi pomóc, gdzie robię źle. Dzięki

Szczegółowe Błąd:

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

Podczas pracy Native mosty, wywołania zwrotne powinny być wywołany z WritableNative komponentów z pakietu com.facebook.react.bridge.

Zamiast JSONObject użyj WritableNativeMap.
Zamiast JSONArray użyj WritableNativeArray.

Na przykład, z WritableNativeMap:

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

    onSuccessCallback(resultData); 
} 

W twoim przypadku, trzeba mieć coś takiego:

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()); 
    } 
}