PluginRegistry.ActivityResultListener: not triggered

[faspadaro]

Steps to Reproduce

1. Create a Flutter package in java
2. In plugin class add a Activity result listener
3. In onMethodCall call startActivityForResult
4. In Activity called, at a certain point, call setResult and finish

Issue is the `onActivityResult' plugin is not triggered when Activity child call finish.

here's the code of parent MyBarcodeScannerPlugin ...

    public class MyBarcodeScannerPlugin implements MethodCallHandler, PluginRegistry.ActivityResultListener {
      private final Activity activity;
      private Result result;

      public static void registerWith(Registrar registrar) {
        final MethodChannel channel = new MethodChannel(registrar.messenger(),    "my_barcode_scanner");

        final MyBarcodeScannerPlugin plugin = new MyBarcodeScannerPlugin(registrar.activity());

        channel.setMethodCallHandler(plugin);
        registrar.addActivityResultListener(plugin);
      }

      private MyBarcodeScannerPlugin(Activity activity) {
        this.activity = activity;
      }


      @Override
      public void onMethodCall(MethodCall call, Result result) {
        if (call.method.equals("scan")) {
          this.result = result;
          showBarcodeView(activity);
        } else {
          result.notImplemented();
        }
      }

      private void showBarcodeView(Activity activity) {
        Intent intent = new Intent(activity, MyBarcodeScannerActivity.class);
        activity.startActivityForResult(intent, 100);
      }

      @Override
      public boolean onActivityResult(int requestCode, int resultCode, Intent data) {
        // IT DOES NOT FIRE !
        if (requestCode == 100) {
          if (resultCode == Activity.RESULT_OK) {
            this.result.success("");
          } else {
            String errorCode = data.getStringExtra("ERROR_CODE");
            this.result.error(errorCode, null, null);
          }
          return true;
        }
        return false;
      }
    }

And here's the child activity that finish when user deny permission...

    public class MyBarcodeScannerActivity extends AppCompatActivity {
        ...
        ...
        private void finishWithError(String errorCode) {
            Intent intent = new Intent();
            intent.putExtra("ERROR_CODE", errorCode);
            setResult(Activity.RESULT_CANCELED, intent);
            finish();
        }
        ...
        public void onRequestPermissionsResult(int requestCode, String  permissions[], int[] grantResults) {
            switch (requestCode) {
                case REQUEST_CAMERA:
                    if (grantResults.length > 0) {
                        boolean cameraAccepted = grantResults[0] == PackageManager.PERMISSION_GRANTED;
                        if (cameraAccepted){
                        }else {
                            finishWithError("PERMISSION_NOT_GRANTED");
                        }
                    }
                    break;
            }
        }
    }

flutter doctor -v
[√] Flutter (Channel stable, v1.0.0, on Microsoft Windows [Versione 10.0.16299.904], locale it-IT)
    • Flutter version 1.0.0 at C:\dati\Flutter\flutter
    • Framework revision 5391447fae (8 weeks ago), 2018-11-29 19:41:26 -0800
    • Engine revision 7375a0f414
    • Dart version 2.1.0 (build 2.1.0-dev.9.4 f9ebf21297)

[√] Android toolchain - develop for Android devices (Android SDK 28.0.3)
    • Android SDK at C:/Users/...
    • Android NDK location not configured (optional; useful for native profiling support)
    • Platform android-28, build-tools 28.0.3
    • ANDROID_HOME = C:/Users/...
    • Java binary at: C:\dati\Android\Android Studio\jre\bin\java
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b02)

[√] Android Studio (version 3.1)
    • Android Studio at C:\dati\Android\Android Studio
    • Flutter plugin version 29.0.1
    • Dart plugin version 173.4700
    • Java version OpenJDK Runtime Environment (build 1.8.0_152-release-1024-b02)

[√] IntelliJ IDEA Community Edition (version 2018.1)
    • IntelliJ at C:\Program Files\JetBrains\IntelliJ IDEA Community Edition 2018.1.4
    • Flutter plugin version 25.0.2
    • Dart plugin version 181.4892.1

[√] VS Code, 64-bit edition (version 1.23.1)
    • VS Code at C:\Program Files\Microsoft VS Code
    • Flutter extension version 2.13.2

[√] Connected device (1 available)
    • Redmi Note 5 • 8614d893 • android-arm64 • Android 8.1.0 (API 27)

[zoechi]

The impage_picker and google_sign_in plugin seem to use that as well. Did you check how they do it?

• https://github.com/flutter/plugins/blob/9616a32faf6d1066c8f633a30f0bd7dca6fe7e9e/packages/image_picker/android/src/main/java/io/flutter/plugins/imagepicker/ImagePickerDelegate.java
• https://github.com/flutter/plugins/blob/d89cae7289ec4f7a51b6e7a17e3f0bb9498d0b19/packages/google_sign_in/android/src/main/java/io/flutter/plugins/googlesignin/GoogleSignInPlugin.java

[zoechi]

Please consider asking support questions in one of the other channels listed at http://flutter.io/support .

[faspadaro]

@zoechi

I checked barcode_scan plugin wirtten in kotlin, it is similar to my package

    class BarcodeScanPlugin(val activity: Activity): MethodCallHandler,
        PluginRegistry.ActivityResultListener {
      var result : Result? = null
      companion object {
        @JvmStatic
        fun registerWith(registrar: Registrar): Unit {
          val channel = MethodChannel(registrar.messenger(), "com.apptreesoftware.barcode_scan")
          val plugin = BarcodeScanPlugin(registrar.activity())
          channel.setMethodCallHandler(plugin)
          registrar.addActivityResultListener(plugin)
        }
      }

      override fun onMethodCall(call: MethodCall, result: Result): Unit {
        if (call.method.equals("scan")) {
          this.result = result
          showBarcodeView()
        } else {
          result.notImplemented()
        }
      }

      private fun showBarcodeView() {
        val intent = Intent(activity, BarcodeScannerActivity::class.java)
        activity.startActivityForResult(intent, 100)
      }

      override fun onActivityResult(code: Int, resultCode: Int, data: Intent?): Boolean {
        if (code == 100) {
          if (resultCode == Activity.RESULT_OK) {
            val barcode = data?.getStringExtra("SCAN_RESULT")
            barcode?.let { this.result?.success(barcode) }
          } else {
            val errorCode = data?.getStringExtra("ERROR_CODE")
            this.result?.error(errorCode, null, null)
          }
          return true
        }
        return false
      }
    }


    class BarcodeScannerActivity : Activity(), ZXingScannerView.ResultHandler {
        ...
        fun finishWithError(errorCode: String) {
                val intent = Intent()
                intent.putExtra("ERROR_CODE", errorCode)
                setResult(Activity.RESULT_CANCELED, intent)
                finish()
            }
        ...
    }

[faspadaro]

Is there any update on this issue?

[yxwandroid]

I have the same problem

[function1983]

google_sign_in 4.0.1+3 has the same problem

Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel dev, v1.5.8, on Linux, locale en_US.UTF-8)
 
[✓] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[✓] Android Studio (version 3.4)
[!] VS Code (version 1.33.1)
    ✗ Flutter extension not installed; install from
      https://marketplace.visualstudio.com/items?itemName=Dart-Code.flutter
[✓] Connected device (1 available)

[rmarau]

I landed here searching a plugin design guideline to deal with duplicate Request Codes across android plugins.
It happened to me (and possibly @faspadaro 's as well) having barcode_scan in the project and designing a plugin that uses the same intent request code = 100.

They conflict! And barcode_scan is taking the lead in the delegation queue.

Changing the Request Code solved my issue.

Now this brings me to another topic. How to guarantee that plugins in pub.dev will not have identical request codes? (without randomly typing the num keyboard)

My suggestion would be to recommend every plugin to use android's intents to register an xml id and using it via R.id.mypluginrequestcode. The sdk handles uniqueness when integrating each plugin to the same project. No overhead.

@zoechi , sounds reasonable?

Even better: the flutter plugin template creating the id resource from the beginning.

[guzishiwo]

I landed here searching a plugin design guideline to deal with duplicate Request Codes across android plugins.
It happened to me (and possibly @faspadaro 's as well) having barcode_scan in the project and designing a plugin that uses the same intent request code = 100.

They conflict! And barcode_scan is taking the lead in the delegation queue.

Changing the Request Code solved my issue.

Now this brings me to another topic. How to guarantee that plugins in pub.dev will not have identical request codes? (without randomly typing the num keyboard)

My suggestion would be to recommend every plugin to use android's intents to register an xml id and using it via R.id.mypluginrequestcode. The sdk handles uniqueness when integrating each plugin to the same project. No overhead.

@zoechi , sounds reasonable?

Even better: the flutter plugin template creating the id resource from the beginning.

Very Good !!!!! Solve my question

[longdw]

faced the same problem. there is no solution so far.

[muthufmass]

I am facing same issue, I found even after we registrar.addActivityResultListener(this) on the plugin, still if you go to the MainActivity of the project which uses our plugin and add an override for onActivityResult, you will find the result reaching there , instead of listener in the plugin class object. Need some help here.