如何在 FlutterActivity 上实现 onActivityResult 和 onNewIntent

Question

I would like to implement onActivityResult and onNewIntent on my Android native side of flutter app.

For example, I would like to be able to run "startActivityForResult", and open my app using a deep link.

My main activity is flutter, but I have some work I need to do on the native part.

Is there a way to accomplish this without writing an external plugin?

package com.test.flutter_app

import androidx.annotation.NonNull;
import io.flutter.embedding.android.FlutterActivity
import io.flutter.embedding.engine.FlutterEngine
import io.flutter.plugins.GeneratedPluginRegistrant

class MainActivity: FlutterActivity() {
    override fun configureFlutterEngine(@NonNull flutterEngine: FlutterEngine) {
        GeneratedPluginRegistrant.registerWith(flutterEngine);
    }
}

As I understand from the documentation , I need to use PluginRegistry.Registrar addActivityResultListener . But who is my Registrar? how can I get it/use it? Code examples would be much appreciated.

Answer 1

FlutterActivity is an activity so I guess you could add something like this:

Result mResult;

private void doStuff() {
    ...
    startActivityForResult(intent, INTENT_CODE);
}

@Override
public boolean onActivityResult(int requestCode, int resultCode, Intent intent) {
    ...
    mResult.success(null);
    return false;
}

Now you can use doStuff using a platformchannel

    new MethodChannel(getFlutterView(), MY_CHANNEL).setMethodCallHandler(
            (call, result) -> {
                if (call.method.equals("my_method")) {
                    mResult = result;
                    doStuff();
                }
            });

Answer 2

The FlutterActivity class implements the PluginRegistry interface. The PluginRegistry interface defines a method registrarFor which is what you want.

https://api.flutter.dev/javadoc/io/flutter/plugin/common/PluginRegistry.html#registrarFor-java.lang.String-

So in your MainActivity class, you can do this.registrarFor('plugin_name_here') to get the registrar.

I think that you'll then want to set up an EventChannel . In your onActivityResult and onNewIntent methods, you can use the EventChannel to send data from the Kotlin code to the Dart code.

Answer 3

No need to write a plugin, You can use MethodChannel for platform-specific code.

https://flutter.dev/docs/development/platform-integration/platform-channels

Answer 4

I use this way.

Create Channel

MethodChannel nativeChannel = new MethodChannel(MainApplication.flutterActivity.getFlutterView(), CHANNEL_NATIVE);
nativeChannel.setMethodCallHandler(new MethodCallHandler() {
    @Override
    public void onMethodCall(@NotNull MethodCall methodCall, @NotNull Result result) {
        if (methodCall.method == METHOD_SHOW_NATIVEVIEW) {
            Intent intent = new Intent(MainApplication.instance().getApplicationContext(), [YourActivityClass]);
            intent.putExtra(ARG_VIEW_NAME, [YourActivityClassName]);
            MainFlutterActivity.instance().startActivityForResult(intent, RESULT_ACTIVITY);
        }
    }
});
public void closeNativeView(String viewName, HashMap<String, Object> params) {
    HashMap<String, Object> arg = new HashMap<>();
    arg.put(ARG_VIEW_NAME, viewName);
    arg.put(ARG_PARAMS, params);
    nativeChannel.invokeMethod(METHOD_CLOSE_NATIVEVIEW, arg, null);
}

Override FlutterActivity

public class MainFlutterActivity extends FlutterActivity {
  @Override
  protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (requestCode == RESULT_ACTIVITY) {
      String viewName = "";
      HashMap<String, Object> params = new HashMap<String, Object>();

      if (data != null) {
        viewName = data.getStringExtra(ARG_VIEW_NAME);
        params = (HashMap<String, Object>) data.getSerializableExtra(ARG_PARAMS);
      }

      closeNativeView(viewName, params);
    }
  }
}

Answer 5

After some research and debate on this issue, ended up reviewing a class used on a plugin for just this purpose. Linker for Flutter implements a PluginRegistry.ActivityResultListener interface on the plugin class, effectively allowing you to do what you are looking for. Check it out here:

Linker