带有抖动的Google Play许可验证库

Question

因此，我正在使用flutter进行应用程序开发（显然是标题），这是一款付费应用程序，因此需要验证许可证。我正在使用MedthodChannel来实现此目的，因为我无法自行解决。

现在的问题是： 因此，在Java方面，我正在检查许可证验证，然后将结果发送到flutter。这就是方法通道的工作方式。 但是问题在于，即使在验证完成之前，结果也会被发送到flutter，因此，哪个flutter部分认为许可证即使未通过验证也没有得到验证。

我在下面附加了Java辅助代码

    package in.navkargems.diamondtools;

    import android.os.Bundle;
    import android.os.Handler;
    import android.provider.Settings;
    import android.util.Log;

    import com.google.android.vending.licensing.LicenseChecker;
    import com.google.android.vending.licensing.LicenseCheckerCallback;
    import com.google.android.vending.licensing.StrictPolicy;

    import io.flutter.app.FlutterActivity;
    import io.flutter.plugin.common.MethodCall;
    import io.flutter.plugin.common.MethodChannel;
    import io.flutter.plugins.GeneratedPluginRegistrant;

    public class MainActivity extends FlutterActivity {

      private static final String CHANNEL = "in.navkargems.diamondtools/verify";

      private  static final String _key_to_verify_base64 = "MIIBIjAN...";

      private Handler mHandler;
      private LicenseChecker mChecker;
      private LicenseCheckerCallback mLicenseCheckerCallback;
      boolean licensed;
      boolean checkingLicense;
      boolean didCheck;
      int message = 0;

      @Override
      protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        GeneratedPluginRegistrant.registerWith(this);
        new MethodChannel(getFlutterView(), CHANNEL).setMethodCallHandler(
          new MethodChannel.MethodCallHandler() {
            @Override
            public void onMethodCall(MethodCall methodCall, MethodChannel.Result result) {
              if (methodCall.method.equals("verifyLicense")) {

                String deviceId = Settings.Secure.getString(getContentResolver(), Settings.Secure.ANDROID_ID);
                Log.i("Device Id", deviceId);

                mHandler = new Handler();
                mLicenseCheckerCallback = new MyLicenseCheckerCallback();
                mChecker = new LicenseChecker(getApplicationContext(), new StrictPolicy(), _key_to_verify_base64);
                doCheck();
                Log.i("License", "Check : "+didCheck);
                if(didCheck){
                  result.success(licensed);
                }
                else{
                  result.success(false);
                }
              }
            }
          }
        );
      }

      private void doCheck() {

        didCheck = false;
        checkingLicense = true;
        setProgressBarIndeterminateVisibility(true);
        mChecker.checkAccess(mLicenseCheckerCallback);

      }

      private class MyLicenseCheckerCallback implements LicenseCheckerCallback {

        @Override
        public void allow(int reason) {
          if(isFinishing()){
            Log.i("License", ""+isFinishing());
            return;
          }
          Log.i("License","Accepted!");
          message = 1;

          licensed = true;
          checkingLicense = false;
          didCheck = true;


        }

        @Override
        public void dontAllow(int reason) {
          if(isFinishing()){
            Log.i("License", ""+isFinishing());
            return;
          }
          Log.i("License", "Reason : "+reason);
          message = 0;
          licensed = false;
          checkingLicense = false;
          didCheck = true;

        }

        @Override
        public void applicationError(int errorCode) {
          Log.i("License", "Error : "+errorCode);
          if(isFinishing()){
            Log.i("License", ""+isFinishing());
            return;
          }
          message = 0;
          licensed = true;
          checkingLicense = false;
          didCheck = false;

        }

      }


    }

谢谢您的时间。