如何在 SEservice 中使用 Executor (Open Mobile API for Android 9.0)

Question

我正在研究 NFC，目前正在尝试为 Android 9.0 中内置的 Open Mobile API 编写代码，但不了解在 SEService 中传递 Executor 参数的方式。

public class MainActivity extends Activity implements SEService.OnConnectedListener {

    final String LOG_TAG = "NfcTest";

    private SEService seService;

    private Button button;


    @Override
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        LinearLayout layout = new LinearLayout(this);
        layout.setLayoutParams(new LayoutParams(
                LayoutParams.WRAP_CONTENT,
                LayoutParams.WRAP_CONTENT));

        button = new Button(this);
        button.setLayoutParams(new LayoutParams(
                LayoutParams.WRAP_CONTENT,
                LayoutParams.WRAP_CONTENT));

        button.setText("Click Me");
        button.setEnabled(false);
        button.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                try {

                    Reader[] readers = seService.getReaders();
                    if (readers.length < 1)
                        return;


                    Session session = readers[0].openSession();



                    Channel channel = session.openLogicalChannel(new byte[]{
                            (byte) 0xF0, 0x51, (byte) 0xBC, 0x53, 0x54, 0x69, 0x64,
                            (byte) 0x4D, 0x6F, 0x62, 0x69, (byte) 0x6C,
                            (byte) 0x65, 0x2D, (byte) 0x49, 0x44});


                    byte[] respApdu = channel.transmit(new byte[]{
                            (byte) 0x90, 0x10, 0x00, 0x00, 0x00});

                    channel.close();

                    // Parse response APDU and show text but remove SW1 SW2 first
                    byte[] helloStr = new byte[respApdu.length - 2];
                    System.arraycopy(respApdu, 0, helloStr, 0, respApdu.length - 2);
                    Toast.makeText(MainActivity.this, new String(helloStr), Toast.LENGTH_LONG).show();
                } catch (Exception e) {
                    Log.i(LOG_TAG, "Message: " + e.getClass().getCanonicalName());
                    if(e.getClass().isInstance(new NoSuchElementException()))
                        Toast.makeText(MainActivity.this, "NFC sim", Toast.LENGTH_LONG).show();
                    else if (e.getClass().isInstance(new IOException())){
                        Toast.makeText(MainActivity.this, "No sim found", Toast.LENGTH_LONG).show();
                    }
                    else{
                        Toast.makeText(MainActivity.this, "Normal sim", Toast.LENGTH_LONG).show();
                    }
                }
            }
        });

        layout.addView(button);
        setContentView(layout);


        try {

            seService = new SEService(this, this,this);
        } catch (SecurityException e) {
            Log.e(LOG_TAG, "Binding not allowed, uses-permission org.simalliance.openmobileapi.SMARTCARD?");
        } catch (Exception e) {
            Log.e(LOG_TAG, "Exception: " + e.getMessage());
        }
    }

    @Override
    protected void onDestroy() {
        if (seService != null && seService.isConnected()) {
            seService.shutdown();
        }
        super.onDestroy();
    }

    public void serviceConnected(SEService service) {
        Log.i(LOG_TAG, "seviceConnected()");
        button.setEnabled(true);
    }

    @Override
    public void onConnected() {

    }
}

问题发生在：

seService = new SEService(this, this,this);

第一个和最后一个参数接受中间一个执行器出现错误！

java.util.concurrent.Executor this

如何通过这个？

Answer 1

您收到此错误是因为构造函数 SEService 的第二个参数必须是 java.util.concurrent.Executor。您的 MainActivity（this 对象）没有实现执行器。

SEService 使用此执行器调用回调方法。所以你必须自己创建这样一个执行器才能将它传递给SEService。例如，您可以简单地创建一个 ExecutorService 和一个工作线程来处理回调：

ExecutorService pool = Executors.newSingleThreadExecutor();
seService = new SEService(this, pool, this);

但请注意，这些回调随后会在工作线程（而不是应用程序的主线程）上执行。因此，如果您想从回调中执行任何 UI 操作，您需要在 UI 线程上显式运行它们，例如

runOnUiThread(new Runnable() {
    void run() {
        button.setEnabled(true); // ... or some other UI modifications
    }
});

如何在 SEservice 中使用 Executor (Open Mobile API for Android 9.0)

How to use Executor in SEservice (Open Mobile API for Android 9.0)

java

android

nfc

secure-element

open-mobile-api