关于Android串口编程求助

一条不更新的懒狗 2017-09-28 11:03:00

最近做android的串口开发，参考了网上的例子。和大家一样都是使用谷歌提供的串口实例。 http://code.google.com/p/android-serialport-api/ 导入后能正常的收发数据。

但是我做到多个Activity的时候，发现在接收数据的时候。接收数据的ReadThread不是当前Activity的ReadThread，而是前面的Activity的ReadThread。但是前面的Activity已经关闭了，所以造成数据丢失。请问如何解决:

我的Activity如下: 参考博客链接 http://blog.csdn.net/ckw474404603/article/details/37811499

public abstract class SerialPortActivity extends Activity {  

  

    protected Application mApplication;  

    protected SerialPort mSerialPort;  

    protected OutputStream mOutputStream;  

    private InputStream mInputStream;  

    private ReadThread mReadThread;  

  

    private class ReadThread extends Thread {  

  

        @Override  

        public void run() {  

            super.run();  

            while (!isInterrupted()) {  

                int size;  

                try {  

                    byte[] buffer = new byte[64];  

                    if (mInputStream == null) {  

                        return;  

                    }  

                    size = mInputStream.read(buffer);  

                    if (size > 0) {  

                        onDataReceived(buffer, size);  

                    }  

                } catch (IOException e) {  

                    e.printStackTrace();  

                    return;  

                }  

            }  

        }  

    }  

  

    private void DisplayError(int resourceId) {  

        AlertDialog.Builder b = new AlertDialog.Builder(this);  

        b.setTitle("Error");  

        b.setMessage(resourceId);  

        b.setPositiveButton("OK", new OnClickListener() {  

            public void onClick(DialogInterface dialog, int which) {  

                SerialPortActivity.this.finish();  

            }  

        });  

        b.show();  

    }  

  

    @Override  

    protected void onCreate(Bundle savedInstanceState) {  

        super.onCreate(savedInstanceState);  

        mApplication = (Application) getApplication();  

        try {  

            mSerialPort = mApplication.getSerialPort();  

            mOutputStream = mSerialPort.getOutputStream();  

            mInputStream = mSerialPort.getInputStream();  

  

            /* Create a receiving thread */  

            mReadThread = new ReadThread();  

            mReadThread.start();  

        } catch (SecurityException e) {  

            DisplayError(R.string.error_security);  

        } catch (IOException e) {  

            DisplayError(R.string.error_unknown);  

        } catch (InvalidParameterException e) {  

            DisplayError(R.string.error_configuration);  

        }  

    }  

  

    protected abstract void onDataReceived(final byte[] buffer, final int size);  

  

    @Override  

    protected void onDestroy() {  

        if (mReadThread != null)  

            mReadThread.interrupt();  

        mApplication.closeSerialPort();  

        mSerialPort = null;  

        super.onDestroy();  

    }  

}

...全文

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一条不更新的懒狗 2017-09-29

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引用 2 楼 alexxm_001 的回复:

SerialPortActivity.java中修改 protected void onDestroy() { if (mReadThread != null) { mReadThread.interrupt(); mReadThread.stop(); mReadThread=null; } mApplication.closeSerialPort(); mSerialPort = null; super.onDestroy(); }

Caused by: java.lang.UnsupportedOperationException at java.lang.Thread.stop(Thread.java:1052) at java.lang.Thread.stop(Thread.java:1042) at shangexi.baiheng.com.shangexi.base.SerialPortActivity.onStop(SerialPortActivity.java:130) 在stop这个地方异常了

一条不更新的懒狗 2017-09-29

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辉_alexxm 2017-09-29

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SerialPortActivity.java中修改 protected void onDestroy() { if (mReadThread != null) { mReadThread.interrupt(); mReadThread.stop(); mReadThread=null; } mApplication.closeSerialPort(); mSerialPort = null; super.onDestroy(); }

辉_alexxm 2017-09-29

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用服务的方式试下，以前我是关闭线程的，会提示错误，问题出在read 上，一直不退出；

一条不更新的懒狗 2017-09-29

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引用 5 楼 alexxm_001 的回复:

我找了下InputStream，换了一个方式，可以参考以下的内容 https://zhidao.baidu.com/question/577343889.html 我写的代码如下： while(!isInterrupted()) { int size; try { byte[] buffer = new byte[64]; if (mInputStream == null) return; int available=mInputStream.available(); if(available!=0) { size = mInputStream.read(buffer); if (size > 0) { onDataReceived(buffer, size); Log.v("SerialPortActivity", "ReadThread size:" + size); } } else { // Log.v("SerialPortActivity","available size:"+available); } } catch (IOException e) { e.printStackTrace(); return; } try { Thread.sleep(1); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } 这样要注意串口数据的串接问题，有问题时留意下！

感谢你的回答，我测试你的答案。在sleep这一行发生了异常,不过被抓取了:

09-29 14:18:58.687 26036-26349/com.huruwo.sportthread W/System.err: java.lang.InterruptedException
09-29 14:18:58.687 26036-26349/com.huruwo.sportthread W/System.err:     at java.lang.VMThread.sleep(Native Method)
09-29 14:18:58.687 26036-26349/com.huruwo.sportthread W/System.err:     at java.lang.Thread.sleep(Thread.java:1013)
09-29 14:18:58.697 26036-26349/com.huruwo.sportthread W/System.err:     at java.lang.Thread.sleep(Thread.java:995)
09-29 14:18:58.697 26036-26349/com.huruwo.sportthread W/System.err:     at com.huruwo.sportthread.Data1Activity$myThread.run(Data1Activity.java:150)
09-29 14:18:58.697 26036-26349/com.huruwo.sportthread W/System.err: java.io.IOException: ioctl failed: EBADF (Bad file number)
09-29 14:18:58.697 26036-26349/com.huruwo.sportthread W/System.err:     at libcore.io.IoBridge.available(IoBridge.java:68)
09-29 14:18:58.707 26036-26349/com.huruwo.sportthread W/System.err:     at java.io.FileInputStream.available(FileInputStream.java:110)
09-29 14:18:58.707 26036-26349/com.huruwo.sportthread W/System.err:     at com.huruwo.sportthread.Data1Activity$myThread.run(Data1Activity.java:130)
09-29 14:18:58.707 26036-26349/com.huruwo.sportthread W/System.err: Caused by: libcore.io.ErrnoException: ioctl failed: EBADF (Bad file number)
09-29 14:18:58.717 26036-26349/com.huruwo.sportthread W/System.err:     at libcore.io.Posix.ioctlInt(Native Method)
09-29 14:18:58.717 26036-26349/com.huruwo.sportthread W/System.err:     at libcore.io.ForwardingOs.ioctlInt(ForwardingOs.java:84)
09-29 14:18:58.717 26036-26349/com.huruwo.sportthread W/System.err:     at libcore.io.IoBridge.available(IoBridge.java:52)
09-29 14:18:58.727 26036-26349/com.huruwo.sportthread W/System.err: 	... 2 more

但是数据算是正确的传到了

辉_alexxm 2017-09-29

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我找了下InputStream，换了一个方式，可以参考以下的内容 https://zhidao.baidu.com/question/577343889.html 我写的代码如下： while(!isInterrupted()) { int size; try { byte[] buffer = new byte[64]; if (mInputStream == null) return; int available=mInputStream.available(); if(available!=0) { size = mInputStream.read(buffer); if (size > 0) { onDataReceived(buffer, size); Log.v("SerialPortActivity", "ReadThread size:" + size); } } else { // Log.v("SerialPortActivity","available size:"+available); } } catch (IOException e) { e.printStackTrace(); return; } try { Thread.sleep(1); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } } 这样要注意串口数据的串接问题，有问题时留意下！