java - 使用广播在摇晃时启动应用程序

Question

我想要的是，当我的应用程序在后台运行并且我摇动手机时，应用程序应该启动并进入前台!

为了实现这一目标，我使用了广播接收器，如下所示:

public class BootReceiver extends BroadcastReceiver {

        @Override
        public void onReceive(Context arg0, Intent arg1) {
            // TODO Auto-generated method stub
             mSensorManager = (SensorManager) arg0.getSystemService(arg0.SENSOR_SERVICE);
               mSensorManager.registerListener( mSensorIntentListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
        }

    }

我也注册了它，如下:

<receiver 

             android:name=".BootReceiver">
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED" />
                 <action android:name="android.intent.action.QUICKBOOT_POWERON" />
            </intent-filter>
    </receiver>

现在对于摇动事件，我使用如下代码:

private final SensorEventListener mSensorIntentListener = new SensorEventListener() {

            public void onSensorChanged(SensorEvent se) {
              float x = se.values[0];
              float y = se.values[1];
              float z = se.values[2];
              mAccelLast = mAccelCurrent;
              mAccelCurrent = (float) Math.sqrt((double) (x*x + y*y + z*z));
              float delta = mAccelCurrent - mAccelLast;
              mAccel = mAccel * 0.9f + delta; // perform low-cut filter
              if (mAccel > 12) {
                     Toast.makeText(getApplicationContext(), "Device has shaken.", Toast.LENGTH_LONG).show();
                     Intent intent = new Intent(getApplicationContext(), MainActivity.class)
                                .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                            startActivity(intent);
              }

            }

            @Override
            public void onAccuracyChanged(Sensor arg0, int arg1) {
                // TODO Auto-generated method stub

            }


     };

现在，当我尝试运行应用程序并将其置于后台并摇动时，它不起作用!

那么逻辑错误是什么以及如何使我的应用程序在抖动时进入前台？

还有一件事我正在使用嵌套类概念，因此所有类都在 MainActivity 类中!

代码已满!:

package com.example.sensorlist;



public class MainActivity extends ActionBarActivity {
     TextView tv1=null;
     static File file = null;
     private String outputFile = null;
      private float mAccel; // acceleration apart from gravity
      private float mAccelCurrent; // current acceleration including gravity
      private float mAccelLast; // last acceleration including gravity
      Button play,stop,record;
      MediaRecorder myAudioRecorder;
       public SensorManager mSensorManager;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
         play=(Button)findViewById(R.id.button3);
          stop=(Button)findViewById(R.id.button2);
          record=(Button)findViewById(R.id.button);


         stop.setEnabled(false);
          play.setEnabled(false);

          final File path =
                Environment.getExternalStoragePublicDirectory
                (
                    //Environment.DIRECTORY_PICTURES
                    //Environment.DIRECTORY_DCIM
                    Environment.DIRECTORY_DCIM + "/Utkarshrecord/"
                );

            // Make sure the sound directory exists.
            if(!path.exists())
            {
                path.mkdirs();
            }

           try {
             file=  File.createTempFile("sound", ".3gp", path);

            myAudioRecorder=new MediaRecorder();
            myAudioRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
            myAudioRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
            myAudioRecorder.setOutputFile(file.getAbsolutePath());

        } catch (IOException e2) {
            // TODO Auto-generated catch block
            e2.printStackTrace();
        }





          mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
          myAudioRecorder.setAudioEncoder(MediaRecorder.OutputFormat.AMR_NB);

        if( mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER)!=null){
            Toast.makeText(getBaseContext(), "Yes it is there ", Toast.LENGTH_LONG).show();
        }else{
            Toast.makeText(getBaseContext(), "Sry no accelerometer", Toast.LENGTH_LONG).show();
        }
        mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
        mAccel = 0.00f;
        mAccelCurrent = SensorManager.GRAVITY_EARTH;
        mAccelLast = SensorManager.GRAVITY_EARTH;
        record.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
                try {
                   myAudioRecorder.prepare();
                   myAudioRecorder.start();
                }

                catch (IllegalStateException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
                }

                catch (IOException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
                }

                record.setEnabled(false);
                stop.setEnabled(true);

                Toast.makeText(getApplicationContext(), "Recording started", Toast.LENGTH_LONG).show();
             }
          });
        stop.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) throws IllegalArgumentException,SecurityException,IllegalStateException {
                try{
                     myAudioRecorder.stop();
                    myAudioRecorder.release();
                    myAudioRecorder  = null;




                }catch(Exception e){
                    e.printStackTrace();
                }
                Toast.makeText(getApplicationContext(), "Audio recorded successfully",Toast.LENGTH_LONG).show();
                stop.setEnabled(false);
                play.setEnabled(true);
             }
          });
        play.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) throws IllegalArgumentException,SecurityException,IllegalStateException {
                MediaPlayer m = new MediaPlayer();

                try {
                   m.setDataSource(file.getAbsolutePath());
                   m.prepare();
                }

                catch (IOException e) {
                   e.printStackTrace();
                }



                m.start();
                Toast.makeText(getApplicationContext(), "Playing audio", Toast.LENGTH_LONG).show();
             }
          });

    }


     private final SensorEventListener mSensorListener = new SensorEventListener() {

            public void onSensorChanged(SensorEvent se) {
              float x = se.values[0];
              float y = se.values[1];
              float z = se.values[2];
              mAccelLast = mAccelCurrent;
              mAccelCurrent = (float) Math.sqrt((double) (x*x + y*y + z*z));
              float delta = mAccelCurrent - mAccelLast;
              mAccel = mAccel * 0.9f + delta; // perform low-cut filter
              if (mAccel > 12) {
                     Toast.makeText(getApplicationContext(), "Device has shaken.", Toast.LENGTH_LONG).show();
                    try {
                        myAudioRecorder.prepare();
                          myAudioRecorder.start();
                            record.setEnabled(false);
                            stop.setEnabled(true);

                    } catch (IllegalStateException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }

                       Toast.makeText(getBaseContext(), "recording has started", Toast.LENGTH_SHORT).show();

                }
            }

            @Override
            public void onAccuracyChanged(Sensor arg0, int arg1) {
                // TODO Auto-generated method stub

            }


     };
     private final SensorEventListener mSensorIntentListener = new SensorEventListener() {

            public void onSensorChanged(SensorEvent se) {
              float x = se.values[0];
              float y = se.values[1];
              float z = se.values[2];
              mAccelLast = mAccelCurrent;
              mAccelCurrent = (float) Math.sqrt((double) (x*x + y*y + z*z));
              float delta = mAccelCurrent - mAccelLast;
              mAccel = mAccel * 0.9f + delta; // perform low-cut filter
              if (mAccel > 12) {
                     Toast.makeText(getApplicationContext(), "Device has shaken.", Toast.LENGTH_LONG).show();
                     Intent intent = new Intent(getApplicationContext(), MainActivity.class)
                                .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                            startActivity(intent);
              }

            }

            @Override
            public void onAccuracyChanged(Sensor arg0, int arg1) {
                // TODO Auto-generated method stub

            }


     };

     @Override
      protected void onPause() {
        mSensorManager.unregisterListener(mSensorListener);
        super.onPause();
      }
     @Override
      protected void onResume() {
        super.onResume();
        mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
      }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
    public class ShakeRec extends Service{

        @Override
        public IBinder onBind(Intent arg0) {
            // TODO Auto-generated method stub
            return null;
        }

        @Override
        public void onCreate() {
            // TODO Auto-generated method stub
            super.onCreate();


        }



        @Override
        public void onDestroy() {
            // TODO Auto-generated method stub
            super.onDestroy();

        }

        @Override
        public int onStartCommand(Intent intent, int flags, int startId) {
            // TODO Auto-generated method stub

            return super.onStartCommand(intent, flags, startId);
        }



    }

    public class BootReceiver extends BroadcastReceiver {

        @Override
        public void onReceive(Context arg0, Intent arg1) {
            // TODO Auto-generated method stub
             mSensorManager = (SensorManager) arg0.getSystemService(arg0.SENSOR_SERVICE);
               mSensorManager.registerListener( mSensorIntentListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
        }

    }


}

Answer 1

您的<receiver>元素将不起作用。如果您在重新启动时查看 LogCat，您会看到来自 Android 的警告或错误，指出它找不到您的 BootReceiver类(class)。 list 注册的接收器不能是 Activity 内的嵌套类。

摆脱<receiver>元素。摆脱BootReceiver 。注册您的SensorEventListener在onCreate()您的 Activity 。只要您的进程正在运行(可能不会很长)，并且只要设备打开，您就应该收到传感器事件。