android - Intent from sensor listener within application class

Question

I am trying to include shake functionality in my app. For that i require to intent an activity upon phone shake irrespective of where the user is in the application. Now i placed my sensor code in the application class but in order to intent it requires context. Am i on a right way or is there any other way to achieve this functionality ? Here's my code

public class MyApplication extends Application {


/* variables for shake detection */
private SensorManager mSensorManager;
private float mAccel; // acceleration apart from gravity
private float mAccelCurrent; // current acceleration including gravity
private float mAccelLast; // last acceleration including gravity
@Override
public void onCreate(){

    /* sensor shake detection */
  mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
    mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
    mAccel = 0.00f;
    mAccelCurrent = SensorManager.GRAVITY_EARTH;
    mAccelLast = SensorManager.GRAVITY_EARTH;   
}


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 > 3.0f)
      {
         // Toast.makeText(getBaseContext(), "Phone shaked", Toast.LENGTH_SHORT).show();
          Intent intent = new Intent(getApplicationContext(),LiveSearchActivity.class);
          startActivity(intent);


      }
    }

    public void onAccuracyChanged(Sensor sensor, int accuracy) {

    }

  };

}

Answer 1

您的课程正在扩展应用程序，而不是您应该扩展 Activity。

public class MyApplication extends Activity
{
    @Override
    protected void onCreate(Bundle Sumit)
    { 
        super.onCreate(Sumit);
    }    
}

Answer 2

试试这个代码。我已经检查过了。有效 。现在它会正确地重定向到你的手机震动后你想去的地方。希望它会帮助你。

package com.example.stack;

import android.app.Application;
import android.content.Context;
import android.content.Intent;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;

public class MyApplication extends Application {


/* variables for shake detection */
private SensorManager mSensorManager;
private float mAccel; // acceleration apart from gravity
private float mAccelCurrent; // current acceleration including gravity
private float mAccelLast; // last acceleration including gravity
Context context;
@Override
public void onCreate(){

    context=this;
    /* sensor shake detection */
  mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
    mSensorManager.registerListener(mSensorListener, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_NORMAL);
    mAccel = 0.00f;
    mAccelCurrent = SensorManager.GRAVITY_EARTH;
    mAccelLast = SensorManager.GRAVITY_EARTH;   
}


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 > 3.0f)
      {
         // Toast.makeText(getBaseContext(), "Phone shaked", Toast.LENGTH_SHORT).show();
          Intent intent = new Intent(context,MainActivity.class);
          intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);       

          startActivity(intent);


      }
    }

    public void onAccuracyChanged(Sensor sensor, int accuracy) {

    }

  };

}