如何從onResume訪問陀螺儀？

Question

我有一些代碼旨在計算用戶轉多快的次數。我實現了一個陀螺儀，並在Resume上有一些代碼工作，以收集數據以及一些語音輸出。但是，我有問題讓陀螺儀在onResume中正常工作。首先，語音輸出無法正常工作，並且出現故障。接下來，我仍然沒有獲得陀螺儀的價值。

package com.example.shivamgandhi.gyrosafe; 

import android.content.Context; 
import android.content.Intent; 
import android.hardware.Sensor; 
import android.hardware.SensorEvent; 
import android.hardware.SensorEventListener; 
import android.hardware.SensorManager; 
import android.os.Bundle; 
import android.view.MotionEvent; 
import android.view.View; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.RelativeLayout; 
import android.widget.TextView; 

public class Balance_Test_Activity extends VoiceControl implements View.OnClickListener, SensorEventListener, View.OnTouchListener { 

    int n = 2; 
    Button btnarray[] = new Button[n]; 
    private SensorManager mSensorManager; 
    private Sensor default_gyro; 
    private TextView textView79; 
    RelativeLayout RelativeLayout; 
    int count1 = 0; 
    float axisX, axisY, axisZ; 
    double omegaMagnitude; 
    EditText ed29; 
    private static final float NS2S = 1.0f/1000000000.0f; 
    private final float[] deltaRotationVector = new float[4]; 
    int touch = 0; 

    int count2 = 0; 
    int time1 = 0; 
    int time2 = 0; 

    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.balance_test); 

     RelativeLayout = (RelativeLayout)findViewById(R.id.RelativeLayout4); 

     btnarray[0] = (Button)findViewById(R.id.button10); 
     btnarray[1] = (Button)findViewById(R.id.button20); 

     mSensorManager = (SensorManager)getSystemService(Context.SENSOR_SERVICE); 
     default_gyro = mSensorManager.getDefaultSensor(Sensor.TYPE_GYROSCOPE); 

     textView79 = (TextView)findViewById(R.id.textView79); 

     ed29 = (EditText)findViewById(R.id.editText29); 

     for(int i = 0; i <n; i++){ 
      btnarray[i].setOnClickListener(this); 
     } 

     RelativeLayout.setOnTouchListener(this); 

    } 

    //when this Activity starts 
    @Override 
    protected void onResume() 
    { 
     super.onResume(); 

     if (touch == 1){ 
      try{ 
       speakWords("Please place your hands on your hips and keep your feet under your shoulders. Hold your balance for the next 20 seconds"); 
       Thread.sleep(2000); 
       while(time1 < 334){ 
        mSensorManager.registerListener(this, default_gyro, SensorManager.SENSOR_DELAY_UI); 
        if(omegaMagnitude > 2){ 
         count1 ++; 
         time1 ++; 
        } 
        else{ 
         time1 ++; 
        } 
       } 
       Thread.sleep(2000); 
       speakWords("Place your hands by your side. Tap to continue."); 
       Thread.sleep(1000); 
       touch = 10; 
      } 
      catch(InterruptedException e){ 
       e.printStackTrace(); 
      } 
     } 

     if (touch == 2){ 
      speakWords("Please place your hands on your hips and stand on your nondominant foot for the next 20 seconds"); 
      while(time2 < 334){ 
       mSensorManager.registerListener(this, default_gyro, SensorManager.SENSOR_DELAY_UI); 
       if(omegaMagnitude > 2){ 
        count2 ++; 
        time1 ++; 
       } 
       else{ 
        time1 ++; 
       } 
      } 
      speakWords("You may resume normal stance now"); 
      touch = 20; 
     } 


    } 

    @Override 
    protected void onStop() 
    { 
     //unregister the sensor listener 
     mSensorManager.unregisterListener(this); 
     super.onStop(); 
    } 

    @Override 
    public void onClick(View v){ 
     if(v == findViewById(R.id.button10)){ 
      Intent myIntent = new Intent(this, Results_Page_Activity.class); 
      startActivity(myIntent); 
     } 
    } 

    @Override 
    public boolean onTouch(View v, MotionEvent event){ 
     if(v == RelativeLayout){ 
      if(touch == 0){ 
       touch = 1; 
       onResume(); 
       return true; 
      } 
      else if (touch == 10){ 
       touch = 2; 
       onResume(); 
       return true; 
      } 
      return true; 
     } 
     else{ 
      return false; 
     } 
    } 

    @Override 
    public void onAccuracyChanged(Sensor arg0, int arg1) 
    { 
     //Do nothing. 
    } 


    public void onSensorChanged(SensorEvent event) { 
     // This timestep's delta rotation to be multiplied by the current rotation 
     // after computing it from the gyro sample data. 

     // Axis of the rotation sample, not normalized yet. 
     float axisX = event.values[0]; 
     float axisY = event.values[1]; 
     float axisZ = event.values[2]; 

     // Calculate the angular speed of the sample 
     double omegaMagnitude = Math.sqrt(axisX*axisX + axisY*axisY + axisZ*axisZ); 

     float[] deltaRotationMatrix = new float[9]; 
     SensorManager.getRotationMatrixFromVector(deltaRotationMatrix, deltaRotationVector); 

     textView79.setText("Gyro X (Roll) :" + Float.toString(event.values[2]) + "\n" + 
       "Gyro Y (Pitch) :" + Float.toString(event.values[1]) + "\n" + 
       "Gyro Z (Yaw) :" + Float.toString(event.values[0])); 
    } 
} 

我該如何解決這段代碼，以便我可以從陀螺儀中實際檢索到數值？在此先感謝:)

Answer 1

好的，這裏有幾個問題。

1）永不睡在onResume或UI線程中的任何其他地方。你不能這樣舉起來。最好這樣做會導致你看起來像你已經墜毀，在最壞的情況下，它會實際上由於看門狗而崩潰。它幾乎不會做你想做的事。

2）你從來沒有真正設置imegaMagnitude，因爲你擁有了它重新定義onSensorChanged

3）你不會看到正確的價值無論如何，因爲它不會被置位，直到onSensorChanged被調用。因爲這只是在UI線程上調用的，所以直到onResume完成後纔會調用它（參見1）。所以你的代碼永遠無法工作。

4）你不能自己調用​​onResume。只有框架被允許調用生命週期功能。自己這樣做會嚴重地搞砸了。

你的方法是完全不合適的。重寫您的邏輯以使用基於事件的處理和狀態機模式。此代碼不可挽回。