Question

我正在制作一款应用程序，在我的Android应用程序中使用无触摸手势关闭和关闭闪光灯。它打开就好了，但我无法让它关闭。在此先感谢您的帮助。

这是我的MainActivity.java

      package com.proximitysensorapp.primo.app;

    import android.hardware.Sensor;
    import android.hardware.SensorEvent;
    import android.hardware.SensorEventListener;
    import android.hardware.SensorManager;
    import android.os.Bundle;
    import android.app.Activity;
    import android.content.Intent;
    import android.widget.TextView;
    import java.io.IOException;
    import android.content.pm.PackageManager;
    import android.hardware.Camera;
    import android.hardware.Camera.Parameters;
    import android.util.Log;
    import android.view.SurfaceHolder;
    import android.view.SurfaceHolder.Callback;
    import android.view.SurfaceView;
    import android.view.View;
    public class MainActivity extends Activity implements SensorEventListener, Callback 
   {
   SensorManager sm;
   Sensor s;
   TextView et1;
   Intent Activitynew;
   Camera camera;
   SurfaceView surfaceView;
   SurfaceHolder surfaceHolder; 
   public void TurnOn(View view) 
   {
   if (FlashAvailable() && camera != null) 
   {
   Parameters p = camera.getParameters();
   p.setFlashMode(Parameters.FLASH_MODE_TORCH);
   camera.setParameters(p);
   //camera.startPreview();
   try 
   {
   camera.setPreviewDisplay(surfaceHolder);
   } 
   catch (IOException e) {
   e.printStackTrace();
   }            
   }
   }
   public void TurnOff(View view) {
   if (FlashAvailable() && camera != null) {
   Parameters p = camera.getParameters();
   p.setFlashMode(Parameters.FLASH_MODE_OFF);
   camera.setParameters(p);
   //camera.stopPreview();          
   }
   }
   @SuppressWarnings("deprecation")
   @Override
   protected void onCreate(Bundle savedInstanceState) 
   {
   super.onCreate(savedInstanceState);
   setContentView(R.layout.activity_main);
   sm = (SensorManager) getSystemService(SENSOR_SERVICE);
   s = sm.getDefaultSensor(Sensor.TYPE_PROXIMITY);
   sm.registerListener(this, s, SensorManager.SENSOR_DELAY_NORMAL);
   Activitynew = new Intent(MainActivity.this, Activity2.class);
   surfaceView = (SurfaceView) this.findViewById(R.id.surface1);
   surfaceHolder = surfaceView.getHolder();
   surfaceHolder.addCallback(this);
   surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
   }
   @Override
   public void onResume() 
   {
  super.onResume();
  try {
  camera = Camera.open();     
  } catch (Exception e) {
  //---exception handling here---
  Log.d("Flashlight", e.toString());
  }
  }

  @Override
  public void onPause() {
  super.onPause();
  TurnOff(null);
  camera.release();
  }


  private Boolean FlashAvailable() {
  return getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH);
  }


  @Override
  public void onAccuracyChanged(Sensor arg0, int arg1) 
  {

  }
  @Override
  public void onSensorChanged(SensorEvent event) 
  {
  if (event.sensor.getType() == Sensor.TYPE_PROXIMITY) 
  {
  int temp = (int) event.values[0];

  if (temp==1)
  {
  TurnOff(null);
  }
  else if (temp==0)
  {
  TurnOn(null);
  }
  }
  }

  @Override
  public void surfaceCreated(SurfaceHolder holder) {
  // TODO Auto-generated method stub

  }

  @Override
  public void surfaceChanged(SurfaceHolder holder, int format, int width,
  int height) {
  // TODO Auto-generated method stub

  }

  @Override
  public void surfaceDestroyed(SurfaceHolder holder) {
  // TODO Auto-generated method stub

  }
  }

Answer 1

你应该添加

mCamera.stopPreview();
mCamera.release();

在你的关闭方法中

Android手电筒无法关闭

1 个答案: