Android手电筒

public class HandLightActivity extends Activity implements OnClickListener{
private ToggleButton toggleButton;
private Camera m_Camera;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.handlight);
toggleButton = (ToggleButton)this.findViewById(R.id.toggleButton1);
toggleButton.setOnClickListener(this);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
}
@Override
public void onClick(View v) {
ToggleButton tb = (ToggleButton)v;
if(!tb.isChecked()){
PackageManager pm= this.getPackageManager();
FeatureInfo[]  features=pm.getSystemAvailableFeatures();
for(FeatureInfo f : features)
{
  if(PackageManager.FEATURE_CAMERA_FLASH.equals(f.name))   //判断设备是否支持闪光灯
  {
  if ( null == m_Camera )  
    {  
        m_Camera = Camera.open();      
    }  


    Camera.Parameters parameters = m_Camera.getParameters();               
    parameters.setFlashMode(Camera.Parameters.FLASH_MODE_TORCH);    
    m_Camera.setParameters( parameters );              
    m_Camera.startPreview();
toggleButton.setBackgroundColor(0x30ffffff);
  }
}
}else{
if ( m_Camera != null )  
   {  
       m_Camera.stopPreview();  
       m_Camera.release();  
       m_Camera = null;  
   }
toggleButton.setBackgroundColor(0xffffffff);
}
}
} 


详细出处参考：http://www.jb51.net/article/38523.htm