手电筒源码

一个简单的用闪光灯作为手电筒功能的实现。

布局文件main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 
    android:orientation="vertical" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent"
  xmlns:android="http://schemas.android.com/apk/res/android">

    <!--背景图-->
    <ImageView 
        android:id="@id/image_bg" 
        android:layout_width="fill_parent" 
        android:layout_height="fill_parent" 
        android:src="@drawable/close" />

  <!--开关图片-->
    <ImageView 
        android:id="@id/image_onoff" 
        android:layout_width="80.0dip" 
        android:layout_height="80.0dip" 
        android:layout_marginBottom="46.0dip" 
        android:layout_alignParentBottom="true" 
        android:layout_centerHorizontal="true" />
</RelativeLayout>

Activity类

package com.wellss.flashlight;

import android.app.Activity;
import android.app.KeyguardManager;
import android.app.KeyguardManager.KeyguardLock;
import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.view.WindowManager;
import android.widget.ImageView;

public class FlashlightActivity extends Activity implements OnClickListener{

	private String TAG = "FlashlightAcitvity";
	  private Camera camera = null;
	  private ImageView mImageBg;
	  private ImageView mImageOnoff;  
	  private void updateBgImage()
	  {
	    if (IsFlashlightOn()){
		      this.mImageBg.setImageResource(R.drawable.open); 	
	    }
	    else{
	      this.mImageBg.setImageResource(R.drawable.close);
	    }
	   }
	  private boolean IsFlashlightOn(){
		  boolean isOn=false;
		  if(camera!=null)
		  {
			  Parameters parameters=camera.getParameters();
			  String flashLightModeString=parameters.getFlashMode();
			  if(flashLightModeString.equals(Parameters.FLASH_MODE_TORCH))
			  {
				  isOn=true;
			  }
			  else {
				  {
					  isOn=false;
				  }
			}
		  }
		  else {
			  {
				  isOn=false;
			  }
		}
		  return isOn;
	  }
	  private void SetFlashlightOn(){
		  if(camera!=null){
	          Parameters params = camera.getParameters();
	          params.setFlashMode(Parameters.FLASH_MODE_TORCH);
	          camera.setParameters(params);			  
		  }
	  }
	  private void SetFlashlightOff(){
		  if(camera!=null){
    		Parameters params=camera.getParameters();
    		params.setFlashMode(Parameters.FLASH_MODE_OFF);
    		camera.setParameters(params);
		  }
	  }
	  @Override
	public void onClick(View paramView) {
		// TODO Auto-generated method stub
		    if (paramView.getId() == R.id.image_onoff)
		    {
		    	if(!IsFlashlightOn()){
	                SetFlashlightOn();
	                updateBgImage();
			    }
		    	else {
	                SetFlashlightOff();
	                updateBgImage();
				}
		    }
	}
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		//dislay full screen
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
		setContentView(R.layout.main);		
	    this.mImageBg = ((ImageView)findViewById(R.id.image_bg));
	    this.mImageOnoff = ((ImageView)findViewById(R.id.image_onoff));
	    this.mImageOnoff.setOnClickListener(this);
//	    this.mIsScreenLock = isLockScreen();

	    Log.d(TAG, "cly on create");
	}
	class OpenCameraThread implements Runnable{

		@Override
		public void run() {
			// TODO Auto-generated method stub
			//耗时比较长，故放在另外一个线程中处理
		    if(camera==null){
		          camera=Camera.open();	
		          camera.startPreview(); 
			    }
		}
		
	}
	@Override
	protected void onStart() {
		// TODO Auto-generated method stub
		super.onStart();
		Thread openCamera=new Thread(new OpenCameraThread());
		openCamera.start();
	    Log.d(TAG, "cly on start");
	}
	@Override
	protected void onStop() {
		// TODO Auto-generated method stub
		super.onStop();
		if(camera!=null){
			//update image
		    this.mImageBg.setImageResource(R.drawable.close);
	        camera.stopPreview(); // 关掉亮灯
	        camera.release(); // 关掉照相机
	        camera=null;
		}
	    Log.d(TAG, "cly on stop");
	}

	@Override
	protected void onResume() {
		// TODO Auto-generated method stub
		super.onResume();
	    Log.d(TAG, "cly on resume");
	}
	@Override
	protected void onDestroy() {
		// TODO Auto-generated method stub
		super.onDestroy();

	    Log.d(TAG, "cly on destroy");
	}
	
}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest android:versionCode="1" android:versionName="1.0" package="com.wellss.flashlight"
  xmlns:android="http://schemas.android.com/apk/res/android">
    <uses-permission android:name="android.permission.DISABLE_KEYGUARD" />
    <uses-permission android:name="android.permission.FLASHLIGHT" />
    <uses-permission android:name="android.permission.WAKE_LOCK" />
    <uses-permission android:name="android.permission.CAMERA" />
    <uses-feature android:name="android.hardware.camera" />
    <uses-feature android:name="android.hardware.autofocus"/>
       <uses-sdk android:minSdkVersion="10"/>
    <application 
        android:label="@string/app_name" 
        android:icon="@drawable/ic_launcher" 
        android:debuggable="true">
        <activity android:name=".FlashlightActivity" android:screenOrientation="portrait">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
</manifest>