package com.android.app;

import android.app.Activity;
import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast; 

public class Main extends Activity {
 private boolean isopent = false;
 private Camera camera; 

 @Override

 protected void onCreate(Bundle savedInstanceState) {
  // TODO Auto-generated method stub
  super.onCreate(savedInstanceState);
  View view = View.inflate(this, R.layout.main, null);
  setContentView(view);
  TextView img_but = (TextView) findViewById(R.id.main_img);
  img_but.setOnClickListener(new View.OnClickListener() {

   @Override
   public void onClick(View v) {
    // TODO Auto-generated method stub
    if (!isopent) {
     Toast.makeText(getApplicationContext(), "您已经打开了手电筒", 0)
       .show();
     camera = Camera.open();
     Parameters params = camera.getParameters();
     params.setFlashMode(Parameters.FLASH_MODE_TORCH);
     camera.setParameters(params);
     camera.startPreview(); // 开始亮灯

     isopent = true;

    } else {
     Toast.makeText(getApplicationContext(), "关闭了手电筒",
       Toast.LENGTH_SHORT).show();
     camera.stopPreview(); // 关掉亮灯
     camera.release(); // 关掉照相机
     isopent = false;

    }

   }

  });

 }

 

}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="<a href="http://schemas.android.com/apk/res/android"" rel="nofollow" target="_blank">http://schemas.android.com/apk/res/android"</a>
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical" >
 
 <TextView
  android:id="@+id/main_img"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:background="@drawable/main_body">
 </TextView>

</LinearLayout>

<manifest xmlns:android="<a href="http://schemas.android.com/apk/res/android"" rel="nofollow" target="_blank">http://schemas.android.com/apk/res/android"</a>
 package="com.android.app"
 android:versionCode="1"
 android:versionName="1.0" > 

 <uses-sdk
  android:minSdkVersion="8"
  android:targetSdkVersion="15" />
 <application
  android:icon="@drawable/ic_launcher"
  android:label="@string/app_name"
  android:theme="@style/AppTheme" >
  <activity android:name=".AppStart" >
   <intent-filter>
    <action android:name="android.intent.action.MAIN" />

 

    <category android:name="android.intent.category.LAUNCHER" />
   </intent-filter>
  </activity>
  <activity android:name=".Main" >
  </activity>
 </application>
 <!-- 摄像头、手电筒 -->
 <uses-permission android:name="android.permission.CAMERA" />
 <uses-permission android:name="android.permission.FLASHLIGHT" />

 <uses-feature android:name="android.hardware.camera" />
 <uses-feature android:name="android.hardware.camera.autofocus" />
 <uses-feature android:name="android.hardware.camera.flash" />
 

</manifest>