android闪关灯的开启和关闭方法代码实例

1、activity_main.xml 两个按钮，一个open一个close

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    tools:context=".MainActivity" >

    <TextView

        android:id="@+id/textView1"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:text="@string/hello_world" />
    <Button

        android:id="@+id/button_open"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_alignLeft="@+id/textView1"

        android:layout_below="@+id/textView1"

        android:layout_marginTop="38dp"

        android:text="open" />
    <Button

        android:id="@+id/button_close"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_alignLeft="@+id/button_open"

        android:layout_below="@+id/button_open"

        android:layout_marginTop="50dp"

        android:text="close" />
</RelativeLayout>

2、MainActivity 核心代码

package com.qiantu.flashlight;

import android.app.Activity;

import android.hardware.Camera;

import android.hardware.Camera.Parameters;

import android.os.Bundle;

import android.view.Menu;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;
public class MainActivity extends Activity {

 private Camera camera;

 private Button openBtn;

 private Button closeBtn;
 @Override

 protected void onCreate(Bundle savedInstanceState) {

  super.onCreate(savedInstanceState);

  setContentView(R.layout.activity_main);
  openBtn = (Button) findViewById(R.id.button_open);

  openBtn.setOnClickListener(new OnClickListener() {

   @Override

   public void onClick(View v) {

    if (null != camera) {

     Parameters parameters = camera.getParameters();

     parameters.setFlashMode(Parameters.FLASH_MODE_TORCH);

     camera.setParameters(parameters);

    }

   }

  });
  closeBtn = (Button) findViewById(R.id.button_close);

  closeBtn.setOnClickListener(new OnClickListener() {

   @Override

   public void onClick(View v) {

    if (null != camera) {

     Parameters parameters = camera.getParameters();

     parameters.setFlashMode(Parameters.FLASH_MODE_OFF);

     camera.setParameters(parameters);

    }

   }

  });

 }
 @Override

 protected void onStart() {

  super.onStart();

  camera = Camera.open();

 }
 @Override

 protected void onDestroy() {

  super.onDestroy();

  if (null != camera) {

   camera.release();

  }

 }
 @Override

 public boolean onCreateOptionsMenu(Menu menu) {

  getMenuInflater().inflate(R.menu.main, menu);

  return true;

 }
}

3、AndroidManifest.xml 加入摄像头和闪关灯的权限

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="com.qiantu.flashlight"

    android:versionCode="1"

    android:versionName="1.0" >

    <uses-sdk

        android:minSdkVersion="8"

        android:targetSdkVersion="18" />

    

    <!-- 添加的部分 -->

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

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

    <uses-permission android:name="android.permission.CAMERA" />

 <uses-permission android:name="android.permission.FLASHLIGHT" />

 <uses-permission android:name="android.permission.DISABLE_KEYGUARD" />

 <!-- end -->
    <application

        android:allowBackup="true"

        android:icon="@drawable/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme" >

        <activity

            android:name="com.qiantu.flashlight.MainActivity"

            android:label="@string/app_name" >

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

    </application>
</manifest>