android文档

Android 开发最佳实践从Futurice公司Android开发者中学到的经验。

遵循以下准则，避免重复发明轮子。

若您对开发iOS或Windows Phone 有兴趣，请看iOS Good Practices和Windows client Good Practices这两篇文章。

摘要•使用 Gradle 和它推荐的工程结构•把密码和敏感数据放在gradle.properties•不要自己写 HTTP 客户端,使用Volley或OkHttp库•使用Jackson库解析JSON数据•避免使用Guava同时使用一些类库来避免65k method limit（一个Android程序中最多能执行65536个方法）•使用 Fragments来呈现UI视图•使用 Activities 只是为了管理 Fragments•Layout 布局是 XMLs代码，组织好它们•在layoutout XMLs布局时，使用styles文件来避免使用重复的属性•使用多个style文件来避免单一的一个大style文件•保持你的colors.xml 简短DRY(不要重复自己)，只是定义调色板•总是使用dimens.xml DRY(不要重复自己)，定义通用常数•不要做一个深层次的ViewGroup•在使用WebViews时避免在客户端做处理，当心内存泄露•使用Robolectric单元测试，Robotium 做UI测试•使用Genymotion 作为你的模拟器•总是使用ProGuard 和 DexGuard混淆来项目Android SDK将你的Android SDK放在你的home目录或其他应用程序无关的位置。

当安装有些包含SDK的IDE的时候，可能会将SDK放在IDE同一目录下，当你需要升级（或重新安装）IDE或更换的IDE时，会非常麻烦。

此外，若果你的IDE 是在普通用户，不是在root下运行，还要避免吧SDK放到一下需要sudo权限的系统级别目录下。

Android2.2——API中文文档LLGYZB@目录：（1）—— TextView（2）—— EditText（3）—— AccessibilityService（4）—— Manifest（5）—— View（6）—— ImageView（7）—— ImageButton（8）—— QuickContactBadge（9）—— ZoomButton（10）—— CheckBox（11）—— RadioButton（12）—— Button（13）—— ToggleButton（14）—— ViewStub（15）——GridView一、TextView1、结构ng.Object↳android.view.View↳android.widget.TextView2、已知直接子类：Button, CheckedTextView, Chronometer, DigitalClock, EditText3、已知间接子类：AutoCompleteTextView, CheckBox, CompoundButton, ExtractEditText,MultiAutoCompleteTextView, RadioButton, ToggleButton二、EditText1、结构ng.Object↳ android.view.View↳android.widget.TextView↳ android.widget.EditText已知直接子类：AutoCompleteTextView, ExtractEditText已知间接子类： MultiAutoCompleteTextView2、xml 属性补充说明：a).由于是继承自TextView，所以属性是一样的，但是这里重点补充了输入法相关的属性说明和研究，部分注释也做了相应的调整。

b).Word格式下载/source/26641643、例子3.1<!--[endif]-->android:imeOptions例子<EditText android:id="@+id/txtTest" android:imeOptions="actionGo" android:layout_width="100dp" android:layout_height="wrap_con tent"></EditText>((EditText)findViewById(R.id.txtTest)).setOnEditorActionListener( new TextView.OnEditorActionListener() {@Overridepublic boolean onEditorAction(TextView v, int actionI d,KeyEvent event) {if (actionId == EditorInfo.IME_ACTION_GO) {Toast.makeText(TestActivity.this, "你点了Go!", Toast.LENGTH_SHORT).show();}return false;}});三、AccessibilityService1、结构ng.Object↳android.content.Context↳android.content.ContextWrapper↳android.app.Service↳android.accessibilityservice.AccessibilityServicepublic abstract class AccessibilityService extends Service2、类概述当AccessibilityEvent事件被启动后AccessibilityService 会接收回调函数运行于后台，这些事件指的是在用户接口间的状态转换，比如,焦点变化，按钮被点击等。

需求文档阐明书一、前语71.1项目介绍71.2名词解说71.3参阅资料8二、需求概述8三、用户特色83.1用户用例图83.2适用人群9四、假定和束缚8五、需求规矩85.1对功用的规矩85.2对功用的规矩95.3输入输出要求95.3数据办理能力要求95.3毛病处理要求95.3其它专门要求9六、功用结构图96.1功用介绍106.2功用事务总流程图10七、功用需求剖析107.1数据流图107.1.1顶层数据流图107.1.2功用级数据流图127.1.3具体数据流图157.2功用模块187.2.1事务功用描绘187.2.2事务流程图描绘187.2.3相关人物及其履行的活动18 7.2.4流程触及进程阐明187.2.5功用模块流程图197.2.6流程触及相关数据及规矩20八、体系运用的软件与硬件环境阐明428.1核心技能428.2硬件环境与服务器环境：428.3客户端操作体系：42九、原型界面42文档办理信息表主题版本内容规矩了项目事务处理进程和用户要求等信息。

关键字事务流程参阅文档无提交时刻创建人批阅人收效日期文档修正记载表修正人修正时刻修正内容一、前语1.1项目介绍项目称号：目的：缩写词：开发周期：1.2名词解说列出本文件中用到的专门术语的界说和外文首字母组词的原词组。

1.3参阅资料列出用得着的参阅资料，如：a．本项目的经核准的方案任务书或合同、上级机关的批文；b．归于本项目的其他已宣布的文件；本文件中遍地引证的文件、资料、包含所要用到的软件开发规范。

列出这些文件资料的标题、文件编号、宣布日期和出版单位，阐明能够得到这些文件资料的来历。

二、需求概述叙说该项软件开发的目的、运用方针、效果规划以及其他应向读者阐明的有关该软件开发的布景资料。

解说被开发软件与其他有关软件之间的联络。

假如本软件产品是一项独立的软件，而且全部内容自含，则阐明这一点。

假如所界说的产品是一个更大的体系的一个组成部分，则应阐明本产品与该体系中其他各组成部分之间的联络，为此可运用一张方框图来阐明该体系的组成和本产品同其他各部分的联络和接口。

android documentfile用法DocumentFile 是 Android 提供的一个用于处理文档文件的类，主要用于对文件进行 CRUD（增删改查）操作。

获取 DocumentFile 实例：1. 通过Storage Access Framework（存储访问框架）选择文件，返回一个 Uri 对象。

2. 通过 Uri 对象创建 DocumentFile 实例：```javaUri uri = ... // 从 Storage Access Framework 中选择文件后返回的 UriDocumentFile documentFile =DocumentFile.fromSingleUri(context, uri);```常用方法：1. 创建文件夹：```javaDocumentFile folder = parent.createDirectory("folder_name");```2. 创建文件：```javaDocumentFile file = parent.createFile("mime_type","file_name");```3. 删除文件或文件夹：```javaboolean deleted = documentFile.delete();```4. 获取文件的基本信息：```javaString name = documentFile.getName();String type = documentFile.getType();long size = documentFile.length();boolean isDirectory = documentFile.isDirectory();```5. 获取文件或文件夹的 Uri：```javaUri uri = documentFile.getUri();```6. 获取文件或文件夹的子项：```javaDocumentFile[] children = documentFile.listFiles();```7. 打开文件：```javaIntent intent = new Intent(Intent.ACTION_VIEW);intent.setDataAndType(uri, documentFile.getType()); intent.setFlags(Intent.FLAG_GRANT_READ_URI_PERMISSIO N);context.startActivity(intent);```8. 重命名文件或文件夹：```javaboolean renamed = documentFile.renameTo("new_name");```需要注意的是，DocumentFile 不支持直接操作文件的内容，比如写入文件内容。

本android帮助文档为在学习视频时自己制作比较混乱和粗糙，使用时查找第一页导航，再用word的查找功能进行查找导航页——基础说明——监听器的设置->创建监听器——调用android自带的短信发送功能——Activity的方法和生命周期（创建对话框风格的）——Activity的布局方法--LinearLayout线性--常用标签--TableLayout表格--GridView滑动表格--RelativeLayout相对布局——常用控件--除去title和全屏显示--EditText可输入文本框--RadioGroup和RadioButton单选按钮--Toast提示框--CheckBox多选按钮--ProgressBar进度条--ListView可选列表--MENU菜单控件的使用--Animation动画效果--4种动画效果--动画实现--JAVA中的实现--XMl文件中的实现-- Gallery （走马灯式的）移动选择控件--ImageSwitcher图片显示控件--ImageButton图片按钮控件--AlertDialog提示框——Handler的使用---线程--handler的简单应用--用handler更新ProgressBar进度条--handler与线程--线程之间的数据传递--Bundle对象（大量复杂数据） --Message对象（少量简单）--建立一个新的线程--HandlerThread类——SQLite的使用--SQLiteOpenHelper的方法注：带有下划线的是一些封装--代码的编写的可以直接调用的类，在”帮助文档的链接文件\封装的类”文件--封装的DatabaseHelper类夹中都有保存可以直接导入调用--主java文件--命令行的查询方法——文件下载--文件下载--步骤--在注册文件中注册权限--封装的HttpDownLoad类--在Activity中的调用--访问SDCARD --注册权限--封装的FileUtils类--在Activity文件中的调用——_XML文件的解析--SAX常用接口--XMl文件解析实例--实现ContentHandler接口的类--在Activity中的调用 XMl文件实例aaa.xml——广播机制--android中的广播机制--编写BroadcastReveicer类--创建包含BroadcastReveicer类的java文件--在onReceive中处理收到短消息的事件--AndroidManifest.XML注册文件中注册--代码当中进行注册--Activity中发送广播——WIFI--WIFI网卡的状态--操作WIFI网卡所需要的部分权限--改变WIFI网卡的状态——Socket编程--使用基于TCP协议的Socket--使用基于UDP协议的Socket——ServiceAndroid创建基础：src文件中为包类，其中用于建立activity的java文件res中drawable中为图片和标签layout中为布局文件，用于每个activity.java文件的标签布局AndroidManifest中为注册文件，每一个activity的建立都需要在其中注册代码的编写intent对象（用于在不同activity转换时的监听器设置）ponent name 指定activity2.Action 指定activity的作用3.Data 传送的数据类型4.Extras （额外）传送的键值对创建监听器的关键代码：（在第一个activity中）//创建一个Button监听器class myButtonListener implements OnClickListener{public void onClick(View v) {// TODO Auto-generated method stub//创建一个intent类Intent intent = new Intent();//创建一个键值对intent.putExtra("nexttext", "跳转成功");//创建关联intent.setClass(FirstActivity.this, SecondActivity.class);FirstActivity.this.startActivity(intent);}}在第一个activity中的转换关键标签上绑定监听器：（例在Button标签）（在onCreate中）//在Button上绑定监听器myButton.setOnClickListener(new myButtonListener());在第二个activity中的应用键值对（数据传递）：（在onCreate中）//获取键值对Intent intent = getIntent();//获得键值对的值String text = intent.getStringExtra("nexttext");在Activity中调用android自带的短信发送功能的关键代码：//调用短信发送功能class myButtonListener implements OnClickListener{public void onClick(View v) {// TODO Auto-generated method stub//发送号码Uri uri = Uri.parse("smsto://0800000123");Intent it = new Intent(Intent.ACTION_SENDTO,uri);//发送内容it.putExtra("sms_body", "the SMS text");startActivity(it);}}Activity的方法和生命周期：--onCreate 一个activity启动时运行（第一次）--onStart 当activity处于可见状态时运行--onResume 当activity可以得到用户焦点时（可以被操作）运行--onPause 当activity处于暂停状态时（例如弹出其他activity而原activity未被完全覆盖），可在此保存数据，以便此activity释放时恢复原状--onStop 当activity完全不可见时--onRestart 当activity未被销毁而在此被调用时--onDestory 当activity被销毁时当调用finish();语句时，Activity被销毁。

安卓开发 wps 原理一、WPS简介WPS，全称为Android WPS，是一款专为Android平台设计的办公软件。

它提供了丰富的文档处理功能，包括文字编辑、表格制作、演示文稿等，广泛应用于个人和商业场景。

安卓开发 wps 原理，即探讨安卓系统环境下WPS软件的开发原理和实现方式。

二、安卓开发基础安卓开发基于Java和Kotlin语言，使用Android SDK进行开发。

开发者可以使用Java和Kotlin编写应用程序代码，利用Android 提供的API和框架，开发出符合Android操作系统要求的应用程序。

WPS软件的开发过程中，需要利用Android SDK提供的API和框架，实现文档处理功能，同时遵循Android的安全性、稳定性、可扩展性等原则。

三、WPS软件原理1. 文档处理核心：WPS软件的核心功能是文档处理，涉及到文本编辑、格式转换、图片插入、表格制作等。

其实现原理主要是通过读取和写入文档文件，使用Java或Kotlin编写程序代码实现对文档的编辑和处理。

2. 用户界面设计：WPS软件的用户界面设计直接影响用户的使用体验。

其实现原理主要基于Android系统的UI框架，通过布局、样式、主题等设置，实现软件的界面设计。

3. 性能优化：安卓设备性能有限，WPS软件需要实现高效运行，包括内存管理、线程管理、性能优化等方面。

其实现原理主要通过优化代码、使用缓存技术、避免重复计算等方式，提高软件性能。

4. 跨平台支持：WPS软件需要支持多种不同的安卓设备，包括不同型号、不同配置的设备。

其实现原理主要通过适配不同的安卓版本、优化软件大小、兼容不同文件格式等方式，实现跨平台支持。

四、总结安卓开发 wps 的原理涉及到安卓开发基础、文档处理核心、用户界面设计、性能优化和跨平台支持等多个方面。

实现WPS软件需要充分利用Android SDK提供的API和框架，同时遵循Android的安全性、稳定性、可扩展性等原则，实现高效运行和跨平台支持。

Android中文文档:开发和调试在eclipse上开发Android应用程序在用eclipse IDE开发android应用程序之前，你首先要创建一个Android工程，并且建立一个启动配置，在此之后你才可以开始编写，运行，以及调试你的应用程序。

以下章节是假设你已经在eclipse环境中安装了ADT插件，如果你没有安装，请安装之后再使用以下说明。

参考安装eclipse 插件（ADT）创建一个android工程ADT提供了一个新的工程向导，你可以快速的创建一个新的工程或者在现有代码上创建工程。

创建工程的步骤如下：选择File > New > Project选择 Android > Android Project, 然后按下 Next选择项目内容:选择 Create new project in workspace，为编码创建一个全新的工程。

输入工程名称（project name），基础软件包的名称（the base package name），以及Activity 类的名称。

以创建stub .java文件等文件和程序名字。

选择Create project from existing source ，为已有代码创建一个工程。

如果你想编译运行SDK中提供的示例程序，可以使用这个选项。

示例程序的存放在SDK的samples/目录下。

浏览包含已有代码的目录，点击ok,如果目录中包含有可用的android manifest 文件，ADT 将为你填写合适的软件包，activity，和应用程序名称。

按下Finish.ADT插件会根据你的工程类型创建合适的文件和文件夹，如下:src/ 包含stub .java Activity文件的文件夹.res/ 资源文件夹.AndroidManifest.xml 工程清单.创建一个启动项能够在eclipse上运行调试应用程序之前，你必须为它创建一个启动项。

本文部分内容来自网络整理，本司不为其真实性负责，如有异议或侵权请及时联系，本司将立即删除！== 本文为word格式，下载后可方便编辑和修改！ ==android范例大全篇一：Google Android SDK开发范例大全(目录)第1章了解、深入、动手做 (1)1.1 红透半边天的Android (2)1.2 本书目的及涵盖范例范围 (3)1.3 如何阅读本书 (4)1.4 使用本书范例 (5)1.5 参考网站 (7)第2章 Android初体验 (8)2.1 安装Android SDK与ADT plug-in (9)2.2 建立第一个Android项目～Hello Android！ (10)2.3 Android应用程序架构—从此开始 (13)2.4 可视化的界面开发工具 (16)2.5 部署应用程序到Android手机 (17)第3章用户人机界面 (20)3.1 更改与显示文字标签——TextView标签的使用 (21)3.2 更改手机窗口画面底色——drawable定义颜色常数的方法 (23)3.3 更改TextView文字颜色——引用Drawable颜色常数及背景色 (25)3.4 置换TextView文字——CharSequence数据类型与Resource ID应用 (27)3.5 取得手机屏幕大小——DisplayMetrics取得画面宽高的方法 (29)3.6 样式化的定型对象——Style样式的定义 (31)3.7 简易的按钮事件——Button事件处理 (33)3.8 手机页面的转换——setContentView的应用 (35)3.9 调用另一个Activity——Intent对象的使用 (38)3.10 不同Activity之间的数据传递——Bundle对象的实现 (43)3.11 返回数据到前一个Activity——startActivityForResult方法 (47)3.12 具有交互功能的对话框——AlertDialog窗口 (52)3.13 置换文字颜色的机关——Button与TextView的交互 (54)3.14 控制不同的文字字体——Typeface对象使用 (56)3.15 如iPhone拖动相片特效——Gallery画廊 (59)3.16 自制计算器——多按钮的整合应用 (61)3.17 关于（About）程序信息——Menu功能菜单程序设计 (63)3.18 程序加载中～请稍后——ProgressDialog与线程整合应用 (66)3.19 全屏幕以按钮覆盖——动态产生按钮并最大化 (69)3.20 今晚到哪儿打牙祭？——具选择功能的对话框 (71)3.21 Android变脸——主题（Theme）实现 (74)第4章史上超豪华的手机控件 (77)4.1 EditText与TextView共舞——setOnKeyListener事件 (78)4.2 设计具有背景图的按钮——ImageButton的焦点及事件处理 (79)4.3 给耶诞老人的信息——Toast对象的使用 (83)4.4 我同意条款——CheckBox的isChecked属性 (85)4.5 消费券采购列表——多选项CheckBox的应用 (87)4.6 向左或向右——RadioGroup组与onCheckedChanged事件 (90)4.7 专业相框设计——ImageView的堆栈应用 (93)4.8 自定义下拉菜单模式——Spinner与setDropDownViewResource.. 964.9 动态添加/删除的Spinner菜单——ArrayList与Widget的依赖性......994.10 心爱小宝贝相片集——Gallery与衍生BaseAdapter容器 (103)4.11 快速的搜索手机文件引擎——Java I/O的应用 (106)4.12 按钮也能随点击变换——ImageButton选择特效 (109)4.13 具自动提示功能的菜单——AutoCompleteTextView与数组 (111)4.14 数字及模拟小时钟设计——AnalogClock与DigitalClock的原理 (113)4.15 动态输入日期与时间——DatePicker与TimePicker应用 (116)4.16 猜猜红心A在那儿——ImageView点击事件与透明度处理 (120)4.17 后台程序运行进度提示——ProgressBar与Handler的整合应用 (124)4.18 动态文字排版——GridView与ArrayAdapter设计 (129)4.19 在Activity里显示列表列表——ListView的布局 (133)4.20 以动态列表配置选项——ListActivity与Menu整合技巧 (136)4.21 查找程序根目录下所有文件——Java I/O与ListActivity的结合 (140)4.22 加载手机磁盘里的图文件——使用decodeFile方法 (144)4.23 动态放大缩小ImageView里的图片——运用Matrix对象来缩放图文件 (146)4.24 动态旋转图片——Bitmap与Matrix旋转ImageView (150)4.25 猜猜我在想什么——RadioButton ID (154)4.26 离开与关闭程序的弹出窗口——对话窗口上的ICON图标 (158)第5章交互式通信服务与手机控制...... 162 5.1 具有正则表达式的TextView——Linkify规则 (163)5.2 ACTION！CALL！拨打电话——Intent.ACTION.CALL的使用 (165)5.3 自制发送短信程序——SmsManager与PendingIntent对象 (168)5.4 自制发送Email程序——Intent在Email上的使用 (174)5.5 自制日历手机数据库——实现SQLiteOpenHelper. 1785.6 手机震动的节奏——Vibrator对象及周期运用 (184)5.7 图文可视化提醒——Toast与LinearLayout View (188)5.8 状态栏的图标与文字提醒——NotificationManager与Notification对象的应用 (190)5.9 搜索手机通讯录自动完成——使用ContentResolver. 1955.10 取得联系人资料——Provider.Contact的使用 (200)5.11 制作有图标的文件资源管理器——自定义Adapter对象 (204)5.12 还原手机默认桌面——重写clearWallpaper方法 (210)5.13 置换手机背景图——Gallery与setWallpaper整合实现 (213)5.14 撷取手机现存桌面——getWallpaper与setImageDrawable.. 2175.15 文件资源管理器再进化——Java I/O修改文件名及删除 (219)5.16 取得目前File与Cache的路径——getCacheDir与getFilesDir. 2285.17 打开/关闭WiFi服务——WifiManager状态判断 (232)5.18 取得SIM卡内的信息——TelephonyManager的应用 (242)5.19 调用拨号按钮——打电话CALL_BUTTON (247)5.20 DPAD按键处理——onKeyDown事件与Layout坐标交互 (249)5.21 任务管理器正在运行的程序——RunningTaskInfo (254)。

一、Introduction(入门)0、Introduction to Android(引进到Android)Android provides a rich application framework that allows you to build innovative apps and games for mobile devices in a Java language environment. The documents listed in the left navigation provide details about how to build apps using Android's various APIs.To learn how apps work, startwith App Fundamentals.To begin coding right away, read Building Your First AppAndroid提供了丰富的应用程序框架，它允许您在Java语言环境中构建移动设备的创新应用程序和游戏。

在左侧导航中列出的文档提供了有关如何使用Android的各种API来构建应用程序的详细信息。

要了解如何开发应用，从应用基础开始。

如何开始一个正确的编码，请参照建立你的第一个应用程序。

Apps provide multiple entry points 应用程序提供多个入口点Apps adapt to different devices 应用程序适应不同的设备Android apps are built as a combination of distinct components that can be invoked individually. For instance, an individual activity provides a single screen for a user interface, and a service independently performs work in the background.Android应用程序被构建为能够单独地被调用不同的部件的组合。

Android开发文档（二）一、Android Library (2)二、圆角 (4)三、适应屏幕的背景图 (6)四、改变图片的颜色 (7)五、仿iphone的点击效果 (8)六、有最大最小宽高值的ImageView (9)七、屏幕的某位置弹出缩放动画 (10)八、列表项的删除动画效果 (12)九、自定义padding动画 (14)十、Activity向右Touch退出 (16)十一、点击编辑框外任意点，隐藏软键盘 (20)十二、Activity的ContentView添加删除 (22)十三、Activity的WindowManager (25)吴健兴/2013.08.19一、Android LibraryLibrary工程的好处一些util 方法或者我们自定义的控件放到Library工程，实现复用；相比jar 包而言，他可以实现资源文件的复用甚至覆盖；模块化设计实现代码共享，便于管理，提高效率；Library工程的设置在包资源管理窗口，右键点击要进行设置的项目->属性->Android->勾选Is Libarary；Library工程的引用在包资源管理窗口，右键点击要引用Library工程的项目->属性->Android->右下Add ->选择要引用的Libarary->确定；二、圆角方式一：使用xml文件定义圆角方式二：canvas.drawBitmap()此方法需要new一个canvas来生成圆角；方式三：canvas.clipPath()此方法需要View中canvas对象来生成圆角，这个对象在draw类方法中被传入；所以要继承View并重写draw()，onDraw()，dispatchDraw()等方法进行实现；通过第三种方法的效果作用范围更广，使用更灵活：三、适应屏幕的背景图一张720*1280的图片占用的内存大概为：720*1280=921600B，接近1M，一张1M的图片存在于应用内存中，是一件很危险的事情，不仅会影响当前的页面的绘制性能，会占用了大量的内存，使得OutOfMemoryError错误出现的概率更高；所以对于大背景图，应当做一些降低消耗的处理；而当背景图很长，或者很宽时，我们应该对背景图进行截取，使得图片的宽高比与屏幕的宽高比一致，使得图片中的图案不至于被拉伸；所以，对于一张比较大的并且高宽比与屏幕的宽高比不一致的可以做以下的处理：1、缩小到和屏幕一样大；2、裁剪得和屏幕宽高比一样；四、改变图片的颜色下图动态条目的声音图标，原来是白色的，可以通过代码改变图标为红色。

Android Application FundamentalsAndroid applications are written in the Java programming language. The compiled Java code — along with any data and resource files required by the application — is bundled by the aapt tool into an Android package, an archive file marked by an .apk suffix. This file is the vehicle for distributing the application and installing it on mobile devices; it's the file users download to their devices. All the code in a single .apk file is considered to be one application.In many ways, each Android application lives in its own world:(1) By default, every application runs in its own Linux process. Android starts the process when any of the application's code needs to be executed, and shuts down the process when it's no longer needed and system resources are required by other applications.(2) Each process has its own virtual machine (VM), so application code runs in isolation from the code of all other applications.(3) By default, each application is assigned a unique Linux user ID. Permissions are set so that the application's files are visible only to that user and only to the application itself — although there are ways to export them to other applications as well.It's possible to arrange for two applications to share the same user ID, in which case they will be able to see each other's files. To conserve system resources, applications with the same ID can also arrange to run in the same Linux process, sharing the same VM..1 Application ComponentsA central feature of Android is that one application can make use of elements of other applications (provided those applications permit it). For example, if your application needs to display a scrolling list of images and another application has developed a suitable scroller and made it available to others, you can call upon that scroller to do the work, rather than develop your own. Your application doesn't incorporate the code ofthe other application or link to it. Rather, it simply starts up that piece of the other application when the need arises.For this to work, the system must be able to start an application process when any part of it is needed, and instantiate the Java objects for that part. Therefore, unlike applications on most other systems, Android applications don't have a single entry point for everything in the application (no main() function, for example). Rather, they have essential components that the system can instantiate and run as needed. There are four types of components:(1) ActivitiesAn activity presents a visual user interface for one focused endeavor the user can undertake. For example, an activity might present a list of menu items users can choose from or it might display photographs along with their captions. A text messaging application might have one activity that shows a list of contacts to send messages to, a second activity to write the message to the chosen contact, and other activities to review old messages or change settings. Though they work together to form a cohesive user interface, each activity is independent of the others. Each one is implemented as a subclass of the Activity base class.An application might consist of just one activity or, like the text messaging application just mentioned, it may contain several. What the activities are, and how many there are depends, of course, on the application and its design. Typically, one of the activities is marked as the first one that should be presented to the user when the application is launched. Moving from one activity to another is accomplished by having the current activity start the next one.Each activity is given a default window to draw in. Typically, the window fills the screen, but it might be smaller than the screen and float on top of other windows. An activity can also make use of additional windows — for example, a pop-up dialog that calls for a user response in the midst of the activity, or a window that presents users with vital information when they select a particular item on-screen.The visual content of the window is provided by a hierarchy of views — objectsderived from the base View class. Each view controls a particular rectangular space within the window. Parent views contain and organize the layout of their children. Leaf views (those at the bottom of the hierarchy) draw in the rectangles they control and respond to user actions directed at that space. Thus, views are where the activity's interaction with the user takes place.For example, a view might display a small image and initiate an action when the user taps that image. Android has a number of ready-made views that you can use — including buttons, text fields, scroll bars, menu items, check boxes, and more.A view hierarchy is placed within an activity's window by the Activity.setContentView() method. The content view is the View object at the root of the hierarchy. (See the separate User Interface document for more information on views and the hierarchy.)(2) ServicesA service doesn't have a visual user interface, but rather runs in the background for an indefinite period of time. For example, a service might play background music as the user attends to other matters, or it might fetch data over the network or calculate something and provide the result to activities that need it. Each service extends the Service base class.A prime example is a media player playing songs from a play list. The player application would probably have one or more activities that allow the user to choose songs and start playing them. However, the music playback itself would not be handled by an activity because users will expect the music to keep playing even after they leave the player and begin something different. To keep the music going, the media player activity could start a service to run in the background. The system would then keep the music playback service running even after the activity that started it leaves the screen.It's possible to connect to (bind to) an ongoing service (and start the service if it's not already running). While connected, you can communicate with the service through an interface that the service exposes. For the music service, this interface might allow users to pause, rewind, stop, and restart the playback.Like activities and the other components, services run in the main thread of the application process. So that they won't block other components or the user interface, they often spawn another thread for time-consuming tasks (like music playback). See Processes and Threads, later.(3) Broadcast receiversA broadcast receiver is a component that does nothing but receive and react to broadcast announcements. Many broadcasts originate in system code — for example, announcements that the timezone has changed, that the battery is low, that a picture has been taken, or that the user changed a language preference. Applications can also initiate broadcasts — for example, to let other applications know that some data has been downloaded to the device and is available for them to use.An application can have any number of broadcast receivers to respond to any announcements it considers important. All receivers extend the BroadcastReceiver base class.Broadcast receivers do not display a user interface. However, they may start an activity in response to the information they receive, or they may use the NotificationManager to alert the user. Notifications can get the user's attention in various ways — flashing the backlight, vibrating the device, playing a sound, and so on. They typically place a persistent icon in the status bar, which users can open to get the message.(4) Content providersA content provider makes a specific set of the application's data available to other applications. The data can be stored in the file system, in an SQLite database, or in any other manner that makes sense. The content provider extends the ContentProvider base class to implement a standard set of methods that enable other applications to retrieve and store data of the type it controls. However, applications do not call these methods directly. Rather they use a ContentResolver object and call its methods instead. A ContentResolver can talk to any content provider; it cooperates with the provider to manage any interprocess communication that's involved.See the separate Content Providers document for more information on using content providers.Whenever there's a request that should be handled by a particular component, Android makes sure that the application process of the component is running, starting it if necessary, and that an appropriate instance of the component is available, creating the instance if necessary.2 Activating components: intentsContent providers are activated when they're targeted by a request from a ContentResolver. The other three components — activities, services, and broadcast receivers — are activated by asynchronous messages called intents. An intent is an Intent object that holds the content of the message. For activities and services, it names the action being requested and specifies the URI of the data to act on, among other things. For example, it might convey a request for an activity to present an image to the user or let the user edit some text. For broadcast receivers, theIntent object names the action being announced. For example, it might announce to interested parties that the camera button has been pressed.There are separate methods for activating each type of component:(1). An activity is launched (or given something new to do) by passing an Intent object toContext.startActivity() or Activity.startActivityForResult(). The responding activity can look at the initial intent that caused it to be launched by calling its getIntent() method. Android calls the activity's onNewIntent() method to pass it any subsequent intents. One activity often starts the next one. If it expects a result back from the activity it's starting, it calls startActivityForResult() instead of startActivity(). For example, if it starts an activity that lets the user pick a photo, it might expect to be returned the chosen photo. The result is returned in an Intent object that's passed to the calling activity's onActivityResult() method.(2). A service is started (or new instructions are given to an ongoing service) bypassing an Intent object to Context.startService(). Android calls the service's onStart() method and passes it the Intent object. Similarly, an intent can be passed to Context.bindService() to establish an ongoing connection between the calling component and a target service. The service receives the Intent object in an onBind() call. (If the service is not already running, bindService() can optionally start it.) For example, an activity might establish a connection with the music playback service mentioned earlier so that it can provide the user with the means (a user interface) for controlling the playback. The activity would call bindService() to set up that connection, and then call methods defined by the service to affect the playback.A later section, Remote procedure calls, has more details about binding to a service.(3). An application can initiate a broadcast by passing an Intent object to methods like Context.sendBroadcast(),Context.sendOrderedBroadcast(),Context.sendStickyBroadcast () in any of their variations.Android delivers the intent to all interested broadcast receivers by calling their onReceive() methods. For more on intent messages, see the separate article, Intents and Intent Filters.3 Shutting down componentsA content provider is active only while it's responding to a request from a ContentResolver. And a broadcast receiver is active only while it's responding to a broadcast message. So there's no need to explicitly shut down these components.Activities, on the other hand, provide the user interface. They're in a long-running conversation with the user and may remain active, even when idle, as long as the conversation continues. Similarly, services may also remain running for a long time. So Android has methods to shut down activities and services in an orderly way:(1). An activity can be shut down by calling its finish() method. One activity can shut down another activity (one it started with startActivityForResult()) by calling finishActivity().(2). A service can be stopped by calling its stopSelf() method, or by callingContext.stopService().Components might also be shut down by the system when they are no longer being used or when Android must reclaim memory for more active components. A later section, Component Lifecycles, discusses this possibility and its ramifications in more detail.4 The manifest fileBefore Android can start an application component, it must learn that the component exists. Therefore, applications declare their components in a manifest file that's bundled into the Android package, the .apk file that also holds the application's code, files, and resources.The manifest is a structured XML file and is always named AndroidManifest.xml for all applications. It does a number of things in addition to declaring the application's components, such as naming any libraries the application needs to be linked against (besides the default Android library) and identifying any permissions the application expects to be granted.But the principal task of the manifest is to inform Android about the application's components.For example, an activity might be declared as follows:The name attribute of the <activity> element names the Activity subclass that implements the activity. The icon and label attributes point to resource files containing an icon and label that can be displayed to users to represent the activity.The other components are declared in a similar way — <service> elements for services, <receiver> elements for broadcast receivers, and <provider> elements for content providers. Activities, services, and content providers that are not declared in the manifest are not visible to the system and are consequently never run. However, broadcast receivers can either be declared in the manifest, or they can be created dynamically in code (as BroadcastReceiver objects) and registered with the system by calling Context.registerReceiver().For more on how to structure a manifest file for your application, see The Android Manifest.xml File.5 Intent filtersAn Intent object can explicitly name a target component. If it does, Android finds that component (based on the declarations in the manifest file) and activates it. But if a target is not explicitly named, Android must locate the best component to respond to the intent. It does so by comparing the Intent object to the intent filters of potential targets.A component's intent filters inform Android of the kinds of intents the component is able to handle. Like other essential information about the component, they're declared in the manifest file. Here's an extension of the previous example that adds two intent filters to the activity:The first filter in the example — the combination of the action "android.intent.action.MAIN" and the category"UNCHER" — is a common one. It marks the activity as one that should be represented in the application launcher, the screen listing applications users can launch on the device. In other words, the activity is the entry point for the application, the initial one users would see when they choose the application in the launcher.The second filter declares an action that the activity can perform on a particular type of data.A component can have any number of intent filters, each one declaring a different set of capabilities. If it doesn't have any filters, it can be activated only by intents that explicitly name the component as the target.For a broadcast receiver that's created and registered in code, the intent filter is instantiated directly as an IntentFilter object. All other filters are set up in the manifest.For more on intent filters, see a separate document, Intents and Intent Filters.6 XML-Based LayoutWhile it is technically possible to create and attach widgets to our activity purely through Java code, the way we did in Chapter 4, the more common approach is to use an XML-based layout file. Dynamic instantiation of widgets is reserved for more complicated scenarios, where the widgets are not known at compile-time (e g., populating a column of radio buttons based on data retrieved off the Internet).With that in mind, it’s time to break out the XML and learn how to lay out Android activities that way.As the name suggests, an XML-based layout is a specification of widgets’ relationships to each other—and to their containers (more on this in Chapter 7)—encoded in XML format. Specifically, Android considers XML-based layouts to be resources, and as such layout files are stored in the res/layout directory inside your Android project.Each XML file contains a tree of elements specifying a layout of widgets and their containers that make up one view hierarchy. The attributes of the XML elements are properties, describing how a widget should look or how a container should behave. For example, if a Button element has an attribute value of android:textStyle = "bold", that means that the text appearing on the face of the button should be rendered in a boldface font style.Android’s SDK ships with a tool (aapt) which uses the layouts. This tool should be automatically invoked by your Android tool chain (e.g., Eclipse, Ant’s build.xml). Of particular importance to you as a developer is that aapt generates the R.java source file within your project, allowing you to access layouts and widgets within those layouts directly from your Java code.XML as a GUI definition format is becoming more commonplace. Microsoft’s XAML2, Adobe’s Flex3, and Mozilla’s XUL4 all take a similar approach to that of Android: put layout details in an XML file and put programming smarts in source files (e.g., JavaScript for XUL). Many less-well-known GUI frameworks, such as ZK5, alsouse XML for view definition. While “following the herd” is not necessarily the best policy, it does have the advantage of helping to ease the transition into Android from any other XML-centered view description language.Android应用基础Android应用程序使用Java编程语言开发。

android 文档(android官方文档中文版)android官方文档中文版香港中文大学（深圳）要求的文件有中文吗？您还可以在这里在百度图书馆中搜索中文文档。

确切地说，没有正式的中文文档，英文很好，只要您有英语文档，它就可以在您的机器上使用。

好了，下一个金山词霸，正确地在开发过程中如何获取中文帮助文件使用浏览器打开帮助文件，浏览器顶部会出现一个提示，询问您是否要翻译它。

您选择简体中文。

首先，中文帮助文档很少。

有一个非政府组织翻译。

这很棒。

你可以找到它。

其次，如果您处于脱机状态，则可以在更新帮助文档时对其进行更新，该帮助文档将成为本地文档。

希望它能对您有所帮助。

我还没有做过，农民伯父的翻译还没有完成。

我建议您使用翻译工具并慢慢观看。

您还可以提高英语水平。

嘿~~可以给我发中文｀！〜电子邮件非常感谢您选择培训机构。

至少，有必要了解一些条件，例如教师是否真的做到了这种发展？它是线上的真实应用程序吗？教学设备怎么样？您就业后是否付款？我所知道的最好的是华夏博大学学院。

基本情况很好。

你可以找到答案！学习书籍是什么？就我个人而言，我觉得无论我推荐多少本书，都不如有一位导师来理解和学习。

但是，学习时会遇到很多纠缠的问题，但也有很多人选择在课堂上进行系统地学习，基础教程，第一行代码和其他基础知识都还可以，但您也可以在前锋找到一些外部教程，下载并查看或可以上网看看，其中一些还不错。

疯狂的讲义Lao Luo是一本Android 视频学习手册。

学习手册包含一章，一个示例，并且源代码文档可自由查看。

这些示例是交互式且可运行的。

源代码使用目录结构，突出显示代码，并在文档结构图中显示文档。

，您可以快速找到。

移动助手中的下载图标上有一个外壳。

在这里，我将分享您收集的一些开发书籍：书籍的正式文件，简介和正式文件，其中简要介绍了所有方面，值得阅读。

下载：该手册是每个开发人员都必须阅读的内容。

它的使用和功能，再加上它，肯定会获得更多。

Android开发指南Android中文开发文档-初学者目录应用程序基础Application Fundamentals (4)关键类 (4)应用程序组件 (5)激活组件：intent (7)关闭组件 (7)manifest文件 (8)Intent过滤器 (9)Activity和任务 (10)Affinity（吸引力）和新任务 (11)加载模式 (12)清理堆栈 (13)启动任务 (14)进程和线程 (14)进程 (14)线程 (15)远程过程调用 (15)线程安全方法 (16)组件生命周期 (17)Activity生命周期 (17)调用父类 (17)服务生命周期 (20)广播接收器生命周期 (22)用户界面User Interface (23)视图层次View Hierarchy (24)布局Layout (24)部件Widgets (25)用户界面事件UI Events (26)菜单Menus (26)高级话题Advanced Topics (27)适配器Adapter (27)风格与主题Styles and Themes (27)资源和资产Resources and Assets (27)资源引用Resource Reference (43)国际化和本地化Internationalization and Localization (43)意图和意图过滤器Intents and Intent Filters (43)意图过滤器Intent filters (47)通常情况Common cases (51)使用意图匹配Using intent matching (52)数据存储Data Storage (52)概览Storage quickview (52)✧系统偏好：快速，轻量级存储 (52)✧文件：存储到设备内部或可移动闪存 (52)✧数据库：任意的结构化存储 (52)✧支持基于网络的存储 (52)系统偏好Preferences (53)文件Files (54)网络Network (55)内容提供器Content Providers (55)内容提供器的基础知识Content Provider Basics (55)查询一个内容提供器Querying a Content Provider (57)修改数据Modifying Data (61)创建一个内容提供器Creating a Content Provider (64)Content URI 总结 (67)清单文件The AndroidManifest.xml File (68)清单文件结构Structure of the Manifest File (68)文件约定File Conventions (70)文件特性File Features (73)应用程序基础Application Fundamentals关键类1.Activity2.Service3.BroadcastReceiver4.ContentProvider5.IntentAndroid应用程序使用Java做为开发语言。

android 中文文档∙丰富而又可扩展的视图（Views），可以用来构建应用程序，它包括列表（lists），网格（grids），文本框（text boxes），按钮（buttons），甚至可嵌入的web浏览器。

∙内容提供器（Content Providers）使得应用程序可以访问另一个应用程序的数据（如联系人数据库），或者共享它们自己的数据∙资源管理器（Resource Manager）提供非代码资源的访问，如本地字符串，图形，和布局文件（layout files ）。

∙通知管理器（Notification Manager）使得应用程序可以在状态栏中显示自定义的提示信息。

∙活动管理器（Activity Manager）用来管理应用程序生命周期并提供常用的导航回退功能。

有关更多的细节和怎样从头写一个应用程序，请参考如何编写一个Android 应用程序.Android 包含一些C/C++库，这些库能被Android系统中不同的组件使用。

它们通过Android 应用程序框架为开发者提供服务。

以下是一些核心库：∙系统C 库- 一个从BSD 继承来的标准C 系统函数库（libc ），它是专门为基于embedded linux 的设备定制的。

∙媒体库- 基于PacketVideo OpenCORE；该库支持多种常用的音频、视频格式回放和录制，同时支持静态图像文件。

编码格式包括MPEG4,H.264, MP3, AAC, AMR, JPG, PNG 。

∙Surface Manager - 对显示子系统的管理，并且为多个应用程序提供了2D和3D图层的无缝融合。

∙LibWebCore - 一个最新的web浏览器引擎用，支持Android浏览器和一个可嵌入的web视图。

∙SGL - 底层的2D图形引擎∙3D libraries - 基于OpenGL ES 1.0 APIs实现；该库可以使用硬件3D 加速（如果可用）或者使用高度优化的3D软加速。