Building a Custom Preference The Android framework includes a variety of Preference subclasses that allow you to build a UI for several different types of settings. However, you might discover a setting you need for which there’s no built-in solution…

一般来说,我们的APP都会有自己的设置页面,那么其实我们有非常简单的制作方法.老样子,先看效果图. 然后就是看源代码了. 第一步,先在res文件夹中新建一个xml文件夹,用来存放preferences.xml文件 <?xml version="1.0" encoding="utf-8"?> <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android…

1.Defining Preferences in XML Although you can instantiate new Preference objects at runtime, you should define your list of settings in XML with a hierarchy of Preference objects. Using an XML file to define your collection of settings is preferred…

1.Overview Instead of using View objects to build the user interface, settings are built using various subclasses of thePreference class that you declare in an XML file. A Preference object is the building block for a single setting. Each Preference …

Reading Preferences By default, all your app's preferences are saved to a file that's accessible from anywhere within your application by calling the static method PreferenceManager.getDefaultSharedPreferences(). This returns theSharedPreferences obj…

1.Using Preference Headers In rare cases, you might want to design your settings such that the first screen displays only a list of subscreens(such as in the system Settings app, as shown in figures 4 and 5). When you're developing such a design for…

Setting Default Values The preferences you create probably define some important behaviors for your application, so it's necessary that you initialize the associated SharedPreferences file with default values for each Preference when the user first o…

Creating a Preference Activity To display your settings in an activity, extend the PreferenceActivity class. This is an extension of the traditional Activity class that displays a list of settings based on a hierarchy of Preference objects. ThePrefer…

前篇文章Android ApiDemo示例解析(31):App->Preferences->Launching preferences 中用到了Advanced preferences 中定义的AdvancedPreferences. 本篇具体介绍AdvancedPreferences, 这个例子称为Advanced ,是因为它涉及到了自定义Preference, 并在一个工作线程中刷新某个Preference的值. Preference 为显示在PreferenceActivity (一般以…

在某些情况下,将读请求发送给副本集的备份节点是合理的,例如,单个服务器无法处理应用的读压力,就可以把查询请求路由到可复制集中的多台服务器上.现在绝大部分MongoDB驱动支持读偏好设置(read preference:或翻译为读取首选项),用来告诉驱动从特定的节点读取数据. 1.副本集读偏好 primary — 这是默认的设置,表明只从可复制集的主节点读取数据,因此具有强一致性.如果可复制集有问题,并且没有可选举的从节点,就表示出现错误. premaryPreferred — 设置了此参数的驱动…