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if("0".equals(groupResponseList.get(position).getType()))防止空指针将已知对象放在前面，这样有助于规避空指针

This page defines more types of resources you can externalize, including:BoolXML resource that carries a boolean value.ColorXML resource that carries a color value (a hexadecimal color).DimensionX

A style resource defines the format and look for a UI. A style can be applied to an individual View (from within a layout file) or to an entire Activity or application (from within the manifest fi

A string resource provides text strings for your application with optional text styling and formatting. There are three types of resources that can provide your application with strings:StringXML

A menu resource defines an application menu (Options Menu, Context Menu, or submenu) that can be inflated withMenuInflater.For a guide to using menus, see the Menus developer guide.FILE LOCATION:r

A layout resource defines the architecture for the UI in an Activity or a component of a UI.FILE LOCATION:res/layout/filename.xmlThe filename will be used as the resource ID.COMPILED RESOURCE DATA

A drawable resource is a general concept for a graphic that can be drawn to the screen and which you can retrieve with APIs such as getDrawable(int) or apply to another XML resource with attributes

A ColorStateList is an object you can define in XML that you can apply as a color, but will actually change colors, depending on the state of the View object to which it is applied. For example, a

An animation resource can define one of two types of animations:Property AnimationCreates an animation by modifying an object's property values over a set period of time with an Animator.View Anim

Every application must have an AndroidManifest.xml file (with precisely that name) in its root directory. The manifest file presents essential information about your app to the Android system, infor

SYNTAX: android:name="string" />CONTAINED IN:DESCRIPTION:Adds an action to an intent filter. An  element must contain one or more elements. If it doesn't contain any, no Intent obj

SYNTAX: android:allowEmbedded=["true" | "false"]          android:allowTaskReparenting=["true" | "false"]          android:alwaysRetainTaskState=["true" | "false"]          android:autoRemoveFrom

SYNTAX: android:icon="drawable resource"               android:label="string resource"               android:priority="integer" >    . . .CONTAINED IN:   MUST CONTAIN:CAN CONTAIN: DESC

SYNTAX: android:functionalTest=["true" | "false"]                 android:handleProfiling=["true" | "false"]                 android:icon="drawable resource"                 android:label="string

SYNTAX: android:scheme="string"      android:host="string"      android:port="string"      android:path="string"      android:pathPattern="string"      android:pathPrefix="string"      android

SYNTAX: android:path="string"                      android:pathPattern="string"                      android:pathPrefix="string" />CONTAINED IN:DESCRIPTION:Specifies which data subsets o

SYNTAX:compatible-screens>    screen android:screenSize=["small" | "normal" | "large" | "xlarge"]            android:screenDensity=["ldpi" | "mdpi" | "hdpi" | "xhdpi"                             

SYNTAX: android:name="string" />CONTAINED IN:DESCRIPTION:Adds a category name to an intent filter. See Intents and Intent Filters for details on intent filters and the role of category s

SYNTAX: android:allowTaskReparenting=["true" | "false"]             android:allowBackup=["true" | "false"]             android:backupAgent="string"             android:banner="drawable resource"

SYNTAX: android:enabled=["true" | "false"]                android:exported=["true" | "false"]                android:icon="drawable resource"                android:label="string resource"     

Each of the documents in this section describe the usage, format and syntax for a certain type of application resource that you can provide in your resources directory (res/).Here's a brief summar

Some device configurations can change during runtime (such as screen orientation, keyboard availability, and language). When such a change occurs, Android restarts the running Activity (onDestroy() is

Once you provide a resource in your application (discussed in Providing Resources), you can apply it by referencing its resource ID. All resource IDs are defined in your project's Rclass, which the 

AIDL (Android Interface Definition Language) is similar to other IDLs you might have worked with. It allows you to define the programming interface that both the client and service agree upon in order

A Service is an application component that can perform long-running operations in the background and does not provide a user interface. Another application component can start a service and it will

A Fragment represents a behavior or a portion of user interface in an Activity. You can combine multiple fragments in a single activity to build a multi-pane UI and reuse a fragment in multiple acti

An Activity is an application component that provides a screen with which users can interact in order to do something, such as dial the phone, take a photo, send an email, or view a map. Each activi

An intent allows you to start an activity in another app by describing a simple action you'd like to perform (such as "view a map" or "take a picture") in an Intent object. This type of intent is ca

An Intent is a messaging object you can use to request an action from another app component. Although intents facilitate communication between components in several ways, there are three fundamental

System PermissionsIn this documentSecurity ArchitectureApplication SigningUser IDs and File AccessUsing PermissionsNormal and Dangerous PermissionsPermission GroupsDefining and

Device CompatibilityAndroid is designed to run on many different types of devices, from phones to tablets and televisions. As a developer, the range of devices provides a huge potential audience

Content providers manage access to a structured set of data. They encapsulate the data, and provide mechanisms for defining data security. Content providers are the standard interface that connects da

A content provider manages access to a central repository of data. A provider is part of an Android application, which often provides its own UI for working with the data. However, content providers a

A content provider manages access to a central repository of data. You implement a provider as one or more classes in an Android application, along with elements in the manifest file. One of your clas

You should always externalize application resources such as images and strings from your code, so that you can maintain them independently. You should also provide alternative resources for specific d

It takes more than just code to build a great app. Resources are the additional files and static content that your code uses, such as bitmaps, layout definitions, user interface strings, animation ins

When an application component starts and the application does not have any other components running, the Android system starts a new Linux process for the application with a single thread of execution

The Android Home screen available on most Android devices allows the user to embed app widgets for quick access to content. If you're building a Home replacement or a similar app, you can also allow

App Widgets are miniature application views that can be embedded in other applications (such as the Home screen) and receive periodic updates. These views are referred to as Widgets in the user interf

Android 4.4 (API level 19) introduces the Storage Access Framework (SAF). The SAF makes it simple for users to browse and open documents, images, and other files across all of their their preferred do