Android Lint简介（转载）

当然Android Lint远远不至检查以上的错误，更多的内容请参考《Android Lint 检查规则列表》

如果你只是想对lint的检查规则做些简单的定制，请参考《Android Lint 检查规则的定制（基本篇）》或英文官方文档

If you have the SDK tools/ directory on your path, you can invoke it as “lint”. Just point to a specific Android project directory. You can also point to a random directory, which (if it is not an Android project) will be searched recursively and all projects under that directory will be checked. (And you can also specify multiple projects separated by spaces)

在Android SDK的tools下有个叫lint.bat的文件，它就是lint的命令行工具。

lint命令后可以带一个或多个参数，参数之间用空格隔开，参数表示的是需要使用lint进行扫描的Android项目的目录。

linux命令行

$ lint --disable MissingTranslation,UnusedIds,Usability:Icons/src/astrid/

lint的有些检查项默认是关闭的(disable),在执行lint命令时可以通过--enable选项开启它。-enable选项后接要开启的检查规则项的id（比如示例5中的MissingTranslation ）或检查规则项的类别（示例5中的Usability:Icons）

$ lint --disable MissingTranslation,UnusedIds,Usability:Icons/src/astrid/

可以通过lint的--list选项来得到检查项类别和检查项id.

比如：

$ lint --list
Valid issue categories:
Correctness
Security
Performance
Usability
Usability:Icons
Accessibility
Internationalization

Valid issue id‘s:
"ContentDescription": Ensures that image widgets provide a contentDescription
"DuplicateIds": Checks for duplicate ids within a single layout
"StateListReachable": Looks for unreachable states in a <selector>
"InefficientWeight": Looks for inefficient weight declarations in LinearLayouts
"ScrollViewSize": Checks that ScrollViews use wrap_content in scrolling dimension
"MergeRootFrame": Checks whether a root <FrameLayout> can be replaced with a <merge> tag
...

$ lint --show MissingPrefix
MissingPrefix
-------------
Summary: Detect XML attributes not using the Android namespace

Priority: 8 / 10
Severity: Warning
Category: Correctness

Most Android views have attributes in the Android namespace. When
referencing these attributes you *must* include the namespace prefix,
or your attribute will be interpreted by aapt as just a custom
attribute.

html输出报告如图2所示

 

By default, links to source files will just use local file:// path resources. You can remap the URLs to a different prefix with the --url option. For example:

在lint中，你可以使用--help选项来得到lint命令的一些帮助信息。

• Automatic fixes for many warnings自动修正大量警告
• Lint gets run automatically on various editing operations当编辑操作完成后，立即自动运行
• Ability to suppress types of errors as well as specific instances of an error可以suppress(忽略)一种类型的erro，也可以suppress(忽略)特定的一个erro
• Ability to configure issue severities能够配置issue（问题）的severities(严重性)
• Jump directly to the problem source from the lint view通过lint视图能直接跳转到其问题对应的源码处

Lint将在以下情况下自动运行：

• Export an APK. In this case it runs lint in a special mode which only looks for fatal errors (which is faster) and aborts the export if any fatal errors are found. You can turn off this in the Lint Options.在导出APK文件的时候，lint会做快速的扫描，以寻找fatal的错误。如果发现有fatal的错误，导出APK的操作将被迫终止
• Edit and Save and XML file, such as a layout file or a manifest file. In this case, all the file-scope checks that apply to the given file are run and editor markers are added for any issues found.编辑和保存XML文件，lint也会自动扫描这些文件。另外从ADT20开始，对于java源码文件在编辑和保存后，lint也会对他们进行 扫描。
• Use the layout editor. After every UI operation, file-scope checks (such as the various layoutopt rules) are run on the layout file and the results are shown in a special lint window (which can be opened from the error marker which shows in the top right corner of the layout editor when errors are found).对于使用layout editor来操作布局文件时，在每个UI操作后,lint也会自动扫描该布局文件。

在Eclipse中，你可以通过两种方式来手动进行lint的扫描：

一种方式是通过工具栏，双击图3-1中红色箭头指向的按钮，然后出现图3-2所示的下拉框，在该下拉选择要进行lint扫描的工程

 

 

 

运行lint之后，你将看到如图3-4或图3-5所示的lint 窗口

 

 

默认情况下，同一个类型的issue都是折叠成一块的，图3-4和图3-5是我手动展开的。

lint窗口的工具栏上有一些按钮，如图3-6所示

它们的意义分别如下

•  Refresh, which re-runs the current analysis on the same projects
•  Fix, which automatically fixes the issue (this applies to issues where a quickfix is available)
•  Suppress this issue with an attribute or annotation
•  Ignore in this file (saves suppress information in lint.xml)
•  Ignore in this project (ditto)
•  Always ignore
•  Delete this lint marker
•  Delete all lint markers
•  Expand All, 
   Collapse All
•   Configure Columns用于设置在lint Window中对于检查出的issue的哪些项显示哪些项不显示，如图3-7所示
   
•  Edit Options Edit Options 点击该按钮会弹出Lint Preference dialog，如图1或图3-8在里面你可以定制默认/全局的Android Lint的基本检查规则，在其中可以设置所有项目默认的lint检查规则的检查级别，把检查级别(Severity)设为”ignore“,其实就是忽略（suppress）该检查规则

  The Edit Options actions brings up the Lint Preference dialog, which has also been improved.  You can now search through the options by filter:

点击Edit Options按钮会弹出处理Lint Preference dialog，在里面可以定制默认/全局的Android Lint的基本检查规则

 3.3、Quick Fixes

Many lint warnings have automatic fixes. For example, the various layoutopt fixes suggest replacements (e.g. replace wrap_content with 0dp). 

• From the lint view（如图3-6所示）, click the lightbulb 
    to invoke a fix.
• From the layout editor warning summary, click the Fix button to fix.
• And from the XML source editor, invoke the Quick Fix (Ctrl-1 or Command-1) and pick the quick fix associated with the warning.

• Ignore the warning in this file only
• Ignore the warning in this project
• Ignore the warning, period.
• Ignore warnings using annotations or attributes, as explained here.

 

(If you do not see the lint fix action in the quickfix list, see the Known Bugs section)

These choices are stored in a file named lint.xml in the project, which is also read by the command line tool. Thus, you can ignore warnings from the UI, and check in thelint.xml file with your source projects, and others running lint will not see warnings you have ignored (presumably because they have been manually verified).

你的选择在被存在Android工程目录下的 lint.xml 文件中

关于此的详细内容请参考《Android Lint 检查规则的定制（基本篇）》