Issue Types

## Overview

| Correctness
1 | error GradleCompatible: Incompatible Gradle Versions
1 | warning OldTargetApi: Target SDK attribute is not targeting latest version
1 | warning GradleDependency: Obsolete Gradle Dependency
1 | warning GradleDynamicVersion: Gradle Dynamic Version
| Performance
1 | warning UnusedResources: Unused resources
| Disabled Checks (21)

## Incompatible Gradle Versions

../../build.gradle:29: This support library should not use a different version (23) than the `compileSdkVersion` (26)

     26
     27 dependencies {
     28     compile fileTree(include: ['*.jar'], dir: 'libs')
     29     compile 'com.android.support:appcompat-v7:23.0.1'
     30     testCompile 'junit:junit:4.12'
     31     androidTestCompile('com.android.support.test.espresso:espresso-core:3.0.2', {
     32         exclude group: 'com.android.support', module: 'support-annotations'

There are some combinations of libraries, or tools and libraries, that are incompatible, or can lead to bugs. One such incompatibility is compiling with a version of the Android support libraries that is not the latest version (or in particular, a version lower than your `targetSdkVersion`.)
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "GradleCompatible" as explained in the Suppressing Warnings and Errors section.
GradleCompatible Correctness Error Priority 8/10

## Target SDK attribute is not targeting latest version

../../build.gradle:10: Not targeting the latest versions of Android; compatibility modes apply. Consider testing and updating this version. Consult the android.os.Build.VERSION_CODES javadoc for details.

      7
      8     defaultConfig {
      9         minSdkVersion 16
     10         targetSdkVersion 26
     11         versionCode 1
     12         versionName "1.0"

When your application runs on a version of Android that is more recent than your `targetSdkVersion` specifies that it has been tested with, various compatibility modes kick in. This ensures that your application continues to work, but it may look out of place. For example, if the `targetSdkVersion` is less than 14, your app may get an option button in the UI.
To fix this issue, set the `targetSdkVersion` to the highest available value. Then test your app to make sure everything works correctly. You may want to consult the compatibility notes to see what changes apply to each version you are adding support for: http://developer.android.com/reference/android/os/Build.VERSION_CODES.html
More info: http://developer.android.com/reference/android/os/Build.VERSION_CODES.html
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "OldTargetApi" as explained in the Suppressing Warnings and Errors section.
OldTargetApi Correctness Warning Priority 6/10

## Obsolete Gradle Dependency

../../build.gradle:29: A newer version of com.android.support:appcompat-v7 than 23.0.1 is available: 25.3.1

     26
     27 dependencies {
     28     compile fileTree(include: ['*.jar'], dir: 'libs')
     29     compile 'com.android.support:appcompat-v7:23.0.1'
     30     testCompile 'junit:junit:4.12'
     31     androidTestCompile('com.android.support.test.espresso:espresso-core:3.0.2', {
     32         exclude group: 'com.android.support', module: 'support-annotations'

This detector looks for usages of libraries where the version you are using is not the current stable release. Using older versions is fine, and there are cases where you deliberately want to stick with an older version. However, you may simply not be aware that a more recent version is available, and that is what this lint check helps find.
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "GradleDependency" as explained in the Suppressing Warnings and Errors section.
GradleDependency Correctness Warning Priority 4/10

## Gradle Dynamic Version

../../build.gradle:34: Avoid using + in version numbers; can lead to unpredictable and unrepeatable builds (com.facebook.react:react-native:+)

     31     androidTestCompile('com.android.support.test.espresso:espresso-core:3.0.2', {
     32         exclude group: 'com.android.support', module: 'support-annotations'
     33     })
     34     compile 'com.facebook.react:react-native:+'
     35 }

Using `+` in dependencies lets you automatically pick up the latest available version rather than a specific, named version. However, this is not recommended; your builds are not repeatable; you may have tested with a slightly different version than what the build server used. (Using a dynamic version as the major version number is more problematic than using it in the minor version position.)
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "GradleDynamicVersion" as explained in the Suppressing Warnings and Errors section.
GradleDynamicVersion Correctness Warning Priority 4/10

## Unused resources

../../src/main/res/values/strings.xml:2: The resource `R.string.app_name` appears to be unused

     1 <resources>
     2     <string name="app_name">testModule</string>
     3 </resources>

Unused resources make applications larger and slow down builds.
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "UnusedResources" as explained in the Suppressing Warnings and Errors section.
UnusedResources Performance Warning Priority 3/10

## Disabled Checks

One or more issues were not run by lint, either because the check is not enabled by default, or because it was disabled with a command line flag or via one or more `lint.xml` configuration files in the project directories.
AppLinksAutoVerifyError
Disabled By: Default
Ensures that app links are correctly set and associated with website.
More info: https://g.co/appindexing/applinks
To suppress this error, use the issue id "AppLinksAutoVerifyError" as explained in the Suppressing Warnings and Errors section.
AppLinksAutoVerifyWarning
Disabled By: Default
Ensures that app links are correctly set and associated with website.
More info: https://g.co/appindexing/applinks
To suppress this error, use the issue id "AppLinksAutoVerifyWarning" as explained in the Suppressing Warnings and Errors section.
BackButton
Disabled By: Default
According to the Android Design Guide,
"Other platforms use an explicit back button with label to allow the user to navigate up the application's hierarchy. Instead, Android uses the main action bar's app icon for hierarchical navigation and the navigation bar's back button for temporal navigation."
This check is not very sophisticated (it just looks for buttons with the label "Back"), so it is disabled by default to not trigger on common scenarios like pairs of Back/Next buttons to paginate through screens.
More info: http://developer.android.com/design/patterns/pure-android.html
To suppress this error, use the issue id "BackButton" as explained in the Suppressing Warnings and Errors section.
ConvertToWebp
Disabled By: Default
The WebP format is typically more compact than PNG and JPEG. As of Android 4.2.1 it supports transparency and lossless conversion as well. Note that there is a quickfix in the IDE which lets you perform conversion.
Launcher icons must be in the PNG format.
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "ConvertToWebp" as explained in the Suppressing Warnings and Errors section.
EasterEgg
Disabled By: Default
An "easter egg" is code deliberately hidden in the code, both from potential users and even from other developers. This lint check looks for code which looks like it may be hidden from sight.
To suppress this error, use the issue id "EasterEgg" as explained in the Suppressing Warnings and Errors section.
FieldGetter
Disabled By: Default
Accessing a field within the class that defines a getter for that field is at least 3 times faster than calling the getter. For simple getters that do nothing other than return the field, you might want to just reference the local field directly instead.
NOTE: As of Android 2.3 (Gingerbread), this optimization is performed automatically by Dalvik, so there is no need to change your code; this is only relevant if you are targeting older versions of Android.
More info: http://developer.android.com/guide/practices/design/performance.html#internal_get_set
To suppress this error, use the issue id "FieldGetter" as explained in the Suppressing Warnings and Errors section.
GoogleAppIndexingApiWarning
Disabled By: Default
Adds URLs to get your app into the Google index, to get installs and traffic to your app from Google Search.
More info: https://g.co/AppIndexing/AndroidStudio
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "GoogleAppIndexingApiWarning" as explained in the Suppressing Warnings and Errors section.
IconExpectedSize
Disabled By: Default
There are predefined sizes (for each density) for launcher icons. You should follow these conventions to make sure your icons fit in with the overall look of the platform.
More info: http://developer.android.com/design/style/iconography.html
To suppress this error, use the issue id "IconExpectedSize" as explained in the Suppressing Warnings and Errors section.
LogConditional
Disabled By: Default
The BuildConfig class (available in Tools 17) provides a constant, "DEBUG", which indicates whether the code is being built in release mode or in debug mode. In release mode, you typically want to strip out all the logging calls. Since the compiler will automatically remove all code which is inside a "if (false)" check, surrounding your logging calls with a check for BuildConfig.DEBUG is a good idea.
If you really intend for the logging to be present in release mode, you can suppress this warning with a @SuppressLint annotation for the intentional logging calls.
To suppress this error, use the issue id "LogConditional" as explained in the Suppressing Warnings and Errors section.
MangledCRLF
Disabled By: Default
On Windows, line endings are typically recorded as carriage return plus newline: \r\n.
This detector looks for invalid line endings with repeated carriage return characters (without newlines). Previous versions of the ADT plugin could accidentally introduce these into the file, and when editing the file, the editor could produce confusing visual artifacts.
More info: https://bugs.eclipse.org/bugs/show_bug.cgi?id=375421
To suppress this error, use the issue id "MangledCRLF" as explained in the Suppressing Warnings and Errors section.
MissingRegistered
Disabled By: Default
If a class is referenced in the manifest or in a layout file, it must also exist in the project (or in one of the libraries included by the project. This check helps uncover typos in registration names, or attempts to rename or move classes without updating the manifest file properly.
More info: http://developer.android.com/guide/topics/manifest/manifest-intro.html
To suppress this error, use the issue id "MissingRegistered" as explained in the Suppressing Warnings and Errors section.
NegativeMargin
Disabled By: Default
Margin values should be positive. Negative values are generally a sign that you are making assumptions about views surrounding the current one, or may be tempted to turn off child clipping to allow a view to escape its parent. Turning off child clipping to do this not only leads to poor graphical performance, it also results in wrong touch event handling since touch events are based strictly on a chain of parent-rect hit tests. Finally, making assumptions about the size of strings can lead to localization problems.
To suppress this error, use the issue id "NegativeMargin" as explained in the Suppressing Warnings and Errors section.
NewerVersionAvailable
Disabled By: Default
This detector checks with a central repository to see if there are newer versions available for the dependencies used by this project. This is similar to the `GradleDependency` check, which checks for newer versions available in the Android SDK tools and libraries, but this works with any MavenCentral dependency, and connects to the library every time, which makes it more flexible but also much slower.
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "NewerVersionAvailable" as explained in the Suppressing Warnings and Errors section.
PermissionImpliesUnsupportedChromeOsHardware
Disabled By: Default
The `<uses-permission>` element should not require a permission that implies an unsupported Chrome OS hardware feature. Google Play assumes that certain hardware related permissions indicate that the underlying hardware features are required by default. To fix the issue, consider declaring the corresponding uses-feature element with `required="false"` attribute.
More info: https://developer.android.com/topic/arc/manifest.html#implied-features
To suppress this error, use the issue id "PermissionImpliesUnsupportedChromeOsHardware" as explained in the Suppressing Warnings and Errors section.
Registered
Disabled By: Default
Activities, services and content providers should be registered in the `AndroidManifest.xml` file using `<activity>`, `<service>` and `<provider>` tags.
If your activity is simply a parent class intended to be subclassed by other "real" activities, make it an abstract class.
More info: http://developer.android.com/guide/topics/manifest/manifest-intro.html
To suppress this error, use the issue id "Registered" as explained in the Suppressing Warnings and Errors section.
SelectableText
Disabled By: Default
If a `<TextView>` is used to display data, the user might want to copy that data and paste it elsewhere. To allow this, the `<TextView>` should specify `android:textIsSelectable="true"`.
This lint check looks for TextViews which are likely to be displaying data: views whose text is set dynamically. This value will be ignored on platforms older than API 11, so it is okay to set it regardless of your `minSdkVersion`.
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "SelectableText" as explained in the Suppressing Warnings and Errors section.
StopShip
Disabled By: Default
Using the comment `// STOPSHIP` can be used to flag code that is incomplete but checked in. This comment marker can be used to indicate that the code should not be shipped until the issue is addressed, and lint will look for these.
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "StopShip" as explained in the Suppressing Warnings and Errors section.
TypographyQuotes
Disabled By: Default
Straight single quotes and double quotes, when used as a pair, can be replaced by "curvy quotes" (or directional quotes). This can make the text more readable.
Note that you should never use grave accents and apostrophes to quote, `like this'.
(Also note that you should not use curvy quotes for code fragments.)
More info: http://en.wikipedia.org/wiki/Quotation_mark
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "TypographyQuotes" as explained in the Suppressing Warnings and Errors section.
UnpackedNativeCode
Disabled By: Default
This app loads native libraries using `System.loadLibrary()`.
Consider adding `android:extractNativeLibs="false"` to the `<application>` tag in AndroidManifest.xml. Starting with Android 6.0, this will make installation faster, the app will take up less space on the device and updates will have smaller download sizes.
To suppress this error, use the issue id "UnpackedNativeCode" as explained in the Suppressing Warnings and Errors section.
UnsupportedChromeOsHardware
Disabled By: Default
The `<uses-feature>` element should not require this unsupported Chrome OS hardware feature. Any uses-feature not explicitly marked with `required="false"` is necessary on the device to be installed on. Ensure that any features that might prevent it from being installed on a Chrome OS device are reviewed and marked as not required in the manifest.
More info: https://developer.android.com/topic/arc/manifest.html#incompat-entries
To suppress this error, use the issue id "UnsupportedChromeOsHardware" as explained in the Suppressing Warnings and Errors section.
UnusedIds
Disabled By: Default
This resource id definition appears not to be needed since it is not referenced from anywhere. Having id definitions, even if unused, is not necessarily a bad idea since they make working on layouts and menus easier, so there is not a strong reason to delete these.
Note: This issue has an associated quickfix operation in Android Studio and IntelliJ IDEA.
To suppress this error, use the issue id "UnusedIds" as explained in the Suppressing Warnings and Errors section.

## Suppressing Warnings and Errors

Lint errors can be suppressed in a variety of ways:
1. With a `@SuppressLint` annotation in the Java code
2. With a `tools:ignore` attribute in the XML file
3. With a //noinspection comment in the source code
4. With ignore flags specified in the `build.gradle` file, as explained below
5. With a `lint.xml` configuration file in the project
6. With a `lint.xml` configuration file passed to lint via the --config flag
7. With the --ignore flag passed to lint.
To suppress a lint warning with an annotation, add a `@SuppressLint("id")` annotation on the class, method or variable declaration closest to the warning instance you want to disable. The id can be one or more issue id's, such as `"UnusedResources"` or `{"UnusedResources","UnusedIds"}`, or it can be `"all"` to suppress all lint warnings in the given scope.
To suppress a lint warning with a comment, add a `//noinspection id` comment on the line before the statement with the error.
To suppress a lint warning in an XML file, add a `tools:ignore="id"` attribute on the element containing the error, or one of its surrounding elements. You also need to define the namespace for the tools prefix on the root element in your document, next to the `xmlns:android` declaration:
`xmlns:tools="http://schemas.android.com/tools"`
To suppress a lint warning in a `build.gradle` file, add a section like this:
android {
lintOptions {
disable 'TypographyFractions','TypographyQuotes'
}
}
Here we specify a comma separated list of issue id's after the disable command. You can also use `warning` or `error` instead of `disable` to change the severity of issues.
To suppress lint warnings with a configuration XML file, create a file named `lint.xml` and place it at the root directory of the module in which it applies.
The format of the `lint.xml` file is something like the following:
<?xml version="1.0" encoding="UTF-8"?>
<lint>
<!-- Disable this given check in this project -->
<issue id="IconMissingDensityFolder" severity="ignore" />
<!-- Ignore the ObsoleteLayoutParam issue in the given files -->
<issue id="ObsoleteLayoutParam">
<ignore path="res/layout/activation.xml" />
<ignore path="res/layout-xlarge/activation.xml" />
</issue>
<!-- Ignore the UselessLeaf issue in the given file -->
<issue id="UselessLeaf">
<ignore path="res/layout/main.xml" />
</issue>
<!-- Change the severity of hardcoded strings to "error" -->
<issue id="HardcodedText" severity="error" />
</lint>
To suppress lint checks from the command line, pass the --ignore flag with a comma separated list of ids to be suppressed, such as:
`$ lint --ignore UnusedResources,UselessLeaf /my/project/path`
For more information, see http://g.co/androidstudio/suppressing-lint-warnings