This project is deprecated. There will be no new development on this project. Please use designtime layout attributes instead.
This project features a custom lint check for placerholders in your XML layout files.
A placeholder is a text which is used at design time but is replaced by a particular value at runtime. Assume you have a TextView which for example displays an order number. The order number is not present at design time but will be displayed at runtime.
While it's definitely bad practice to hard code strings into your layouts there are several good reasons where it make sense to use placeholder:
- get a meaningful overview of the layout
- see text appearance (font size, color, style, …)
- check correct wrapping
- …
A string is considered as a translatable entity within the layout. Strings are labels, which should be stored in your strings.xml.
Placeholders are used for layout purpose, they should fill a certain area of the screen in order to provide the developer on impression how the screen would look like at runtime. Since the are replaced by a particular value at runtime, there is no need to store them into your strings.xml
Android’s default checks already feature a check for hardcoded values. It basically checks if provided values in android:text and android:hint attributes start with @string/. This results in a majority of warnings, if you decide to use placeholders in your layouts.
To overcome these warnings this lint check is aware of a certain type of text which it also accepts: placeholder.
##What’s the syntax of a placeholder?
To express the usage of a placeholder, a placeholder is prefixed by „:“. The lint check won’t emit a warning if it detects a placeholder.
Note: Feel free to fork this project and change the syntax to whatever suits your needs.
Example:
<TextView android:text=":OrderNumber" />##How to install and run the custom check?
In order to install this check you need to place the compiled jar in your user's android/lint/ directory.
On Unix based systems you can simply use ./buildAndInstall for your convenience.
- Compile the rule
./gradlew clean assemble- Copy AndroidLintPlaceholderCheck-1.0.jar from build/libs/ to your user's android/lint/ directory. Note: On Unix based systems this is most likely ~/.android/lint/
mkdir ~/.android/lint/
cp build/libs/* ~/.android/lint/- Since the Android tools consider the above mentioned lint directory when executing checks you are all set to run the custom check for your project's layout files. However, since the default "HardcodedText" check is still in place you may want to ignore the default "HardcodedText" check to avoid I18N warnings. Since this custom check is an extension of the default "HardcodedText" check you won't loose any functionality. Run this check:
lint --check HardcodedTextWithPlaceholder