ios-res-tool

ios-res-tool is a collection of ruby scripts to help you work with iOS resources:

• Import from Android <string>, <string-array>, <plurals> resources
• Export to CSV file
• Re-import from previously exported CSV file
• Generate R.swift to mimic Android R.java
• Generate R+assets.swift to access .xcassets

Why use this tool?

If you are doing cross platform development, then you known it is painful to do localization strings management, as iOS and Android are using different format.

Personally I find Android resource management is much better than iOS's, and the string definition is much clear with Android, especially for array and plurals. That's why I need a tool to do strings conversion from Android to iOS.

There are many tools, even some on-line services to solve this problem. But I find they are more or less having some shortcomings, mostly:

• no <string-array> support
• no <plurals> support
• no type-safe way to access resource for iOS development
• no CSV import / export

I want a tool to do these all, and can do it in batch, so I can put it into build script if needed. Thus why I write this script by myself.

Usage

Usage: ios-strings.rb [options]
    --import-android=DIR         Import from Andrord resources directory
    --import-ios=DIR             Import from iOS resources directory
    --import-csv=FILE            Import from CSV file
    --export-ios=DIR             Export to iOS resources directory
    --export-csv=FILE            Export to CSV file
    --export-swift               Generate R.swift, require import or export iOS options
    --copy-base=LOCALE           Copy base resource to the specified locale
    --help                       Show this message

Supported Android resource types

The following Android resource types are supported by this tool:

Android xml tag	iOS file
string	Generate to Localizable.strings
string-array	Generate to LocalizableArray.strings
plurals	Generate to Localizable.stringsdict

For every language, Android side may have multiple .xml files, all will be merged into single file on iOS. The iOS file will be put into proper language directory, such as Base.lproj, zh-Hant.lproj, etc...

Import from Android

Take the following Android project for example:

~/android_app
+-- src/
+-- res/
    +-- values/
    |   +-- strings.xml
    |   +-- strings_about.xml
    |   +-- strings_menu.xml
    |   +-- arrays.xml
    |   +-- plurals.xml
    +-- values-zh-rTW/
        +-- strings.xml
        +-- plurals.xml

And iOS project before running the tool:

~/ios_app
+-- src/
+-- res/

Then you can run the tool for ios_app:

ruby ios-strings.rb --import-android=~/android_app/res --export-ios=~/ios_app/res --export-swift

And the iOS project will look like

~/ios_app
+-- src/
+-- res/
    +-- R.swift
    +-- Base.lproj
    |   +-- Localizable.strings
    |   +-- LocalizableArray.strings
    |   +-- Localizable.stringsdict
    +-- zh-Hant.lproj
        +-- Localizable.strings
        +-- LocalizableArray.strings
        +-- Localizable.stringsdict

Type-safe access to strings

The tools generate a R.swift that mimic Android R.java, the generated code is type-safe and IDE friendly:

The generated R.swift looks like:

struct R {
    enum string : String {
        case btn_ok
        ...
    }
    enum array : String {
        case menu_list
        ...
    }
    enum plurals : String {
        case item_count
        ...
    }
}

swift expression	swift type	Usage
R.string.btn_ok	R.string	enum case, you can get the key string by .rawValue
R.string.btn_ok^	String	To get the localized string
R.array.menu_list	R.array	enum case, you can get the key string by .rawValue
R.array.menu_list^	[String]	To get the localized string array
R.array.menu_list[2]	String	To get 3rd item of the localized string array (it's zero based index)
R.plurals.item_count	R.plurals	enum case, you can get the key string by .rawValue
R.plurals.item_count[5]	String	To get the localized string with quantity 5

The ^ and [] operator for R.swift are overloaded to provide access to the strings.

Export to CSV file

The ios-strings.rb can also export resources to one CSV file, for review or other purpose, please try:

ruby ios-strings.rb --import-ios=~/ios_app/res --export-csv=report.csv

Or directly from Android resources:

ruby ios-strings.rb --import-android=~/android_app/res --export-csv=report.csv

Re-import from CSV file

After you review the exported CSV file, you can re-import the file if you have make some modifications:

ruby ios-strings.rb --import-csv=report.csv --export-ios=~/ios_app/res

Type-safe access to assets

Another tool ios-assets.rb will generate R+assets.swift as extension to R.swift, that provides type-safe and IDE friendly access to the image assets. To run the tool:

ruby ios-assets.rb --import=~/ios_app/res

The generated R+assets.swift looks like:

extension R {
    enum image : String {
        case icon_logo
        ...
    }
}

swift expression	swift type	Usage
R.image.icon_logo	R.image	enum case, you can get the key string by .rawValue
R.image.icon_logo^	UIImage	To get the image from assets

The postfix ^ operator for R+assets.swift are overloaded to provide access to the assets.