purescript-reactnative

Purescript bindings for react-native

• Movie example project
• bower install purescript-reactnative --save

Goals

React-native is a fast moving javascript project which is frequently released (monthly at the time of writing). Much too fast for me to realistically keep all the purescript bindings continually up-to-date, so the goals are:

• Keep up to date with purescript language releases.

• Keep the official React Native docs as the best place to go for help. This will be acheived by:

• Using record types for property passing.

• Use newtype | foreign import data + smart constructors for property types.

• Have unsafe versions of all the component functions, so if the library is lagging behind or the component does not yet have a safe version, it's still possible to use the library without too much hassle.

• Stay event framework agnostic. This is acheived by using EffFnX to model the event callbacks. There will be additional libraries for your favourite action library - e.g. purescript-reactnative-thermite I have also made a very small and simple library for dispatching react actions purescript-react-simpelaction.

Examples and Naming conventions

All component functions follow the naming convention of:

• image - The most common properties
• image_ - Only mandatory properties
• image' - Mandatory properties and all optional properties
• imageU - Unsafe, takes any properties

Enum property types will either be accessible through functions with the name of the enum:

newtype FlexDirection = FlexDirection String

row :: FlexDirection
row = FlexDirection "row"

rowReverse :: FlexDirection
rowReverse = FlexDirection "row-reverse"

column :: FlexDirection
column = FlexDirection "column"

columnReverse :: FlexDirection
columnReverse = FlexDirection "column-reverse"`

or a record which has a field for each value in the enum:

newtype KeyboardDismissMode = KeyboardDismissMode String
keyboardDismissMode :: {
    none :: KeyboardDismissMode
  , interactive :: KeyboardDismissMode
  , onDrag :: KeyboardDismissMode
}
keyboardDismissMode = {
    none: KeyboardDismissMode "none"
  , interactive: KeyboardDismissMode "interactive"
  , onDrag: KeyboardDismissMode "on-drag"
}

If you want to examples check out the code in the purescript-reactnative port of the Movies example app which comes with the react-native source code.

https://github.com/doolse/purescript-reactnative-example

Styles

Styles are defined using arrays of StyleProps and you can create a stylesheet simply by creating a record which contains these styles defined with staticStyles:

sheet :: { searchBar :: Styles
, searchBarInput :: Styles
, spinner :: Styles
, icon :: Styles
}
sheet = {
  searchBar: staticStyles [
    flexDirection row,
    alignItems center,
    backgroundColor $ rgbi 0xa9a9a9,
    height 56
  ],
  searchBarInput: staticStyles [
    flex 1,
    fontSize 20,
    fontWeight bold,
    color white,
    height 50,
    padding 0,
    backgroundColor transparent
  ],
  spinner: staticStyles [
    width 30,
    height 30,
    marginRight 16
  ],
  icon: staticStyles [
    width 24,
    height 24,
    marginHorizontal 8
  ]
}

Platform specific code

The decision to not do anything special with the type system concerning platform specific components is because:

• a) Usually it very obvious from the component name
• b) It would be a significant amount of extra work and type signature noise and I don't think the benefits justify it.

Having said that, platform specific properties have been separated into sub properties for clarity. For example:

type ViewProps eff = {
    style :: Styles
    -- More platform neutral properties
  , ios :: Prop {
        shouldRasterizeIOS :: Boolean
    },
  , android :: Prop {
        needsOffscreenAlphaCompositing :: Boolean
    }
}

Component support table

The plan is to initially support a subset of the components fully, and provide unsafe functions for many of the others. Type safe versions of the components are created based off the react-native documentation, this table shows the current status:

Component	Version
View	0.39
Text	0.39
TextInput	0.39
Switch	0.39
Touchable*	0.39
Picker	0.39
Slider	0.39
ActivityIndicator	0.39
ListView	0.39
ScrollView	0.39
Image	0.39
RefreshControl	0.39
Button	0.39
Navigator	0.39 *
NavigatorIOS	0.39 *
DrawerLayoutAndroid	0.39
ToolbarAndroid	0.39
DatePickerIOS	-
KeyboardAvoidingView	-
MapView	-
Modal	-
ProgressBarAndroid	-
ProgressViewIOS	-
SegmentedControlIOS	-
StatusBar	-
SnapshotViewIOS	-
TabBarIOS	-
TabBarIOSItem	-
ViewPagerAndroid	-
WebView	-

API	Version
alert	0.39
color	0.39
ListViewDataSource	0.39
NavigationExpiremental	0.39 *

Anything marked with * may not have 100% coverage of API calls yet.

Contributors

Jolse Maginnis (doolse@gmail.com @doolse2) Jens Krause (@sectore)