AlertIOS manages native iOS alerts, option sheets, and share dialogs
AppRegistry is the JS entry point to running all React Native apps. App
+
AppRegistry is the JS entry point to running all React Native apps. App
root components should register themselves with
AppRegistry.registerComponent, then the native system can load the bundle
for the app and then actually run the app when it's ready by invoking
diff --git a/docs/appstate.html b/docs/appstate.html
index 6109465f5a3..9d615f24ffe 100644
--- a/docs/appstate.html
+++ b/docs/appstate.html
@@ -1,4 +1,4 @@
-
AsyncStorage is a simple, asynchronous, persistent, global, key-value storage +
AsyncStorage is a simple, asynchronous, persistent, global, key-value storage system. It should be used instead of LocalStorage.
It is recommended that you use an abstraction on top of AsyncStorage instead of AsyncStorage directly for anything more than light usage since it operates globally.
This JS code is a simple facad over the native iOS implementation to provide diff --git a/docs/cameraroll.html b/docs/cameraroll.html index be8cf03c102..db60ce10bca 100644 --- a/docs/cameraroll.html +++ b/docs/cameraroll.html @@ -1,4 +1,4 @@ -
Saves the image with tag tag to the camera roll.
@param {string} tag - Can be any of the three kinds of tags we accept: +
Saves the image with tag tag to the camera roll.
@param {string} tag - Can be any of the three kinds of tags we accept: 1. URL 2. assets-library tag 3. tag returned from storing an image in memory
Invokes callback with photo identifier objects from the local camera
diff --git a/docs/datepickerios.html b/docs/datepickerios.html
index 2764371a96b..c38a11df306 100644
--- a/docs/datepickerios.html
+++ b/docs/datepickerios.html
@@ -1,4 +1,4 @@
-
Use DatePickerIOS to render a date/time picker (selector) on iOS. This is
+
Use DatePickerIOS to render a date/time picker (selector) on iOS. This is
a controlled component, so you must hook in to the onDateChange callback
and update the date prop in order for the component to update, otherwise
the user's change will be reverted immediately to reflect props.date as the
diff --git a/docs/getting-started.html b/docs/getting-started.html
index 0f990af4ef3..45f1f933893 100644
--- a/docs/getting-started.html
+++ b/docs/getting-started.html
@@ -1,4 +1,4 @@
-
Our first React Native implementation is ReactKit, targeting iOS. We are also
+
Our first React Native implementation is ReactKit, targeting iOS. We are also
working on an Android implementation which we will release later. ReactKit
apps are built using the React JS framework, and render directly to
native UIKit elements using a fully asynchronous architecture. There is no
diff --git a/docs/image.html b/docs/image.html
index d8893821a2b..5844de8bffe 100644
--- a/docs/image.html
+++ b/docs/image.html
@@ -1,4 +1,4 @@
-
A react component for displaying different types of images, +
A react component for displaying different types of images, including network images, static resources, temporary local images, and images from local disk, such as the camera roll.
Example usage:
InteractionManager allows long-running work to be scheduled after any +
InteractionManager allows long-running work to be scheduled after any interactions/animations have completed. In particular, this allows JavaScript animations to run smoothly.
Applications can schedule tasks to run after interactions with the following:
ListView - A core component designed for efficient display of vertically +
ListView - A core component designed for efficient display of vertically
scrolling lists of changing data. The minimal API is to create a
ListView.DataSource, populate it with a simple array of data blobs, and
instantiate a ListView component with that data source and a renderRow
diff --git a/docs/mapview.html b/docs/mapview.html
index 7590952c1eb..8af3866d77d 100644
--- a/docs/mapview.html
+++ b/docs/mapview.html
@@ -1,4 +1,4 @@
-
Insets for the map's legal label, originally at bottom left of the map. +
Insets for the map's legal label, originally at bottom left of the map.
See EdgeInsetsPropType.js for more information.
Maximum size of area that can be displayed.
Minimum size of area that can be displayed.
Callback that is called continuously when the user is dragging the map.
Callback that is called once, when the user is done moving the map.
When this property is set to true and a valid camera is associated
with the map, the camera’s pitch angle is used to tilt the plane
of the map. When this property is set to false, the camera’s pitch
diff --git a/docs/nativemodulesios.html b/docs/nativemodulesios.html
new file mode 100644
index 00000000000..35b5cbd7df3
--- /dev/null
+++ b/docs/nativemodulesios.html
@@ -0,0 +1,75 @@
+
Sometimes an app needs access to platform API, and React Native doesn't have a corresponding wrapper yet. This is a more advanced guide that shows how to build a native module. It assumes the reader knows Objective-C (Swift is not supported yet) and core libraries (Foundation, UIKit).
This guide will use iOS Calendar API example. Let's say we would like to be able to access iOS calendar from JavaScript.
Native module is just an Objectve-C class that implements RCTBridgeModule protocol.
React Native will not expose any methods of RCTCalendarManager to JavaScript unless explicitly asked. Fortunately this is pretty easy with RCT_EXPORT:
Now from your JavaScript file you can call the method like this:
Notice that the module name doesn't have RCT prefix. Exported method name was generated from first part of Objective-C selector. Sometimes it results in a non-idiomatic JavaScript name (like the one in our example). You can change the name by supplying an optional argument to RCT_EXPORT, e.g. RCT_EXPORT("addEvent").
The return type of the method should always be void. React Native bridge is asynchronous, so the only way to pass result to JavaScript is by using callbacks or emitting events (see below).
React Native supports several types of arguments that can be passed from JavaScript code to native module:
React NativeNSString)NSInteger, float, NSNumber)BOOL, NSNumber)NSArray) of any types from this listNSDictionary) with string keys and values of any type from this listRCTResponseSenderBlock)In our CalendarManager example, if we want to pass event date to native, we have to convert it to a string or a number:
As CalendarManager.addEvent method gets more and more complex, the number of arguments will grow. Some of them might be optional. In this case it's worth considering changing the API a little bit to accept a dictionary of event attributes, like this:
and call it from JavaScript:
NOTE about array and map - React Native doesn't provide any guarantees about the types of values in these structures. Your native module might expect array of strings, but if JavaScript calls your method with an array that contains number and string you'll get NSArray with NSNumber and NSString. It's developer's responsibility to check array/map values types.
WARNING: This section is even more experimental than others, we don't have a set of best practices around callbacks yet.
Native module also supports a special kind of argument - callback. In most cases it is used to provide function call result to JavaScript.
RCTResponseSenderBlock accepts only one argument - array of arguments to pass to JavaScript callback. In this case we use node's convention to set first argument to error and the rest - to the result of the function.
Native module is supposed to invoke callback only once. It can, however, store the callback as an ivar and invoke it later. This pattern is often used to wrap iOS APIs that require delegate. See RCTAlertManager.
If you want to pass error-like object to JavaScript, use RCTMakeError from RCTUtils.h.
The native module should not have any assumptions about what thread it is being called on. React Native invokes native modules methods on a separate serial GCD queue, but this is an implementation detail and might change. If the native module needs to call main-thread-only iOS API, it should schedule the operation on the main queue:
The same way if the operation can take a long time to complete, the native module should not block. It is a good idea to use dispatch_async to schedule expensive work on background queue.
Native module can export constants that are instantly available to JavaScript at runtime. This is useful to export some initial data that would otherwise require a bridge round-trip.
JavaScript can use this value right away:
Note that the constants are exported only at initialization time, so if you change constantsToExport value at runtime it won't affect JavaScript environment.
The native module can signal events to JavaScript without being invoked directly. The easiest way to do this is to use eventDispatcher:
JavaScript code can subscribe to these events:
For more examples of sending events to JavaScript, see RCTLocationObserver.
NavigatorIOS wraps UIKit navigation and allows you to add back-swipe +
NavigatorIOS wraps UIKit navigation and allows you to add back-swipe functionality across your app.
A route is an object used to describe each page in the navigator. The first
route is provided to NavigatorIOS as initialRoute:
NetInfo exposes info about online/offline status
== iOS Reachability
Asyncronously determine if the device is online and on a cellular network.
NetInfo exposes info about online/offline status
== iOS Reachability
Asyncronously determine if the device is online and on a cellular network.
One of React Native goal is to be a playground where we can experiment with different architectures and crazy ideas. Since browsers are not flexible enough, we had no choice but to reimplement the entire stack. In the places that we did not intend to change, we tried to be as faithful as possible to the browser APIs. The networking stack is a great example.
XMLHttpRequest API is implemented on-top of iOS networking apis. The notable difference from web is the security model: you can read from arbitrary websites on the internet since there is no concept of CORS.
One of React Native goal is to be a playground where we can experiment with different architectures and crazy ideas. Since browsers are not flexible enough, we had no choice but to reimplement the entire stack. In the places that we did not intend to change, we tried to be as faithful as possible to the browser APIs. The networking stack is a great example.
XMLHttpRequest API is implemented on-top of iOS networking apis. The notable difference from web is the security model: you can read from arbitrary websites on the internet since there is no concept of CORS.
PixelRatio class gives access to the device pixel density.
There are a few use cases for using PixelRatio:
A width of 1 is actually pretty thick on an iPhone 4+, we can do one that's +
PixelRatio class gives access to the device pixel density.
There are a few use cases for using PixelRatio:
A width of 1 is actually pretty thick on an iPhone 4+, we can do one that's
thinner using a width of 1 / PixelRatio.get(). It's a technique that works
on all the devices independent of their pixel density.
You should get a higher resolution image if you are on a high pixel density device. A good rule of thumb is to multiply the size of the image you display diff --git a/docs/pixels.html b/docs/pixels.html index 4ef4f38dc48..fc88617a4cd 100644 --- a/docs/pixels.html +++ b/docs/pixels.html @@ -1,4 +1,4 @@ -
In iOS, you can specify positions and dimensions for elements with arbitrary precision, for example 29.674825. But, ultimately the physical display only have a fixed number of pixels, for example 640×960 for iphone 4 or 750×1334 for iphone 6. iOS tries to be as faithful as possible to the user value by spreading one original pixel into multiple ones to trick the eye. The downside of this technique is that it makes the resulting element look blurry.
In practice, we found out that developers do not want this feature and they have to work around it by doing manual rounding in order to avoid having blurry elements. In React Native, we are rounding all the pixels automatically.
We have to be careful when to do this rounding. You never want to work with rounded and unrounded values at the same time as you're going to accumulate rounding errors. Having even one rounding error is deadly because a one pixel border may vanish or be twice as big.
In React Native, everything in JS and within the layout engine work with arbitrary precision numbers. It's only when we set the position and dimensions of the native element on the main thread that we round. Also, rounding is done relative to the root rather than the parent, again to avoid accumulating rounding errors.
A width of 1 is actually 2 physical pixels thick on an iPhone 4 and 3 physical pixels thick on an iphone 6+. If you want to display a line that's as thin as possible, you can use a width of 1 / PixelRatio.get(). It's a technique that works on all the devices independent of their pixel density.
You should get a higher resolution image if you are on a high pixel density device. A good rule of thumb is to multiply the size of the image you display by the pixel ratio.
In iOS, you can specify positions and dimensions for elements with arbitrary precision, for example 29.674825. But, ultimately the physical display only have a fixed number of pixels, for example 640×960 for iphone 4 or 750×1334 for iphone 6. iOS tries to be as faithful as possible to the user value by spreading one original pixel into multiple ones to trick the eye. The downside of this technique is that it makes the resulting element look blurry.
In practice, we found out that developers do not want this feature and they have to work around it by doing manual rounding in order to avoid having blurry elements. In React Native, we are rounding all the pixels automatically.
We have to be careful when to do this rounding. You never want to work with rounded and unrounded values at the same time as you're going to accumulate rounding errors. Having even one rounding error is deadly because a one pixel border may vanish or be twice as big.
In React Native, everything in JS and within the layout engine work with arbitrary precision numbers. It's only when we set the position and dimensions of the native element on the main thread that we round. Also, rounding is done relative to the root rather than the parent, again to avoid accumulating rounding errors.
A width of 1 is actually 2 physical pixels thick on an iPhone 4 and 3 physical pixels thick on an iphone 6+. If you want to display a line that's as thin as possible, you can use a width of 1 / PixelRatio.get(). It's a technique that works on all the devices independent of their pixel density.
You should get a higher resolution image if you are on a high pixel density device. A good rule of thumb is to multiply the size of the image you display by the pixel ratio.
Component that wraps platform ScrollView while providing +
Component that wraps platform ScrollView while providing integration with touch locking "responder" system.
Doesn't yet support other contained responders from blocking this scroll view from becoming the responder.
When true, the scroll view bounces horizontally when it reaches the end even if the content is smaller than the scroll view itself. The default diff --git a/docs/sliderios.html b/docs/sliderios.html index 01b1836d33f..f447c50ef95 100644 --- a/docs/sliderios.html +++ b/docs/sliderios.html @@ -1,4 +1,4 @@ -
Callback called when the user finishes changing the value (e.g. when +
Callback called when the user finishes changing the value (e.g. when the slider is released).
Callback continuously called while the user is dragging the slider.
Used to style and layout the Slider. See StyleSheet.js and
ViewStylePropTypes.js for more info.
Initial value of the slider. The value should be between 0 and 1. Default value is 0.
This is not a controlled component, e.g. if you don't update diff --git a/docs/statusbarios.html b/docs/statusbarios.html index fa9382d7f21..e1cfe3fc2f4 100644 --- a/docs/statusbarios.html +++ b/docs/statusbarios.html @@ -1,4 +1,4 @@ -
The way to declare styles in React Native is the following:
A StyleSheet is an abstraction similar to CSS StyleSheets
Create a new StyleSheet:
A StyleSheet is an abstraction similar to CSS StyleSheets
Create a new StyleSheet:
Use SwitchIOS to render a boolean input on iOS. This is
+
Use SwitchIOS to render a boolean input on iOS. This is
a controlled component, so you must hook in to the onValueChange callback
and update the value prop in order for the component to update, otherwise
the user's change will be reverted immediately to reflect props.value as the
diff --git a/docs/tabbarios.html b/docs/tabbarios.html
index dc7ac3dc154..6758dd10d70 100644
--- a/docs/tabbarios.html
+++ b/docs/tabbarios.html
@@ -1,4 +1,4 @@
-
A react component for displaying text which supports nesting, +
A react component for displaying text which supports nesting,
styling, and touch handling. In the following example, the nested title and
body text will inherit the fontFamily from styles.baseText, but the title
provides its own additional styles. The title and body will stack on top of
diff --git a/docs/textinput.html b/docs/textinput.html
index 74849002e87..901636f6783 100644
--- a/docs/textinput.html
+++ b/docs/textinput.html
@@ -1,4 +1,4 @@
-
A foundational component for inputting text into the app via a +
A foundational component for inputting text into the app via a keyboard. Props provide configurability for several features, such as auto- correction, auto-capitalization, placeholder text, and different keyboard types, such as a numeric keypad.
The simplest use case is to plop down a TextInput and subscribe to the
diff --git a/docs/timers.html b/docs/timers.html
index 27e3b330f8c..ad5c485d9a9 100644
--- a/docs/timers.html
+++ b/docs/timers.html
@@ -1,4 +1,4 @@
-
Timers are an important part of an application and React Native implements the browser timers.
requestAnimationFrame(fn) is the exact equivalent of setTimeout(fn, 0), they are triggered right after the screen has been flushed.
setImmediate is executed at the end of the current JavaScript execution block, right before sending the batched response back to native. Note that if you call setImmediate within a setImmediate callback, it will be executed right away, it won't yield back to native in between.
The Promise implementation uses setImmediate as its asynchronicity primitive.
One reason why well-built native apps feel so smooth is by avoiding expensive operations during interactions and animations. In React Native, we currently have a limitation that there is only a single JS execution thread, but you can use InteractionManager to make sure long-running work is scheduled to start after any interactions/animations have completed.
Applications can schedule tasks to run after interactions with the following:
Timers are an important part of an application and React Native implements the browser timers.
requestAnimationFrame(fn) is the exact equivalent of setTimeout(fn, 0), they are triggered right after the screen has been flushed.
setImmediate is executed at the end of the current JavaScript execution block, right before sending the batched response back to native. Note that if you call setImmediate within a setImmediate callback, it will be executed right away, it won't yield back to native in between.
The Promise implementation uses setImmediate as its asynchronicity primitive.
One reason why well-built native apps feel so smooth is by avoiding expensive operations during interactions and animations. In React Native, we currently have a limitation that there is only a single JS execution thread, but you can use InteractionManager to make sure long-running work is scheduled to start after any interactions/animations have completed.
Applications can schedule tasks to run after interactions with the following:
Compare this to other scheduling alternatives:
The touch handling system considers one or more active touches to be an 'interaction' and will delay runAfterInteractions() callbacks until all touches have ended or been cancelled.
InteractionManager also allows applications to register animations by creating an interaction 'handle' on animation start, and clearing it upon completion: