/** * Copyright (c) 2015-present, Facebook, Inc. * All rights reserved. * * This source code is licensed under the BSD-style license found in the * LICENSE file in the root directory of this source tree. An additional grant * of patent rights can be found in the PATENTS file in the same directory. * * @providesModule View * @flow */ 'use strict'; const EdgeInsetsPropType = require('EdgeInsetsPropType'); const NativeMethodsMixin = require('react/lib/NativeMethodsMixin'); const PropTypes = require('react/lib/ReactPropTypes'); const React = require('React'); const ReactNativeStyleAttributes = require('ReactNativeStyleAttributes'); const ReactNativeViewAttributes = require('ReactNativeViewAttributes'); const StyleSheetPropType = require('StyleSheetPropType'); const UIManager = require('UIManager'); const ViewStylePropTypes = require('ViewStylePropTypes'); const requireNativeComponent = require('requireNativeComponent'); const stylePropType = StyleSheetPropType(ViewStylePropTypes); const AccessibilityTraits = [ 'none', 'button', 'link', 'header', 'search', 'image', 'selected', 'plays', 'key', 'text', 'summary', 'disabled', 'frequentUpdates', 'startsMedia', 'adjustable', 'allowsDirectInteraction', 'pageTurn', ]; const AccessibilityComponentType = [ 'none', 'button', 'radiobutton_checked', 'radiobutton_unchecked', ]; const forceTouchAvailable = (UIManager.RCTView.Constants && UIManager.RCTView.Constants.forceTouchAvailable) || false; const statics = { AccessibilityTraits, AccessibilityComponentType, /** * Is 3D Touch / Force Touch available (i.e. will touch events include `force`) * @platform ios */ forceTouchAvailable, }; /** * The most fundamental component for building a UI, `View` is a container that supports layout with * [flexbox](/react-native/docs/flexbox.html), [style](/react-native/docs/style.html), * [some touch handling](/react-native/docs/handling-touches.html), and * [accessibility](/react-native/docs/accessibility.html) controls. `View` maps directly to the * native view equivalent on whatever platform React Native is running on, whether that is a * `UIView`, `
`, `android.view`, etc. * * `View` is designed to be nested inside other views and can have 0 to many children of any type. * * This example creates a `View` that wraps two colored boxes and a text component in a row with * padding. * * ```javascript * class ViewColoredBoxesWithText extends Component { * render() { * return ( * * * * Hello World! * * ); * } * } * ``` * * > `View`s are designed to be used with [`StyleSheet`](/react-native/docs/style.html) for clarity * > and performance, although inline styles are also supported. * * ### Synthetic Touch Events * * For `View` responder props (e.g., `onResponderMove`), the synthetic touch event passed to them * are of the following form: * * - `nativeEvent` * - `changedTouches` - Array of all touch events that have changed since the last event. * - `identifier` - The ID of the touch. * - `locationX` - The X position of the touch, relative to the element. * - `locationY` - The Y position of the touch, relative to the element. * - `pageX` - The X position of the touch, relative to the root element. * - `pageY` - The Y position of the touch, relative to the root element. * - `target` - The node id of the element receiving the touch event. * - `timestamp` - A time identifier for the touch, useful for velocity calculation. * - `touches` - Array of all current touches on the screen. */ const View = React.createClass({ // TODO: We should probably expose the mixins, viewConfig, and statics publicly. For example, // one of the props is of type AccessibilityComponentType. That is defined as a const[] above, // but it is not rendered by the docs, since `statics` below is not rendered. So its Possible // values had to be hardcoded. mixins: [NativeMethodsMixin], /** * `NativeMethodsMixin` will look for this when invoking `setNativeProps`. We * make `this` look like an actual native component class. */ viewConfig: { uiViewClassName: 'RCTView', validAttributes: ReactNativeViewAttributes.RCTView }, statics: { ...statics, }, propTypes: { /** * When `true`, indicates that the view is an accessibility element. By default, * all the touchable elements are accessible. */ accessible: PropTypes.bool, /** * Overrides the text that's read by the screen reader when the user interacts * with the element. By default, the label is constructed by traversing all the * children and accumulating all the `Text` nodes separated by space. */ accessibilityLabel: PropTypes.node, /** * Indicates to accessibility services to treat UI component like a * native one. Works for Android only. * * Possible values are one of: * * - `'none'` * - `'button'` * - `'radiobutton_checked'` * - `'radiobutton_unchecked'` * * @platform android */ accessibilityComponentType: PropTypes.oneOf(AccessibilityComponentType), /** * Indicates to accessibility services whether the user should be notified * when this view changes. Works for Android API >= 19 only. * Possible values: * * - `'none'` - Accessibility services should not announce changes to this view. * - `'polite'`- Accessibility services should announce changes to this view. * - `'assertive'` - Accessibility services should interrupt ongoing speech to immediately announce changes to this view. * * See the [Android `View` docs](http://developer.android.com/reference/android/view/View.html#attr_android:accessibilityLiveRegion) * for reference. * * @platform android */ accessibilityLiveRegion: PropTypes.oneOf([ 'none', 'polite', 'assertive', ]), /** * Controls how view is important for accessibility which is if it * fires accessibility events and if it is reported to accessibility services * that query the screen. Works for Android only. * * Possible values: * * - `'auto'` - The system determines whether the view is important for accessibility - * default (recommended). * - `'yes'` - The view is important for accessibility. * - `'no'` - The view is not important for accessibility. * - `'no-hide-descendants'` - The view is not important for accessibility, * nor are any of its descendant views. * * See the [Android `importantForAccessibility` docs](http://developer.android.com/reference/android/R.attr.html#importantForAccessibility) * for reference. * * @platform android */ importantForAccessibility: PropTypes.oneOf([ 'auto', 'yes', 'no', 'no-hide-descendants', ]), /** * Provides additional traits to screen reader. By default no traits are * provided unless specified otherwise in element. * * You can provide one trait or an array of many traits. * * Possible values for `AccessibilityTraits` are: * * - `'none'` - The element has no traits. * - `'button'` - The element should be treated as a button. * - `'link'` - The element should be treated as a link. * - `'header'` - The element is a header that divides content into sections. * - `'search'` - The element should be treated as a search field. * - `'image'` - The element should be treated as an image. * - `'selected'` - The element is selected. * - `'plays'` - The element plays sound. * - `'key'` - The element should be treated like a keyboard key. * - `'text'` - The element should be treated as text. * - `'summary'` - The element provides app summary information. * - `'disabled'` - The element is disabled. * - `'frequentUpdates'` - The element frequently changes its value. * - `'startsMedia'` - The element starts a media session. * - `'adjustable'` - The element allows adjustment over a range of values. * - `'allowsDirectInteraction'` - The element allows direct touch interaction for VoiceOver users. * - `'pageTurn'` - Informs VoiceOver that it should scroll to the next page when it finishes reading the contents of the element. * * See the [Accessibility guide](/react-native/docs/accessibility.html#accessibilitytraits-ios) * for more information. * * @platform ios */ accessibilityTraits: PropTypes.oneOfType([ PropTypes.oneOf(AccessibilityTraits), PropTypes.arrayOf(PropTypes.oneOf(AccessibilityTraits)), ]), /** * When `accessible` is true, the system will try to invoke this function * when the user performs accessibility tap gesture. */ onAccessibilityTap: PropTypes.func, /** * When `accessible` is `true`, the system will invoke this function when the * user performs the magic tap gesture. */ onMagicTap: PropTypes.func, /** * Used to locate this view in end-to-end tests. * * > This disables the 'layout-only view removal' optimization for this view! */ testID: PropTypes.string, /** * For most touch interactions, you'll simply want to wrap your component in * `TouchableHighlight` or `TouchableOpacity`. Check out `Touchable.js`, * `ScrollResponder.js` and `ResponderEventPlugin.js` for more discussion. */ /** * The View is now responding for touch events. This is the time to highlight and show the user * what is happening. * * `View.props.onResponderGrant: (event) => {}`, where `event` is a synthetic touch event as * described above. */ onResponderGrant: PropTypes.func, /** * The user is moving their finger. * * `View.props.onResponderMove: (event) => {}`, where `event` is a synthetic touch event as * described above. */ onResponderMove: PropTypes.func, /** * Another responder is already active and will not release it to that `View` asking to be * the responder. * * `View.props.onResponderReject: (event) => {}`, where `event` is a synthetic touch event as * described above. */ onResponderReject: PropTypes.func, /** * Fired at the end of the touch. * * `View.props.onResponderRelease: (event) => {}`, where `event` is a synthetic touch event as * described above. */ onResponderRelease: PropTypes.func, /** * The responder has been taken from the `View`. Might be taken by other views after a call to * `onResponderTerminationRequest`, or might be taken by the OS without asking (e.g., happens * with control center/ notification center on iOS) * * `View.props.onResponderTerminate: (event) => {}`, where `event` is a synthetic touch event as * described above. */ onResponderTerminate: PropTypes.func, /** * Some other `View` wants to become responder and is asking this `View` to release its * responder. Returning `true` allows its release. * * `View.props.onResponderTerminationRequest: (event) => {}`, where `event` is a synthetic touch * event as described above. */ onResponderTerminationRequest: PropTypes.func, /** * Does this view want to become responder on the start of a touch? * * `View.props.onStartShouldSetResponder: (event) => [true | false]`, where `event` is a * synthetic touch event as described above. */ onStartShouldSetResponder: PropTypes.func, /** * If a parent `View` wants to prevent a child `View` from becoming responder on a touch start, * it should have this handler which returns `true`. * * `View.props.onStartShouldSetResponderCapture: (event) => [true | false]`, where `event` is a * synthetic touch event as described above. */ onStartShouldSetResponderCapture: PropTypes.func, /** * Does this view want to "claim" touch responsiveness? This is called for every touch move on * the `View` when it is not the responder. * * `View.props.onMoveShouldSetResponder: (event) => [true | false]`, where `event` is a * synthetic touch event as described above. */ onMoveShouldSetResponder: PropTypes.func, /** * If a parent `View` wants to prevent a child `View` from becoming responder on a move, * it should have this handler which returns `true`. * * `View.props.onMoveShouldSetResponderCapture: (event) => [true | false]`, where `event` is a * synthetic touch event as described above. */ onMoveShouldSetResponderCapture: PropTypes.func, /** * This defines how far a touch event can start away from the view. * Typical interface guidelines recommend touch targets that are at least * 30 - 40 points/density-independent pixels. * * For example, if a touchable view has a height of 20 the touchable height can be extended to * 40 with `hitSlop={{top: 10, bottom: 10, left: 0, right: 0}}` * * > The touch area never extends past the parent view bounds and the Z-index * > of sibling views always takes precedence if a touch hits two overlapping * > views. */ hitSlop: EdgeInsetsPropType, /** * Invoked on mount and layout changes with: * * `{nativeEvent: { layout: {x, y, width, height}}}` * * This event is fired immediately once the layout has been calculated, but * the new layout may not yet be reflected on the screen at the time the * event is received, especially if a layout animation is in progress. */ onLayout: PropTypes.func, /** * Controls whether the `View` can be the target of touch events. * * - `'auto'`: The View can be the target of touch events. * - `'none'`: The View is never the target of touch events. * - `'box-none'`: The View is never the target of touch events but it's * subviews can be. It behaves like if the view had the following classes * in CSS: * ``` * .box-none { * pointer-events: none; * } * .box-none * { * pointer-events: all; * } * ``` * - `'box-only'`: The view can be the target of touch events but it's * subviews cannot be. It behaves like if the view had the following classes * in CSS: * ``` * .box-only { * pointer-events: all; * } * .box-only * { * pointer-events: none; * } * ``` * > Since `pointerEvents` does not affect layout/appearance, and we are * > already deviating from the spec by adding additional modes, we opt to not * > include `pointerEvents` on `style`. On some platforms, we would need to * > implement it as a `className` anyways. Using `style` or not is an * > implementation detail of the platform. */ pointerEvents: PropTypes.oneOf([ 'box-none', 'none', 'box-only', 'auto', ]), style: stylePropType, /** * This is a special performance property exposed by `RCTView` and is useful * for scrolling content when there are many subviews, most of which are * offscreen. For this property to be effective, it must be applied to a * view that contains many subviews that extend outside its bound. The * subviews must also have `overflow: hidden`, as should the containing view * (or one of its superviews). */ removeClippedSubviews: PropTypes.bool, /** * Whether this `View` should render itself (and all of its children) into a * single hardware texture on the GPU. * * On Android, this is useful for animations and interactions that only * modify opacity, rotation, translation, and/or scale: in those cases, the * view doesn't have to be redrawn and display lists don't need to be * re-executed. The texture can just be re-used and re-composited with * different parameters. The downside is that this can use up limited video * memory, so this prop should be set back to false at the end of the * interaction/animation. * * @platform android */ renderToHardwareTextureAndroid: PropTypes.bool, /** * Whether this `View` should be rendered as a bitmap before compositing. * * On iOS, this is useful for animations and interactions that do not * modify this component's dimensions nor its children; for example, when * translating the position of a static view, rasterization allows the * renderer to reuse a cached bitmap of a static view and quickly composite * it during each frame. * * Rasterization incurs an off-screen drawing pass and the bitmap consumes * memory. Test and measure when using this property. * * @platform ios */ shouldRasterizeIOS: PropTypes.bool, /** * Views that are only used to layout their children or otherwise don't draw * anything may be automatically removed from the native hierarchy as an * optimization. Set this property to `false` to disable this optimization and * ensure that this `View` exists in the native view hierarchy. * * @platform android */ collapsable: PropTypes.bool, /** * Whether this `View` needs to rendered offscreen and composited with an alpha * in order to preserve 100% correct colors and blending behavior. The default * (`false`) falls back to drawing the component and its children with an alpha * applied to the paint used to draw each element instead of rendering the full * component offscreen and compositing it back with an alpha value. This default * may be noticeable and undesired in the case where the `View` you are setting * an opacity on has multiple overlapping elements (e.g. multiple overlapping * `View`s, or text and a background). * * Rendering offscreen to preserve correct alpha behavior is extremely * expensive and hard to debug for non-native developers, which is why it is * not turned on by default. If you do need to enable this property for an * animation, consider combining it with renderToHardwareTextureAndroid if the * view **contents** are static (i.e. it doesn't need to be redrawn each frame). * If that property is enabled, this View will be rendered off-screen once, * saved in a hardware texture, and then composited onto the screen with an alpha * each frame without having to switch rendering targets on the GPU. * * @platform android */ needsOffscreenAlphaCompositing: PropTypes.bool, }, render: function() { // WARNING: This method will not be used in production mode as in that mode we // replace wrapper component View with generated native wrapper RCTView. Avoid // adding functionality this component that you'd want to be available in both // dev and prod modes. return ; }, }); const RCTView = requireNativeComponent('RCTView', View, { nativeOnly: { nativeBackgroundAndroid: true, } }); if (__DEV__) { const viewConfig = UIManager.viewConfigs && UIManager.viewConfigs.RCTView || {}; for (const prop in viewConfig.nativeProps) { const viewAny: any = View; // Appease flow if (!viewAny.propTypes[prop] && !ReactNativeStyleAttributes[prop]) { throw new Error( 'View is missing propType for native prop `' + prop + '`' ); } } } let ViewToExport = RCTView; if (__DEV__) { ViewToExport = View; } else { Object.assign(RCTView, statics); } module.exports = ViewToExport;