View
The most fundamental component for building a UI, View
is a container that supports layout with flexbox, style, some touch handling, and accessibility controls. View
maps directly to the native view equivalent on whatever platform React Native is running on, whether that is a UIView
, <div>
, 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 boxes with color and a text component in a row with padding.
View
s are designed to be used withStyleSheet
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 in form of PressEvent.
Reference
Props
accessibilityActions
Accessibility actions allow an assistive technology to programmatically invoke the actions of a component. The accessibilityActions
property should contain a list of action objects. Each action object should contain the field name and label.
See the Accessibility guide for more information.
Type |
---|
array |
accessibilityElementsHidden
iOS
A value indicating whether the accessibility elements contained within this accessibility element are hidden. Default is false
.
See the Accessibility guide for more information.
Type |
---|
bool |
accessibilityHint
An accessibility hint helps users understand what will happen when they perform an action on the accessibility element when that result is not clear from the accessibility label.
Type |
---|
string |
accessibilityLanguage
iOS
A value indicating which language should be used by the screen reader when the user interacts with the element. It should follow the BCP 47 specification.
See the iOS accessibilityLanguage
doc for more information.
Type |
---|
string |
accessibilityIgnoresInvertColors
iOS
A value indicating this view should or should not be inverted when color inversion is turned on. A value of true
will tell the view to not be inverted even if color inversion is turned on.
See the Accessibility guide for more information.
Type |
---|
bool |
accessibilityLabel
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.
Type |
---|
string |
accessibilityLiveRegion
Android
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 for reference.
Type |
---|
enum('none', 'polite', 'assertive') |
accessibilityRole
accessibilityRole
communicates the purpose of a component to the user of an assistive technology.
accessibilityRole
can be one of the following:
'none'
- Used when the element has no role.'button'
- Used when the element should be treated as a button.'link'
- Used when the element should be treated as a link.'search'
- Used when the text field element should also be treated as a search field.'image'
- Used when the element should be treated as an image. Can be combined with button or link, for example.'keyboardkey'
- Used when the element acts as a keyboard key.'text'
- Used when the element should be treated as static text that cannot change.'adjustable'
- Used when an element can be "adjusted" (e.g. a slider).'imagebutton'
- Used when the element should be treated as a button and is also an image.'header'
- Used when an element acts as a header for a content section (e.g. the title of a navigation bar).'summary'
- Used when an element can be used to provide a quick summary of current conditions in the app when the app first launches.'alert'
- Used when an element contains important text to be presented to the user.'checkbox'
- Used when an element represents a checkbox which can be checked, unchecked, or have mixed checked state.'combobox'
- Used when an element represents a combo box, which allows the user to select among several choices.'menu'
- Used when the component is a menu of choices.'menubar'
- Used when a component is a container of multiple menus.'menuitem'
- Used to represent an item within a menu.'progressbar'
- Used to represent a component which indicates progress of a task.'radio'
- Used to represent a radio button.'radiogroup'
- Used to represent a group of radio buttons.'scrollbar'
- Used to represent a scroll bar.'spinbutton'
- Used to represent a button which opens a list of choices.'switch'
- Used to represent a switch which can be turned on and off.'tab'
- Used to represent a tab.'tablist'
- Used to represent a list of tabs.'timer'
- Used to represent a timer.'toolbar'
- Used to represent a tool bar (a container of action buttons or components).'grid'
- Used with ScrollView, VirtualizedList, FlatList, or SectionList to represent a grid. Adds the in/out of grid announcements to the android GridView.
Type |
---|
string |
accessibilityState
Describes the current state of a component to the user of an assistive technology.
See the Accessibility guide for more information.
Type |
---|
object: {disabled: bool, selected: bool, checked: bool or 'mixed', busy: bool, expanded: bool} |
accessibilityValue
Represents the current value of a component. It can be a textual description of a component's value, or for range-based components, such as sliders and progress bars, it contains range information (minimum, current, and maximum).
See the Accessibility guide for more information.
Type |
---|
object: {min: number, max: number, now: number, text: string} |
accessibilityViewIsModal
iOS
A value indicating whether VoiceOver should ignore the elements within views that are siblings of the receiver. Default is false
.
See the Accessibility guide for more information.
Type |
---|
bool |
accessible
When true
, indicates that the view is an accessibility element. By default, all the touchable elements are accessible.
aria-busy
Indicates an element is being modified and that assistive technologies may want to wait until the changes are complete before informing the user about the update.
Type | Default |
---|---|
boolean | false |
aria-checked
Indicates the state of a checkable element. This field can either take a boolean or the "mixed" string to represent mixed checkboxes.
Type | Default |
---|---|
boolean, 'mixed' | false |
aria-disabled
Indicates that the element is perceivable but disabled, so it is not editable or otherwise operable.
Type | Default |
---|---|
boolean | false |
aria-expanded
Indicates whether an expandable element is currently expanded or collapsed.
Type | Default |
---|---|
boolean | false |
aria-hidden
Indicates whether the accessibility elements contained within this accessibility element are hidden.
For example, in a window that contains sibling views A
and B
, setting aria-hidden
to true
on view B
causes VoiceOver to ignore the elements in the view B
.
Type | Default |
---|---|
boolean | false |
aria-label
Defines a string value that labels an interactive element.
Type |
---|
string |
aria-labelledby
Android
Identifies the element that labels the element it is applied to. The value of aria-labelledby
should match the nativeID
of the related element:
<View>
<Text nativeID="formLabel">Label for Input Field</Text>
<TextInput aria-label="input" aria-labelledby="formLabel" />
</View>
Type |
---|
string |
aria-live
Android
Indicates that an element will be updated, and describes the types of updates the user agents, assistive technologies, and user can expect from the live region.
- off 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.
Type | Default |
---|---|
enum('assertive' , 'off' , 'polite' ) | 'off' |
aria-modal
iOS
Boolean value indicating whether VoiceOver should ignore the elements within views that are siblings of the receiver. Has precedence over the accessibilityViewIsModal
prop.
Type | Default |
---|---|
boolean | false |
aria-selected
Indicates whether a selectable element is currently selected or not.
Type |
---|
boolean |
aria-valuemax
Represents the maximum value for range-based components, such as sliders and progress bars. Has precedence over the max
value in the accessibilityValue
prop.
Type |
---|
number |
aria-valuemin
Represents the minimum value for range-based components, such as sliders and progress bars. Has precedence over the min
value in the accessibilityValue
prop.
Type |
---|
number |
aria-valuenow
Represents the current value for range-based components, such as sliders and progress bars. Has precedence over the now
value in the accessibilityValue
prop.
Type |
---|
number |
aria-valuetext
Represents the textual description of the component. Has precedence over the text
value in the accessibilityValue
prop.
Type |
---|
string |
collapsable
Android
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.
Type |
---|
bool |
focusable
Android
Whether this View
should be focusable with a non-touch input device, eg. receive focus with a hardware keyboard.
Type |
---|
boolean |
hitSlop
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.
Type |
---|
object: {top: number, left: number, bottom: number, right: number} |
id
Used to locate this view from native classes. Has precedence over nativeID
prop.
This disables the 'layout-only view removal' optimization for this view!
Type |
---|
string |
importantForAccessibility
Android
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 for reference.
Type |
---|
enum('auto', 'yes', 'no', 'no-hide-descendants') |
nativeID
Used to locate this view from native classes.
This disables the 'layout-only view removal' optimization for this view!
Type |
---|
string |
needsOffscreenAlphaCompositing
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.
Type |
---|
bool |
nextFocusDown
Android
Designates the next view to receive focus when the user navigates down. See the Android documentation.
Type |
---|
number |
nextFocusForward
Android
Designates the next view to receive focus when the user navigates forward. See the Android documentation.
Type |
---|
number |
nextFocusLeft
Android
Designates the next view to receive focus when the user navigates left. See the Android documentation.
Type |
---|
number |
nextFocusRight
Android
Designates the next view to receive focus when the user navigates right. See the Android documentation.
Type |
---|
number |
nextFocusUp
Android
Designates the next view to receive focus when the user navigates up. See the Android documentation.
Type |
---|
number |
onAccessibilityAction
Invoked when the user performs the accessibility actions. The only argument to this function is an event containing the name of the action to perform.
See the Accessibility guide for more information.
Type |
---|
function |
onAccessibilityEscape
iOS
When accessible
is true
, the system will invoke this function when the user performs the escape gesture.
Type |
---|
function |
onAccessibilityTap
When accessible
is true, the system will try to invoke this function when the user performs accessibility tap gesture.
Type |
---|
function |
onLayout
Invoked on mount and on layout changes.
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.
Type |
---|
({nativeEvent: LayoutEvent}) => void |
onMagicTap
iOS
When accessible
is true
, the system will invoke this function when the user performs the magic tap gesture.
Type |
---|
function |