Display
class Display
kotlin.Any | |
↳ | android.view.Display |
Provides information about the size and density of a logical display.
The display area is described in two different ways.
- The application display area specifies the part of the display that may contain an application window, excluding the system decorations. The application display area may be smaller than the real display area because the system subtracts the space needed for decor elements such as the status bar. Use
WindowMetrics#getBounds()
to query the application window bounds. - The real display area specifies the part of the display that is accessible to an application in the current system state. The real display area may be smaller than the physical size of the display in a few scenarios. Use
WindowManager#getCurrentWindowMetrics()
to identify the current size of the activity window. UI-related work, such as choosing UI layouts, should rely uponWindowMetrics#getBounds()
. SeegetRealSize
/getRealMetrics
for details.
A logical display does not necessarily represent a particular physical display device such as the internal display or an external display. The contents of a logical display may be presented on one or more physical displays according to the devices that are currently attached and whether mirroring has been enabled.
Summary
Nested classes | |
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Encapsulates the HDR capabilities of a given display. |
|
A mode supported by a given display. |
Constants | |
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static Int |
The default Display id, which is the id of the primary display assuming there is one. |
static Int |
Display flag: Indicates that the display is a presentation display. |
static Int |
Display flag: Indicates that the display is private. |
static Int |
Display flag: Indicates that the display has a round shape. |
static Int |
Display flag: Indicates that the display has a secure video output and supports compositing secure surfaces. |
static Int |
Display flag: Indicates that the display supports compositing content that is stored in protected graphics buffers. |
static Int |
Invalid display id. |
static Int |
Display state: The display is dozing in a low power state; it is still on but is optimized for showing system-provided content while the device is non-interactive. |
static Int |
Display state: The display is dozing in a suspended low power state; it is still on but the CPU is not updating it. |
static Int |
Display state: The display is off. |
static Int |
Display state: The display is on. |
static Int |
Display state: The display is in a suspended full power state; it is still on but the CPU is not updating it. |
static Int |
Display state: The display state is unknown. |
static Int |
Display state: The display is on and optimized for VR mode. |
Public methods | |
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Long |
Gets the app VSYNC offset, in nanoseconds. |
Unit |
getCurrentSizeRange(outSmallestSize: Point!, outLargestSize: Point!) Return the range of display sizes an application can expect to encounter under normal operation, as long as there is no physical change in screen size. |
DisplayCutout? |
Returns the |
DeviceProductInfo? |
Returns the product-specific information about the display or the directly connected device on the display chain. |
Int |
Gets the display id. |
Int |
getFlags() Returns a combination of flags that describe the capabilities of the display. |
Display.HdrCapabilities! |
Returns the current display mode's HDR capabilities. |
Float | |
Int | |
Unit |
getMetrics(outMetrics: DisplayMetrics!) Gets the size and density of this display. |
Display.Mode! |
getMode() Returns the active mode of the display. |
String! |
getName() Gets the name of the display. |
Int | |
OverlayProperties |
Returns the |
Int |
Gets the pixel format of the display. |
ColorSpace? |
Returns the preferred wide color space of the Display. |
Long |
This is how far in advance a buffer must be queued for presentation at a given time. |
Unit |
getRealMetrics(outMetrics: DisplayMetrics!) Gets the size of the largest region of the display accessible to an app in the current system state, without subtracting any window decor or applying scaling factors. |
Unit |
getRealSize(outSize: Point!) Gets the size of the largest region of the display accessible to an app in the current system state, without subtracting any window decor or applying scaling factors. |
Unit |
getRectSize(outSize: Rect!) Gets the size of the display as a rectangle, in pixels. |
Float |
Gets the refresh rate of this display in frames per second. |
Int |
Returns the rotation of the screen from its "natural" orientation. |
RoundedCorner? |
getRoundedCorner(position: Int) Returns the |
DisplayShape |
getShape() Returns the |
Unit |
Gets the size of the display in pixels. |
Int |
getState() Gets the state of the display, such as whether it is on or off. |
Array<Display.Mode!>! |
Gets the supported modes of this display, might include synthetic modes |
FloatArray! |
Get the supported refresh rates of this display in frames per second. |
Int |
getWidth() |
Boolean |
isHdr() Returns whether this display supports any HDR type. |
Boolean | |
Boolean |
Returns true if the connected display can be switched into a mode with minimal post processing. |
Boolean |
isValid() Returns true if this display is still valid, false if the display has been removed. |
Boolean |
Returns whether this display can be used to display wide color gamut content. |
Unit |
registerHdrSdrRatioChangedListener(executor: Executor, listener: Consumer<Display!>) Registers a listener that will be invoked whenever the display's hdr/sdr ratio has changed. |
String |
toString() |
Unit |
unregisterHdrSdrRatioChangedListener(listener: Consumer<Display!>) |
Constants
DEFAULT_DISPLAY
static val DEFAULT_DISPLAY: Int
The default Display id, which is the id of the primary display assuming there is one.
Value: 0
FLAG_PRESENTATION
static val FLAG_PRESENTATION: Int
Display flag: Indicates that the display is a presentation display.
This flag identifies secondary displays that are suitable for use as presentation displays such as external or wireless displays. Applications may automatically project their content to presentation displays to provide richer second screen experiences.
Value: 8
See Also
FLAG_PRIVATE
static val FLAG_PRIVATE: Int
Display flag: Indicates that the display is private. Only the application that owns the display and apps that are already on the display can create windows on it.
Value: 4
See Also
FLAG_ROUND
static val FLAG_ROUND: Int
Display flag: Indicates that the display has a round shape.
This flag identifies displays that are circular, elliptical or otherwise do not permit the user to see all the way to the logical corners of the display.
Value: 16
See Also
FLAG_SECURE
static val FLAG_SECURE: Int
Display flag: Indicates that the display has a secure video output and supports compositing secure surfaces.
If this flag is set then the display device has a secure video output and is capable of showing secure surfaces. It may also be capable of showing protected buffers
.
If this flag is not set then the display device may not have a secure video output; the user may see a blank region on the screen instead of the contents of secure surfaces or protected buffers.
Secure surfaces are used to prevent content rendered into those surfaces by applications from appearing in screenshots or from being viewed on non-secure displays. Protected buffers are used by secure video decoders for a similar purpose.
An application creates a window with a secure surface by specifying the WindowManager.LayoutParams#FLAG_SECURE
window flag. Likewise, an application creates a SurfaceView
with a secure surface by calling SurfaceView#setSecure
before attaching the secure view to its containing window.
An application can use the absence of this flag as a hint that it should not create secure surfaces or protected buffers on this display because the content may not be visible. For example, if the flag is not set then the application may choose not to show content on this display, show an informative error message, select an alternate content stream or adopt a different strategy for decoding content that does not rely on secure surfaces or protected buffers.
Value: 2
See Also
FLAG_SUPPORTS_PROTECTED_BUFFERS
static val FLAG_SUPPORTS_PROTECTED_BUFFERS: Int
Display flag: Indicates that the display supports compositing content that is stored in protected graphics buffers.
If this flag is set then the display device supports compositing protected buffers.
If this flag is not set then the display device may not support compositing protected buffers; the user may see a blank region on the screen instead of the protected content.
Secure (DRM) video decoders may allocate protected graphics buffers to request that a hardware-protected path be provided between the video decoder and the external display sink. If a hardware-protected path is not available, then content stored in protected graphics buffers may not be composited.
An application can use the absence of this flag as a hint that it should not use protected buffers for this display because the content may not be visible. For example, if the flag is not set then the application may choose not to show content on this display, show an informative error message, select an alternate content stream or adopt a different strategy for decoding content that does not rely on protected buffers.
Value: 1
See Also
STATE_DOZE
static val STATE_DOZE: Int
Display state: The display is dozing in a low power state; it is still on but is optimized for showing system-provided content while the device is non-interactive.
Value: 3
STATE_DOZE_SUSPEND
static val STATE_DOZE_SUSPEND: Int
Display state: The display is dozing in a suspended low power state; it is still on but the CPU is not updating it. This may be used in one of two ways: to show static system-provided content while the device is non-interactive, or to allow a "Sidekick" compute resource to update the display. For this reason, the CPU must not control the display in this mode.
Value: 4
STATE_OFF
static val STATE_OFF: Int
Display state: The display is off.
Value: 1
See Also
STATE_ON
static val STATE_ON: Int
Display state: The display is on.
Value: 2
See Also
STATE_ON_SUSPEND
static val STATE_ON_SUSPEND: Int
Display state: The display is in a suspended full power state; it is still on but the CPU is not updating it. This may be used in one of two ways: to show static system-provided content while the device is non-interactive, or to allow a "Sidekick" compute resource to update the display. For this reason, the CPU must not control the display in this mode.
Value: 6
STATE_UNKNOWN
static val STATE_UNKNOWN: Int
Display state: The display state is unknown.
Value: 0
See Also
STATE_VR
static val STATE_VR: Int
Display state: The display is on and optimized for VR mode.
Value: 5
Public methods
getAppVsyncOffsetNanos
fun getAppVsyncOffsetNanos(): Long
Gets the app VSYNC offset, in nanoseconds. This is a positive value indicating the phase offset of the VSYNC events provided by Choreographer relative to the display refresh. For example, if Choreographer reports that the refresh occurred at time N, it actually occurred at (N - appVsyncOffset).
Apps generally do not need to be aware of this. It's only useful for fine-grained A/V synchronization.
getCurrentSizeRange
fun getCurrentSizeRange(
outSmallestSize: Point!,
outLargestSize: Point!
): Unit
Return the range of display sizes an application can expect to encounter under normal operation, as long as there is no physical change in screen size. This is basically the sizes you will see as the orientation changes, taking into account whatever screen decoration there is in each rotation. For example, the status bar is always at the top of the screen, so it will reduce the height both in landscape and portrait, and the smallest height returned here will be the smaller of the two. This is intended for applications to get an idea of the range of sizes they will encounter while going through device rotations, to provide a stable UI through rotation. The sizes here take into account all standard system decorations that reduce the size actually available to the application: the status bar, navigation bar, system bar, etc. It does not take into account more transient elements like an IME soft keyboard.
Parameters | |
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outSmallestSize |
Point!: Filled in with the smallest width and height that the application will encounter, in pixels (not dp units). The x (width) dimension here directly corresponds to Configuration.smallestScreenWidthDp , except the value here is in raw screen pixels rather than dp units. Your application may of course still get smaller space yet if, for example, a soft keyboard is being displayed. |
outLargestSize |
Point!: Filled in with the largest width and height that the application will encounter, in pixels (not dp units). Your application may of course still get larger space than this if, for example, screen decorations like the status bar are being hidden. |
getCutout
fun getCutout(): DisplayCutout?
Returns the DisplayCutout
, or null
if there is none.
See Also
getDeviceProductInfo
fun getDeviceProductInfo(): DeviceProductInfo?
Returns the product-specific information about the display or the directly connected device on the display chain. For example, if the display is transitively connected, this field may contain product information about the intermediate device. Returns null
if product information is not available.
getDisplayId
fun getDisplayId(): Int
Gets the display id.
Each logical display has a unique id. The default display has id DEFAULT_DISPLAY
.
getFlags
fun getFlags(): Int
Returns a combination of flags that describe the capabilities of the display.
Return | |
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Int |
The display flags. |
getHdrCapabilities
fun getHdrCapabilities(): Display.HdrCapabilities!
Returns the current display mode's HDR capabilities.
See Also
getHdrSdrRatio
fun getHdrSdrRatio(): Float
Return | |
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Float |
The current hdr/sdr ratio expressed as the ratio of targetHdrPeakBrightnessInNits / targetSdrWhitePointInNits. If isHdrSdrRatioAvailable() is false, this always returns 1.0f. |
getMetrics
fungetMetrics(outMetrics: DisplayMetrics!): Unit
Deprecated: Use WindowMetrics#getBounds()
to get the dimensions of the application window. Use WindowMetrics#getDensity()
to get the density of the application window.
Gets the size and density of this display.
The size returned does not necessarily represent the actual size (native resolution) of the display. The returned size might be adjusted to exclude certain system decor elements that are always visible, or the size might be scaled to provide compatibility with older applications that were originally designed for smaller displays.
The returned size can also be different depending on the WindowManager associated with the display:
- If metrics are requested from an activity (either using a WindowManager accessed by
getWindowManager()
orgetSystemService(Context.WINDOW_SERVICE)
), the returned metrics provide the size of the current app window. As a result, in multi-window mode, the returned size can be smaller than the size of the device screen. - If metrics are requested from a non-activity context (for example, the application context, where the WindowManager is accessed by
getApplicationContext().getSystemService(Context.WINDOW_SERVICE)
), the returned size can vary depending on API level:- API level 29 and below — The returned metrics provide the size of the entire display (based on current rotation) minus system decoration areas.
- API level 30 and above — The returned metrics provide the size of the top running activity in the current process. If the current process has no running activities, the metrics provide the size of the default display of the device, including system decoration areas.
Parameters | |
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outMetrics |
DisplayMetrics!: A DisplayMetrics object which receives the display metrics. |
getName
fun getName(): String!
Gets the name of the display.
Note that some displays may be renamed by the user.
Return | |
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String! |
The display's name. |
getOrientation
fungetOrientation(): Int
Deprecated: use getRotation
Return | |
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Int |
orientation of this display. Value is android.view.Surface#ROTATION_0 , android.view.Surface#ROTATION_90 , android.view.Surface#ROTATION_180 , or android.view.Surface#ROTATION_270 |
getOverlaySupport
fun getOverlaySupport(): OverlayProperties
Returns the OverlayProperties
of the display.
Return | |
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OverlayProperties |
This value cannot be null . |
getPixelFormat
fungetPixelFormat(): Int
Deprecated: This method is no longer supported. The result is always PixelFormat#RGBA_8888
.
Gets the pixel format of the display.
Return | |
---|---|
Int |
One of the constants defined in android.graphics.PixelFormat . |
getPreferredWideGamutColorSpace
fun getPreferredWideGamutColorSpace(): ColorSpace?
Returns the preferred wide color space of the Display. The returned wide gamut color space is based on hardware capability and is preferred by the composition pipeline. Returns null if the display doesn't support wide color gamut. Display#isWideColorGamut()
.
getPresentationDeadlineNanos
fun getPresentationDeadlineNanos(): Long
This is how far in advance a buffer must be queued for presentation at a given time. If you want a buffer to appear on the screen at time N, you must submit the buffer before (N - presentationDeadline).
The desired presentation time for GLES rendering may be set with android.opengl.EGLExt#eglPresentationTimeANDROID
. For video decoding, use android.media.MediaCodec#releaseOutputBuffer(int, long)
. Times are expressed in nanoseconds, using the system monotonic clock (System#nanoTime
).
getRealMetrics
fungetRealMetrics(outMetrics: DisplayMetrics!): Unit
Deprecated: Use WindowManager#getCurrentWindowMetrics()
to identify the current size of the activity window. UI-related work, such as choosing UI layouts, should rely upon WindowMetrics#getBounds()
. Use Configuration#densityDpi
to get the current density.
Gets the size of the largest region of the display accessible to an app in the current system state, without subtracting any window decor or applying scaling factors.
The size is adjusted based on the current rotation of the display.
The returned size will fall into one of these scenarios:- The device has no partitions on the display. The returned value is the largest region of the display accessible to an app in the current system state, regardless of windowing mode.
- The device divides a single display into multiple partitions. An application is restricted to a portion of the display. This is common in devices where the display changes size, such as foldables or large screens. The returned size will match the portion of the display the application is restricted to.
- The window manager is emulating a different display size, using
adb shell wm size
. The returned size will match the emulated display size.
The returned value is unsuitable to use when sizing and placing UI elements, since it does not reflect the application window size in any of these scenarios. WindowManager#getCurrentWindowMetrics()
is an alternative that returns the size of the current application window, even if the window is on a device with a partitioned display. This helps prevent UI bugs where UI elements are misaligned or placed beyond the bounds of the window.
WindowManager#getCurrentWindowMetrics()
reports the fullscreen window is half of the screen in size, and each split screen window is a quarter of the screen in size. On the other hand, getRealMetrics
reports half of the screen size for all windows, since the application windows are all restricted to their respective partitions.
Parameters | |
---|---|
outMetrics |
DisplayMetrics!: A DisplayMetrics object to receive the metrics. |
getRealSize
fungetRealSize(outSize: Point!): Unit
Deprecated: Use WindowManager#getCurrentWindowMetrics()
to identify the current size of the activity window. UI-related work, such as choosing UI layouts, should rely upon WindowMetrics#getBounds()
.
Gets the size of the largest region of the display accessible to an app in the current system state, without subtracting any window decor or applying scaling factors.
The size is adjusted based on the current rotation of the display.
The returned size will fall into one of these scenarios:- The device has no partitions on the display. The returned value is the largest region of the display accessible to an app in the current system state, regardless of windowing mode.
- The device divides a single display into multiple partitions. An application is restricted to a portion of the display. This is common in devices where the display changes size, such as foldables or large screens. The returned size will match the portion of the display the application is restricted to.
- The window manager is emulating a different display size, using
adb shell wm size
. The returned size will match the emulated display size.
The returned value is unsuitable to use when sizing and placing UI elements, since it does not reflect the application window size in any of these scenarios. WindowManager#getCurrentWindowMetrics()
is an alternative that returns the size of the current application window, even if the window is on a device with a partitioned display. This helps prevent UI bugs where UI elements are misaligned or placed beyond the bounds of the window.
WindowManager#getCurrentWindowMetrics()
reports the fullscreen window is half of the screen in size, and each split screen window is a quarter of the screen in size. On the other hand, getRealSize
reports half of the screen size for all windows, since the application windows are all restricted to their respective partitions.
Parameters | |
---|---|
outSize |
Point!: Set to the real size of the display. |
getRectSize
fungetRectSize(outSize: Rect!): Unit
Deprecated: Use WindowMetrics#getBounds()
to get the dimensions of the application window.
Gets the size of the display as a rectangle, in pixels.
Parameters | |
---|---|
outSize |
Rect!: A Rect object to receive the size information. |
getRefreshRate
fun getRefreshRate(): Float
Gets the refresh rate of this display in frames per second.
getRotation
fun getRotation(): Int
Returns the rotation of the screen from its "natural" orientation. The returned value may be Surface.ROTATION_0
(no rotation), Surface.ROTATION_90
, Surface.ROTATION_180
, or Surface.ROTATION_270
. For example, if a device has a naturally tall screen, and the user has turned it on its side to go into a landscape orientation, the value returned here may be either Surface.ROTATION_90
or Surface.ROTATION_270
depending on the direction it was turned. The angle is the rotation of the drawn graphics on the screen, which is the opposite direction of the physical rotation of the device. For example, if the device is rotated 90 degrees counter-clockwise, to compensate rendering will be rotated by 90 degrees clockwise and thus the returned value here will be Surface.ROTATION_90
. This rotation value will match the results of getMetrics
: this means that the rotation value will correspond to the activity if accessed through the activity.
Return | |
---|---|
Int |
Value is android.view.Surface#ROTATION_0 , android.view.Surface#ROTATION_90 , android.view.Surface#ROTATION_180 , or android.view.Surface#ROTATION_270 |
getRoundedCorner
fun getRoundedCorner(position: Int): RoundedCorner?
Returns the RoundedCorner
of the given position if there is one.
Parameters | |
---|---|
position |
Int: the position of the rounded corner on the display. Value is android.view.RoundedCorner#POSITION_TOP_LEFT , android.view.RoundedCorner#POSITION_TOP_RIGHT , android.view.RoundedCorner#POSITION_BOTTOM_RIGHT , or android.view.RoundedCorner#POSITION_BOTTOM_LEFT |
Return | |
---|---|
RoundedCorner? |
the rounded corner of the given position. Returns null if there is none. |
getShape
fun getShape(): DisplayShape
Returns the DisplayShape
which is based on display coordinates. To get the DisplayShape
based on the window frame, use WindowInsets#getDisplayShape()
instead.
Return | |
---|---|
DisplayShape |
This value cannot be null . |
See Also
getSize
fungetSize(outSize: Point!): Unit
Deprecated: Use WindowMetrics
instead. Obtain a WindowMetrics
instance by calling WindowManager#getCurrentWindowMetrics()
, then call WindowMetrics#getBounds()
to get the dimensions of the application window.
Gets the size of the display in pixels.
The return value does not necessarily represent the actual size (native resolution) of the display. The returned size might be adjusted to exclude certain system decor elements that are always visible, or the size might be scaled to provide compatibility with older applications that were originally designed for smaller displays.
The returned size can also be different depending on the WindowManager bound to the display:
- If size is requested from an activity (either using a WindowManager accessed by
getWindowManager()
orgetSystemService(Context.WINDOW_SERVICE)
), the size of the current app window is returned. As a result, in multi-window mode, the returned size can be smaller than the size of the device screen. The returned window size can vary depending on API level:- API level 35 and above, the window size will be returned.
- API level 34 and below, the window size minus system decoration areas and display cutout is returned.
- If size is requested from a non-activity context (for example, the application context, where the WindowManager is accessed by
getApplicationContext().getSystemService(Context.WINDOW_SERVICE)
), the returned size can vary depending on API level:- API level 29 and below — The size of the entire display (based on current rotation) minus system decoration areas is returned.
- API level 30 and above — The size of the top running activity in the current process is returned, system decoration areas exclusion follows the behavior defined above, based on the caller's API level. If the current process has no running activities, the size of the device default display, including system decoration areas, is returned.
For layout purposes, apps should make a request from an activity context to obtain the size of the display area available for app content.
Parameters | |
---|---|
outSize |
Point!: A Point object which receives the display size information. |
getState
fun getState(): Int
Gets the state of the display, such as whether it is on or off.
Return | |
---|---|
Int |
The state of the display: one of STATE_OFF , STATE_ON , STATE_DOZE , STATE_DOZE_SUSPEND , STATE_ON_SUSPEND , or STATE_UNKNOWN . |
getSupportedModes
fun getSupportedModes(): Array<Display.Mode!>!
Gets the supported modes of this display, might include synthetic modes
getSupportedRefreshRates
fungetSupportedRefreshRates(): FloatArray!
Deprecated: use getSupportedModes()
instead
Get the supported refresh rates of this display in frames per second.
This method only returns refresh rates for the display's default modes. For more options, use getSupportedModes()
.
isHdr
fun isHdr(): Boolean
Returns whether this display supports any HDR type.
isHdrSdrRatioAvailable
fun isHdrSdrRatioAvailable(): Boolean
Return | |
---|---|
Boolean |
Whether the display supports reporting an hdr/sdr ratio. If this is false, getHdrSdrRatio() will always be 1.0f |
isMinimalPostProcessingSupported
fun isMinimalPostProcessingSupported(): Boolean
Returns true if the connected display can be switched into a mode with minimal post processing.
If the Display sink is connected via HDMI, this method will return true if the display supports either Auto Low Latency Mode or Game Content Type.
If the Display sink has an internal connection or uses some other protocol than HDMI, this method will return true if the sink can be switched into an implementation-defined low latency image processing mode.
The ability to switch to a mode with minimal post processing may be disabled by a user setting in the system settings menu. In that case, this method returns false.
isValid
fun isValid(): Boolean
Returns true if this display is still valid, false if the display has been removed. If the display is invalid, then the methods of this class will continue to report the most recently observed display information. However, it is unwise (and rather fruitless) to continue using a Display
object after the display's demise. It's possible for a display that was previously invalid to become valid again if a display with the same id is reconnected.
Return | |
---|---|
Boolean |
True if the display is still valid. |
isWideColorGamut
fun isWideColorGamut(): Boolean
Returns whether this display can be used to display wide color gamut content. This does not necessarily mean the device itself can render wide color gamut content. To ensure wide color gamut content can be produced, refer to Configuration#isScreenWideColorGamut()
.
registerHdrSdrRatioChangedListener
fun registerHdrSdrRatioChangedListener(
executor: Executor,
listener: Consumer<Display!>
): Unit
Registers a listener that will be invoked whenever the display's hdr/sdr ratio has changed. After receiving the callback on the specified Executor, call getHdrSdrRatio()
to get the updated value. If isHdrSdrRatioAvailable()
is false, then an IllegalStateException will be thrown
Parameters | |
---|---|
executor |
Executor: The executor to invoke the listener on This value cannot be null . |
listener |
Consumer<Display!>: The listener to invoke when the HDR/SDR ratio changes This value cannot be null . |
Exceptions | |
---|---|
java.lang.IllegalStateException |
if isHdrSdrRatioAvailable() is false |
toString
fun toString(): String
Return | |
---|---|
String |
a string representation of the object. |
unregisterHdrSdrRatioChangedListener
fun unregisterHdrSdrRatioChangedListener(listener: Consumer<Display!>): Unit
Parameters | |
---|---|
listener |
Consumer<Display!>: The previously registered hdr/sdr ratio listener to remove. This value cannot be null . |