Android APIs
public final class

Display

extends Object
java.lang.Object
   ↳ android.view.Display

Class Overview

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 the following methods to query the application display area: getSize(Point), getRectSize(Rect) and getMetrics(DisplayMetrics).
  • The real display area specifies the part of the display that contains content including the system decorations. Even so, the real display area may be smaller than the physical size of the display if the window manager is emulating a smaller display using (adb shell am display-size). Use the following methods to query the real display area: getRealSize(Point), getRealMetrics(DisplayMetrics).

A logical display does not necessarily represent a particular physical display device such as the built-in screen or an external monitor. 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

Constants
int DEFAULT_DISPLAY The default Display id, which is the id of the built-in primary display assuming there is one.
int FLAG_PRESENTATION Display flag: Indicates that the display is a presentation display.
int FLAG_PRIVATE Display flag: Indicates that the display is private.
int FLAG_SECURE Display flag: Indicates that the display has a secure video output and supports compositing secure surfaces.
int FLAG_SUPPORTS_PROTECTED_BUFFERS Display flag: Indicates that the display supports compositing content that is stored in protected graphics buffers.
int STATE_DOZING Display state: The display is dozing in a low-power state; it may be showing system-provided content while the device is in a non-interactive state.
int STATE_OFF Display state: The display is off.
int STATE_ON Display state: The display is on.
int STATE_UNKNOWN Display state: The display state is unknown.
Public Methods
void getCurrentSizeRange(Point outSmallestSize, Point outLargestSize)
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.
int getDisplayId()
Gets the display id.
int getFlags()
Returns a combination of flags that describe the capabilities of the display.
int getHeight()
This method was deprecated in API level 13. Use getSize(Point) instead.
void getMetrics(DisplayMetrics outMetrics)
Gets display metrics that describe the size and density of this display.
String getName()
Gets the name of the display.
int getOrientation()
This method was deprecated in API level 8. use getRotation()
int getPixelFormat()
This method was deprecated in API level 17. This method is no longer supported. The result is always RGBA_8888.
void getRealMetrics(DisplayMetrics outMetrics)
Gets display metrics based on the real size of this display.
void getRealSize(Point outSize)
Gets the real size of the display without subtracting any window decor or applying any compatibility scale factors.
void getRectSize(Rect outSize)
Gets the size of the display as a rectangle, in pixels.
float getRefreshRate()
Gets the refresh rate of this display in frames per second.
int getRotation()
Returns the rotation of the screen from its "natural" orientation.
void getSize(Point outSize)
Gets the size of the display, in pixels.
int getState()
Gets the state of the display, such as whether it is on or off.
int getWidth()
This method was deprecated in API level 13. Use getSize(Point) instead.
boolean isValid()
Returns true if this display is still valid, false if the display has been removed.
String toString()
Returns a string containing a concise, human-readable description of this object.
[Expand]
Inherited Methods
From class java.lang.Object

Constants

public static final int DEFAULT_DISPLAY

Added in API level 1

The default Display id, which is the id of the built-in primary display assuming there is one.

Constant Value: 0 (0x00000000)

public static final int FLAG_PRESENTATION

Added in API level 19

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 HDMI or Wireless displays. Applications may automatically project their content to presentation displays to provide richer second screen experiences.

See Also
Constant Value: 8 (0x00000008)

public static final int FLAG_PRIVATE

Added in API level 19

Display flag: Indicates that the display is private. Only the application that owns the display can create windows on it.

See Also
Constant Value: 4 (0x00000004)

public static final int FLAG_SECURE

Added in API level 17

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 FLAG_SECURE window flag. Likewise, an application creates a SurfaceView with a secure surface by calling setSecure(boolean) 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.

See Also
Constant Value: 2 (0x00000002)

public static final int FLAG_SUPPORTS_PROTECTED_BUFFERS

Added in API level 17

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.

See Also
Constant Value: 1 (0x00000001)

public static final int STATE_DOZING

Added in API level 20

Display state: The display is dozing in a low-power state; it may be showing system-provided content while the device is in a non-interactive state.

Constant Value: 3 (0x00000003)

public static final int STATE_OFF

Added in API level 20

Display state: The display is off.

See Also
Constant Value: 1 (0x00000001)

public static final int STATE_ON

Added in API level 20

Display state: The display is on.

See Also
Constant Value: 2 (0x00000002)

public static final int STATE_UNKNOWN

Added in API level 20

Display state: The display state is unknown.

See Also
Constant Value: 0 (0x00000000)

Public Methods

public void getCurrentSizeRange (Point outSmallestSize, Point outLargestSize)

Added in API level 16

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
outSmallestSize 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 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.

public int getDisplayId ()

Added in API level 1

Gets the display id.

Each logical display has a unique id. The default display has id DEFAULT_DISPLAY.

public int getFlags ()

Added in API level 17

Returns a combination of flags that describe the capabilities of the display.

Returns
  • The display flags.

public int getHeight ()

Added in API level 1

This method was deprecated in API level 13.
Use getSize(Point) instead.

public void getMetrics (DisplayMetrics outMetrics)

Added in API level 1

Gets display metrics that describe the size and density of this display.

The size is adjusted based on the current rotation of the display.

The size returned by this method does not necessarily represent the actual raw size (native resolution) of the display. The returned size may be adjusted to exclude certain system decor elements that are always visible. It may also be scaled to provide compatibility with older applications that were originally designed for smaller displays.

Parameters
outMetrics A DisplayMetrics object to receive the metrics.

public String getName ()

Added in API level 17

Gets the name of the display.

Note that some displays may be renamed by the user.

Returns
  • The display's name.

public int getOrientation ()

Added in API level 1

This method was deprecated in API level 8.
use getRotation()

Returns
  • orientation of this display.

public int getPixelFormat ()

Added in API level 1

This method was deprecated in API level 17.
This method is no longer supported. The result is always RGBA_8888.

Gets the pixel format of the display.

Returns

public void getRealMetrics (DisplayMetrics outMetrics)

Added in API level 17

Gets display metrics based on the real size of this display.

The size is adjusted based on the current rotation of the display.

The real size may be smaller than the physical size of the screen when the window manager is emulating a smaller display (using adb shell am display-size).

Parameters
outMetrics A DisplayMetrics object to receive the metrics.

public void getRealSize (Point outSize)

Added in API level 17

Gets the real size of the display without subtracting any window decor or applying any compatibility scale factors.

The size is adjusted based on the current rotation of the display.

The real size may be smaller than the physical size of the screen when the window manager is emulating a smaller display (using adb shell am display-size).

Parameters
outSize Set to the real size of the display.

public void getRectSize (Rect outSize)

Added in API level 13

Gets the size of the display as a rectangle, in pixels.

Parameters
outSize A Rect object to receive the size information.
See Also

public float getRefreshRate ()

Added in API level 1

Gets the refresh rate of this display in frames per second.

public int getRotation ()

Added in API level 8

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.

public void getSize (Point outSize)

Added in API level 13

Gets the size of the display, in pixels.

Note that this value should not be used for computing layouts, since a device will typically have screen decoration (such as a status bar) along the edges of the display that reduce the amount of application space available from the size returned here. Layouts should instead use the window size.

The size is adjusted based on the current rotation of the display.

The size returned by this method does not necessarily represent the actual raw size (native resolution) of the display. The returned size may be adjusted to exclude certain system decoration elements that are always visible. It may also be scaled to provide compatibility with older applications that were originally designed for smaller displays.

Parameters
outSize A Point object to receive the size information.

public int getState ()

Added in API level 20

Gets the state of the display, such as whether it is on or off.

Returns

public int getWidth ()

Added in API level 1

This method was deprecated in API level 13.
Use getSize(Point) instead.

public boolean isValid ()

Added in API level 17

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.

Returns
  • True if the display is still valid.

public String toString ()

Added in API level 1

Returns a string containing a concise, human-readable description of this object. Subclasses are encouraged to override this method and provide an implementation that takes into account the object's type and data. The default implementation is equivalent to the following expression:

   getClass().getName() + '@' + Integer.toHexString(hashCode())

See Writing a useful toString method if you intend implementing your own toString method.

Returns
  • a printable representation of this object.