Display

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

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.

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

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.

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.

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.

Display state: The display is dozing in a suspended low power state; it is still on but is optimized for showing static system-provided content while the device is non-interactive. This mode may be used to conserve even more power by allowing the hardware to stop applying frame buffer updates from the graphics subsystem or to take over the display and manage it autonomously to implement low power always-on display functionality.

Display state: The display is off.

Display state: The display is on.

Display state: The display state is unknown.

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.

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.

Gets the display id.

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

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

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.

Gets the name of the display.

Note that some displays may be renamed by the user.

Gets the pixel format of the display.

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 eglPresentationTimeANDROID(EGLDisplay, EGLSurface, long). For video decoding, use releaseOutputBuffer(int, long). Times are expressed in nanoseconds, using the system monotonic clock (nanoTime()).

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).

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).

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

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

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.

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.

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

Get the supported refresh rates of this display in frames per second.

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 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.