Choreographer.FrameCallback
public
static
interface
Choreographer.FrameCallback
| android.view.Choreographer.FrameCallback |
Implement this interface to receive a callback when a new display frame is
being rendered. The callback is invoked on the Looper thread to
which the Choreographer is attached.
Summary
Public methods | |
|---|---|
abstract
void
|
doFrame(long frameTimeNanos)
Called when a new display frame is being rendered. |
Public methods
doFrame
public abstract void doFrame (long frameTimeNanos)
Called when a new display frame is being rendered.
This method provides the time in nanoseconds when the frame started being rendered.
The frame time provides a stable time base for synchronizing animations
and drawing. It should be used instead of SystemClock.uptimeMillis()
or System.nanoTime() for animations and drawing in the UI. Using the frame
time helps to reduce inter-frame jitter because the frame time is fixed at the time
the frame was scheduled to start, regardless of when the animations or drawing
callback actually runs. All callbacks that run as part of rendering a frame will
observe the same frame time so using the frame time also helps to synchronize effects
that are performed by different callbacks.
Please note that the framework already takes care to process animations and drawing using the frame time as a stable time base. Most applications should not need to use the frame time information directly.
| Parameters | |
|---|---|
frameTimeNanos |
long: The time in nanoseconds when the frame started being rendered,
in the System.nanoTime() timebase. Divide this value by 1000000
to convert it to the SystemClock.uptimeMillis() time base. |