Detect app draw time

import android.util.Log;
import android.view.Choreographer;

/**
 * Created by sensetime on 18-4-25.
 */

public class SMFrameCallback implements Choreographer.FrameCallback {
    public static SMFrameCallback sInstance;
    private String TAG = "SMFrameCallback";
    public static final float deviceRefreshRateMs = 16.6f;
    public static long lastFrameTimeNanos = 0;//Nanoseconds
    public static long currentFrameTimeNanos = 0;

    public void start() {
        Choreographer.getInstance().postFrameCallback(SMFrameCallback.getInstance());
    }

    public static SMFrameCallback getInstance() {
        if (sInstance == null) {
            sInstance = new SMFrameCallback();
        }
        return sInstance;
    }

    @Override
    public void doFrame(long frameTimeNanos) {
        if (lastFrameTimeNanos == 0) {
            lastFrameTimeNanos = frameTimeNanos;
            Choreographer.getInstance().postFrameCallback(this);
            return;
        }
        currentFrameTimeNanos = frameTimeNanos;
        float value = (currentFrameTimeNanos - lastFrameTimeNanos) / 1000000.0f;
        final int skipFrameCount = skipFrameCount(lastFrameTimeNanos, currentFrameTimeNanos, deviceRefreshRateMs);
        Log.e(TAG, "Drawing time interval value=" + value + " frameTimeNanos=" + frameTimeNanos + " currentFrameTimeNanos=" + currentFrameTimeNanos + " skipFrameCount=" + skipFrameCount + "");
        lastFrameTimeNanos = currentFrameTimeNanos;
        Choreographer.getInstance().postFrameCallback(this);
    }

    /**
     * * Calculate how many frames to skip * @param start * @param end * @param devicefreshRate * @return
     */
    private int skipFrameCount(long start, long end, float devicefreshRate) {
        int count = 0;
        long diffNs = end - start;
        long diffMs = Math.round(diffNs / 1000000.0f);
        long dev = Math.round(devicefreshRate);
        if (diffMs > dev) {
            long skipCount = diffMs / dev;
            count = (int) skipCount;
        }
        return count;
    }
}

Reference: https://www.jianshu.com/p/777fe2f71039