自定义View仿抖音视频加载BufferLineView

• 1. 自定义View仿抖音视频加载BufferLineView
• 2. 自定义视频选帧控件
• 3. 自定义View 视频截取控件

自定义动画线

public class BufferLineView extends View {
    public BufferLineView(Context context) {
        this(context, null);
    }

    public BufferLineView(Context context, @Nullable AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public BufferLineView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private int bgColor = Color.TRANSPARENT;
    private Paint mLinePaint;
    private int mWidth;
    private int mStartSpace = 200;
    private int mOffset = 0;
    private ValueAnimator valueAnimator;
    private boolean endFlag = false;

    private void init() {
        mLinePaint = new Paint();
        mLinePaint.setColor(bgColor);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        mWidth = Math.max(MeasureSpec.getSize(widthMeasureSpec), 1);
        int mHeight = MeasureSpec.getSize(heightMeasureSpec);
        mStartSpace = mWidth / 2;
        mOffset = mStartSpace / 20;
        mLinePaint.setStrokeWidth(mHeight);
    }

    public void startAnimate() {
        if (valueAnimator == null) {
            valueAnimator = new ValueAnimator();
            valueAnimator.setIntValues(mStartSpace, mOffset);
            valueAnimator.setDuration(800);
            valueAnimator.setInterpolator(new AccelerateDecelerateInterpolator());
            valueAnimator.setRepeatCount(ValueAnimator.INFINITE);

            valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
                @Override
                public void onAnimationUpdate(ValueAnimator animation) {
                    mStartSpace = (int) animation.getAnimatedValue();
                    if (endFlag && mStartSpace < mOffset + 10) {
                        valueAnimator.cancel();
                        return;
                    }
                    invalidate();
                }
            });

            valueAnimator.addListener(new AnimatorListenerAdapter() {
                @Override
                public void onAnimationEnd(Animator animation) {
                    // 隐藏线条
                    mLinePaint.setColor(bgColor);
                    invalidate();
                }
            });
        }
        if (valueAnimator.isRunning()) {
            return;
        }
        endFlag = false;
        valueAnimator.start();
    }

    public void endAnimate() {
        endFlag = true;
    }

    public void destroy() {
        endFlag = false;
        if (valueAnimator != null) {
            valueAnimator.removeAllUpdateListeners();
            valueAnimator.removeAllListeners();
            valueAnimator.cancel();
            valueAnimator = null;
        }
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        int alpha = (int) (mStartSpace * 2.0f / mWidth * 225);
        int statusColor = calculateStatusColor(alpha);
        mLinePaint.setColor(statusColor);
        canvas.drawLine(mStartSpace, 0, mWidth - mStartSpace, 0, mLinePaint);
    }

    public int calculateStatusColor(@IntRange(from = 0, to = 225) int alpha) {
        return Color.argb(alpha, 248, 248, 255);
    }
}