private static void updateGlowSize(RecyclerView rv, EdgeEffectCompat topGlow) {
int width = rv.getMeasuredWidth();
int height = rv.getMeasuredHeight();
if (getClipToPadding(rv)) {
width -= rv.getPaddingLeft() - rv.getPaddingRight();
height -= rv.getPaddingTop() - rv.getPaddingBottom();
}
width = Math.max(0, width);
height = Math.max(0, height);
topGlow.setSize(width, height);
}
/**
* 绘制纵向 item 分割线
*
* @param canvas
* @param parent
*/
private void drawVertical(Canvas canvas, RecyclerView parent) {
final int left = parent.getPaddingLeft();
final int right = parent.getMeasuredWidth() - parent.getPaddingRight();
final int childSize = parent.getChildCount();
// linearLayoutManager.findFirstVisibleItemPosition();
for (int i = 0; i < childSize; i++) {
final View child = parent.getChildAt(i);
RecyclerView.LayoutParams layoutParams =
(RecyclerView.LayoutParams) child.getLayoutParams();
final int top = child.getBottom() + layoutParams.bottomMargin;
final int bottom = top + mItemSize;
canvas.drawRect(left, top, right, bottom, mPaint);
}
}
@Override
public void onDrawLoadMore(Canvas c, RecyclerView parent) {
super.onDrawLoadMore(c, parent);
mProgress = mProgress + 5;
if (mProgress == 100) {
mProgress = 0;
}
final int left = parent.getPaddingLeft();
final int right = parent.getMeasuredWidth() - parent.getPaddingRight();
final int childSize = parent.getChildCount();
final View child = parent.getChildAt(childSize - 1);
RecyclerView.LayoutParams layoutParams = (RecyclerView.LayoutParams) child.getLayoutParams();
final int top = child.getBottom() + layoutParams.bottomMargin;
final int bottom = top + getLoadMorePadding() / 2;
paint.setAntiAlias(true); // 抗锯齿
paint.setFlags(Paint.ANTI_ALIAS_FLAG); // 增强消除锯齿
paint.setColor(Color.GRAY); // 画笔为灰色
paint.setStrokeWidth(10); // 画笔宽度
paint.setStyle(Paint.Style.STROKE); // 中空
c.drawCircle(
(right - left) / 2 - mCircleOffset,
bottom,
mCircleSize,
paint); // 在中心为（(right - left)/2,bottom）的地方画个半径为mCircleSize的圆，
paint.setColor(Color.GREEN); // 设置画笔为绿色
oval.set(
(right - left) / 2 - mCircleOffset - mCircleSize,
bottom - mCircleSize,
(right - left) / 2 - mCircleOffset + mCircleSize,
bottom + mCircleSize); // 在Circle小于圈圈大小的地方画圆，这样也就保证了半径为mCircleSize
c.drawArc(
oval,
-90,
((float) mProgress / 100) * 360,
false,
paint); // 圆弧，第二个参数为：起始角度，第三个为跨的角度，第四个为true的时候是实心，false的时候为空心
paint.reset(); // 将画笔重置
paint.setStrokeWidth(3); // 再次设置画笔的宽度
paint.setTextSize(40); // 设置文字的大小
paint.setColor(Color.BLACK); // 设置画笔颜色
c.drawText(getLoadmoreString(), (right - left) / 2, bottom + 10, paint);
}
@Override
public void onScrollStateChanged(RecyclerView recyclerView, int newState) {
super.onScrollStateChanged(recyclerView, newState);
LinearLayoutManager linearLayoutManager =
(LinearLayoutManager) recyclerView.getLayoutManager();
if (mCenterPivot == 0) {
mCenterPivot = recyclerView.getLeft() + recyclerView.getRight();
}
if (!mAutoSet) {
synchronized (this) {
if (newState == RecyclerView.SCROLL_STATE_IDLE) {
View view = linearLayoutManager.findViewByPosition(mPosition);
mPosition = INITIAL_POSITION;
if (view == null) {
view = findCenterView(linearLayoutManager);
}
int viewCenter = (view.getLeft() + view.getRight()) / 2;
int viewWidth = view.getRight() - view.getLeft();
int scrollNeeded = viewCenter - mCenterPivot;
if (BuildConfig.DEBUG)
Log.d(
TAG,
"viewCentre = "
+ viewCenter
+ " viewWidth = "
+ viewWidth
+ " scrollNeeded = "
+ scrollNeeded
+ " recyclerViewWidth = "
+ recyclerView.getMeasuredWidth());
recyclerView.smoothScrollBy(scrollNeeded, 0);
mCenterHolderPosition = recyclerView.getChildLayoutPosition(view);
if (BuildConfig.DEBUG)
Log.d(
TAG,
"centerHolderPosition = " + mCenterHolderPosition + " mPosition = " + mPosition);
if (mScrollType == null) {
mScrollType = SwipeType.SWIPE;
}
onCenterItemSnap(
mCenterHolderPosition, recyclerView.getChildViewHolder(view), mScrollType);
mScrollType = null;
mAutoSet = true;
}
}
}
if (newState == RecyclerView.SCROLL_STATE_DRAGGING
|| newState == RecyclerView.SCROLL_STATE_SETTLING) {
mAutoSet = false;
}
}