function showMenuWindow(view) {
  let popMenuWindow = ui.inflateXml(
    view.getContext(),
    `
    <column>
    <button id="btn1" text="btn1" />
    </column>
    `,
    null
  );
  let mPopWindow = new PopupWindow(popMenuWindow, ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT, true);
  mPopWindow.setOutsideTouchable(true);
  mPopWindow.showAsDropDown(view);
}
module.exports = showMenuWindow;

<column>
  <androidx.recyclerview.widget.RecyclerView id="recyclerView" padding="16" layout_width="match_parent" layout_height="match_parent">
  </androidx.recyclerview.widget.RecyclerView>
  <android.view.View id='arrow' ></android.view.View>
</column>

function showMenuWindow(view) {
  let popMenuWindow = ui.inflateXml(
    ...
  );
  setPopMenuRecyclerViewAdapter(popMenuWindow.recyclerView, []);
  ...
}

  menus: [
    {
      name: "復(fù)制",
      handle: () => {
        console.log("復(fù)制");
      },
    },
    {
      name: "分享",
      handle: () => {
        console.log("分享");
      },
    },
  ],

let definedClass = false;
const PopMenuRecyclerViewViewHolder = require("./PopMenuRecyclerViewViewHolder");
const PopMenuRecyclerViewAdapter = require("./PopMenuRecyclerViewAdapter");
const showMenuWindow = require("../showMenuWindow.js");
module.exports = async function (recyclerView, items) {
  if (!definedClass) {
    await $java.defineClass(PopMenuRecyclerViewViewHolder);
    await $java.defineClass(PopMenuRecyclerViewAdapter);
    definedClass = true;
  }
  var adapter = new PopMenuRecyclerViewAdapter(items);
  adapter.setLongClick(showMenuWindow);
  recyclerView.setAdapter(adapter);
};

bind(item) {
  this.itemView.attr("text", item);
  this.item = item;
}

const layoutManager = new androidx.recyclerview.widget.GridLayoutManager(this, 5);
grid.setLayoutManager(layoutManager);

bind(item) {
  this.itemView.attr("text", item.name);
  this.item = item;
}

<column>
  <androidx.recyclerview.widget.RecyclerView id="recyclerView" padding="16" layout_width="match_parent" layout_height="match_parent">
  </androidx.recyclerview.widget.RecyclerView>
  <android.view.View id='arrow' ></android.view.View>
</column>

arrowView.setForeground(drawable);

class TriangleDrawable extends android.graphics.drawable.Drawable {}

draw(canvas) {
  canvas.drawPath(this.path, paint);
}

view.getTop()

popWindow.getContentView().measure(View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED);
let popupWindowHeight = popWindow.getContentView().getMeasuredHeight()

  if (longClickedViewTop - popupWindowHeight < 0) {
    // 上面放不下了, 菜單在下面出現(xiàn), 箭頭指向上方
    return "up";
  } else {
    return "down";
  }

let arrowView = popMenuWindow.findView("arrow");
popMenuWindow.findView("root").removeView(arrowView);
popMenuWindow.findView("root").addView(arrowView, 0);

const layoutManager = new GridLayoutManager(view.getContext(), Math.min(popMenus.length, 5));

    let offset = popMenuCalculateOffset(view, mPopWindow, arrowDirection);
    if (arrowDirection == "down") {
      console.log("箭頭朝下");
      mPopWindow.showAsDropDown(view, offset.x, offset.y);
    }

module.exports = function popMenuCalculateOffset(longClickedView, popWindow, arrowDirection) {
  let contentView = popWindow.getContentView();
  let width = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
  let height = View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED);
  contentView.measure(width, height);
  popWindow.setBackgroundDrawable(new ColorDrawable(0));
  let contentViewHeight = contentView.getMeasuredHeight();
  let longClickedViewHeight = longClickedView.getHeight();
  console.log("contentViewHeight = " + contentViewHeight);
  if (arrowDirection == "down") {
    let y = contentViewHeight + longClickedViewHeight;
    return { x: 0, y: -y };
  } else {
    return { x: 0, y: 0 };
  }
};

    let offset = popMenuCalculateOffset(view, mPopWindow, arrowDirection);
    if (arrowDirection == "down") {
      console.log("箭頭朝下");
      mPopWindow.showAsDropDown(view, offset.x, offset.y);
    } else {
      let arrowView = popMenuWindow.findView("arrow");
      popMenuWindow.findView("root").removeView(arrowView);
      popMenuWindow.findView("root").addView(arrowView, 0);
      mPopWindow.showAsDropDown(view, offset.x, offset.y);
    }

class TriangleDrawable extends android.graphics.drawable.Drawable {}

class TriangleDrawable extends android.graphics.drawable.Drawable {
  setHeight(height) {
    this.height = height;
  }
  setWidth(width) {
    this.width = width;
  }
  setDirection(direction) {
    this.direction = direction;
  }
  setColor(color) {
    this.color = Color.parse(color).value;
  }
  setLongClickedViewWidth(longClickedViewWidth) {
    this.longClickedViewWidth = longClickedViewWidth;
  }
  draw(canvas) {
    trianglePath.reset();
    if (this.direction == "down") {
      console.log("down");
      trianglePath.moveTo(this.width / 2, this.height);
      trianglePath.lineTo(this.width / 2 - this.height / 2, 0);
      trianglePath.lineTo(this.width / 2 + this.height / 2, 0);
    } else {
      trianglePath.moveTo(this.width / 2, 0);
      trianglePath.lineTo(this.width / 2 - this.height / 2, this.height);
      trianglePath.lineTo(this.width / 2 + this.height / 2, this.height);
    }
    trianglePath.close();
    canvas.drawPath(trianglePath, paint);
  }
}
module.exports = TriangleDrawable;

await setArrowForeground(arrow, arrowDirection, view);
mPopWindow.showAsDropDown(view, offset.x, offset.y);

  arrow.getViewTreeObserver().addOnPreDrawListener(
    new android.view.ViewTreeObserver.OnPreDrawListener({
      onPreDraw: function () {
        arrow.getViewTreeObserver().removeOnPreDrawListener(this);
        let arrowHeight = arrow.getHeight();
        let arrowWidth = arrow.getWidth();
        triangleDrawable.setWidth(arrowWidth);
        triangleDrawable.setHeight(arrowHeight);
        arrow.setForeground(triangleDrawable);
        return true;
      },
    })
  );

<card cardCornerRadius="8dp" w='wrap_content'>
...
</card>

onCreateViewHolder(parent) {
  let testRecyclerViewViewHolder = new PopMenuRecyclerViewViewHolder(ui.inflateXml(parent.getContext(), holderXml, parent));
  testRecyclerViewViewHolder.itemView.setOnClickListener(() => {
    let item = this.data[testRecyclerViewViewHolder.getAdapterPosition()];
    item.handle();
    return true;
  });
  return testRecyclerViewViewHolder;
}