弹窗类：

 public class ButtonPopupWindow extends PopupWindow {

    private Button cancelBtn;  //弹窗取消按钮
    private View menuview;
    private LinearLayout llItemContainer;
    private RelativeLayout rlRoot;
    private Button[] btnItems;

    public ButtonPopupWindow(Activity context, int itemNum) {
        super(context);
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        menuview = inflater.inflate(R.layout.bottom_popup_window, null);
        findUIControls();
        init();
        btnItems = new Button[itemNum];
        for (int i = 0; i < btnItems.length; i++) {
            Button btn = new Button(context);
            btn.setBackgroundColor(Color.WHITE);
            btn.setTextColor(Color.BLACK);
            btn.setTextSize(16);
            LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
                    ViewGroup.LayoutParams.MATCH_PARENT,
                    ViewGroup.LayoutParams.WRAP_CONTENT);
            layoutParams.topMargin = ((int) TypedValue.applyDimension([TypedValue.COMPLEX_UNIT_DIP], 2,
                    context.getResources().getDisplayMetrics()));
            btn.setLayoutParams(layoutParams);
            llItemContainer.addView(btn);
            btnItems[i] = btn;
        }
    }

    private void findUIControls() {
        cancelBtn = menuview.findViewById(R.id.item_popupwindows_cancel); //取消按钮
        llItemContainer = menuview.findViewById(R.id.ll_item_container);
        rlRoot = menuview.findViewById(R.id.rl_root);
    }

    private void init() {
        /*
         * 取消按钮销毁事件
         */
        cancelBtn.setOnClickListener(view -> dismiss());
        //设置SelectPicPopupWindow的View
        this.setContentView(menuview);
        //设置SelectPicPopupWindow**弹出窗体的宽
        this.setWidth(ViewGroup.LayoutParams.MATCH_PARENT);
        //设置SelectPicPopupWindow弹出窗体的高
        //修改高度显示，解决被手机底部虚拟键挡住的问题
        this.setHeight(ViewGroup.LayoutParams.MATCH_PARENT);
        //设置SelectPicPopupWindow弹出窗体可点击
        this.setFocusable(true);
        //设置SelectPicPopupWindow弹出窗体动画效果
        //this.setAnimationStyle(R.style);
        //实例化一个ColorDrawable颜色为半透明
        ColorDrawable dw = new ColorDrawable(0xb0000000);
        //设置SelectPicPopupWindow弹出窗体的背景
        this.setBackgroundDrawable(dw);
        //menuview添加ontouchlistener监听判断获取触屏位置如果在选择框外面则销毁弹出框
        menuview.setOnTouchListener((view, motionEvent) -> {
            int height = menuview.findViewById(R.id.ll_popup).getTop();
            int y = (int) motionEvent.getY();
            if (motionEvent.getAction() == MotionEvent.ACTION_UP) {
                if (y < height) {
                    dismiss();
                }
            }
            return true;
        });
    }

    /**
     * 设置按钮文字
     * @param index
     * @param text
     */
    public void setBtnItemText(int index, String text) {
        btnItems[index].setText(text);
    }

    /**
     * 批量设置按钮文字
     * @param texts
     */
    public void setBtnItemTexts(String[] texts) {
        int n = Math.min(texts.length, btnItems.length);
        for (int i = 0; i < n; i++) {
            btnItems[i].setText(texts[i]);
        }
    }

    /**
     * 设置按钮点击事件
     * @param index
     * @param listener
     */
    public void setBtnItemClickListener(int index, View.OnClickListener listener) {
        btnItems[index].setOnClickListener(listener);
    }

    /**
     * 设置取消按钮是否可见
     * @param visiable
     */
    public void setCancelBtnVisiable(boolean visiable) {
        if (visiable) {
            cancelBtn.setVisibility(View.VISIBLE);
        } else {
            cancelBtn.setVisibility(View.GONE);
        }
    }

    /**
     * 设置按钮字体颜色
     * @param color
     */
    public void setBtnItemsTextColor(int color) {
        for (int i = 0; i < btnItems.length; i++) {
            btnItems[i].setTextColor(color);
        }
    }

    /**
     * 设置按钮字体大小
     * @param size
     */
    public void setBtnitemsTextSize(float size) {
        for (int i = 0; i < btnItems.length; i++) {
            btnItems[i].setTextSize(size);
        }
    }

    /**
     * 设置取消按钮字体大小
     * @param size
     */
    public void setCancelBtnTextSize(float size) {
        cancelBtn.setTextSize(size);
    }

    /**
     * 设置取消按钮颜色
     * @param color
     */
    public void setCancelBtnTextColor(int color) {
        cancelBtn.setTextColor(color);
    }

    /**
     * 设置取消按钮文字
     * @param text
     */
    public void setCancelBtnText(String text) {
        cancelBtn.setText(text);
    }
}

效果如图：

image.png