设置纯数字键盘:

 keyboardType: const TextInputType.numberWithOptions(decimal: true),

事件类:

import 'package:flutter/cupertino.dart';
import 'package:giftbook/base/InputDoneView.dart';
class KeyboardOverlay{
  static OverlayEntry? _overlayEntry;

  static showOverlay(BuildContext context) {
    if(_overlayEntry != null) {
      return;
    }

    OverlayState? overlayState = Overlay.of(context);
    _overlayEntry = OverlayEntry(builder: (context) {
      return Positioned(
          bottom: MediaQuery.of(context).viewInsets.bottom,
          right: 0.0,
          left: 0.0,
          child: const InputDoneView());
    });

    overlayState!.insert(_overlayEntry!);
  }

  static removeOverlay() {
    if (_overlayEntry != null) {
      _overlayEntry!.remove();
      _overlayEntry = null;
    }
  }
}

视图类:

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';

class InputDoneView extends StatelessWidget {
  const InputDoneView({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Container(
        width: double.infinity,
        color: CupertinoColors.extraLightBackgroundGray,
        child: Align(
            alignment: Alignment.topRight,
            child: Padding(
              padding: const EdgeInsets.only(top: 4.0, bottom: 4.0),
              child: CupertinoButton(
                padding: const EdgeInsets.only(
                    right: 24.0, top: 8.0, bottom: 8.0),
                onPressed: () {
                  FocusScope.of(context).requestFocus(FocusNode());
                },
                child: const Text("Done",
                    style: TextStyle(color: CupertinoColors.activeBlue,)
                ),
              ),
            )
        )
    );
  }
}

3.使用

FocusNode numberFocusNode = FocusNode();

  numberFocusNode.addListener(() {
      bool hasFocus = numberFocusNode.hasFocus;
      if (hasFocus) {
        KeyboardOverlay.showOverlay(context);
      } else {
        KeyboardOverlay.removeOverlay();
      }
    });


    numberFocusNode.dispose();


    focusNode: numberFocusNode,