FLutter自定義dialog並可傳回調函數

自定義dialog代碼：

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

class addLabelPageDialog extends StatefulWidget {
  final confirmCallback;
  const addLabelPageDialog(
      {
        Key key,
        this.confirmCallback
      }) : super(key: key);

  @override
  State<StatefulWidget> createState() {
    return _addLabelPageDialog();
  }
}

class _addLabelPageDialog extends State<addLabelPageDialog>{
  final controller = TextEditingController();
  String inputValuue = "";

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      child: Material(//遮罩層
        type: MaterialType.transparency, //透明類型
        //透明度
        child: new Center(
          child: Container(
              width: 400,
              height: 300,
              decoration: BoxDecoration(
                color: Colors.white,
                shape: BoxShape.rectangle,
                //可以設置角度，BoxShape.circle直接圓形
                borderRadius: BorderRadius.all(Radius.circular(15.0)),
              ),
              child: Column(
                children: <Widget>[
                  Container(
                    width: 400,
                    height: 60,
                    alignment: Alignment.center,
                    decoration: BoxDecoration(
                      color: Colors.red,
                      shape: BoxShape.rectangle,
                      //可以設置角度，BoxShape.circle直接圓形
                      borderRadius: BorderRadius.only(
                          topLeft: Radius.circular(15.0),
                          topRight: Radius.circular(15.0)),
                    ),
                    child: Text(
                      "新建標簽",
                      style: TextStyle(
                        color: Colors.white,
                        fontSize: 30,
                      ),
                    ),
                  ),
                  Container(
                    padding: new EdgeInsets.all(30),
                    color: Colors.white,
                    child: Container(
                        padding: new EdgeInsets.all(10),
                        decoration: BoxDecoration(
                          color: Color(0xFFFFCDD2),
                          border: Border.all(color: Colors.red, width: 1.0),
                          borderRadius: BorderRadius.circular(5.0),
                        ),
                        child: TextFormField(
                          style: TextStyle(fontSize: 20,),
                          textAlign: TextAlign.center,
                          controller: controller,
                          onFieldSubmitted: (val) {
                            print("============鍵盤按回車完成=============" + val);
                            inputValuue = val;
                          },
                          decoration: InputDecoration(
                              hintText: '內容',
                              border: UnderlineInputBorder(
                                  borderSide: BorderSide.none)),
                        )),
                  ),
                  Container(
                    padding: new EdgeInsets.only(top: 30),
                    child: GestureDetector(
                      child: Container(
                        width: 100,
                        height: 50,
                        alignment: Alignment.center,
                        decoration: BoxDecoration(
                          color: Colors.red,
                          borderRadius: BorderRadius.circular(10.0),
                        ),
                        child: Text("確定", style: TextStyle(fontSize: 25,color: Colors.white),),
                      ),
                      onTap: (){
                        //通過回調函數回傳新建的標簽內容
                        widget.confirmCallback(inputValuue);
                        Navigator.of(context).pop();
                      },
                    ),
                  ),
                ],
              )),
        ),
      ),
      onTap: () {
        print("關閉dialog");
        Navigator.pop(context); //關閉對話框
      },
    );
  }
}




調用方式：

onTap: () {//點擊事件觸發
  print("添加標簽");
  return showDialog<Null>(
      context: context, //BuildContext對象
      barrierDismissible: false,
      builder: (BuildContext context) {
        return addLabelPageDialog(confirmCallback: confirmCallback);
      });
},

//回調函數，接收新建的標簽內容
void confirmCallback(value){
  if(value == null || value == ""){
    return;
  }
  if(labelList.contains(value)){
    Fluttertoast.showToast(msg: "已添加，請勿重復添加",gravity: ToastGravity.CENTER);
  }
  print("添加的標簽內容：：：：" + value);
  setState(() {
    labelList.add(value);
  });
}

so easy!!!加油Flutter開發者們！！！祝一路順風！！！！！！！！！！！！！！！！！！