flutter – 在TextFormField上捕捉点击事件

我使用GestureDetector将TextFormField作为子元素执行,但点击它时没有任何东西触发：

@override
  Widget build(BuildContext context) {
    return new Scaffold(
      key: _scaffoldKey,appBar: new AppBar(title: const Text('Recherche de sorties')),body: new DropdownButtonHideUnderline(
        child: new Form(
          key: _formKey,autovalidate: _autovalidate,child: new ListView(
              padding: const EdgeInsets.symmetric(horizontal: 16.0),children: <Widget>[
                new DatePicker(
                  labelText: 'Date',selectedDate: widget.request.dateDebut,initialDate: widget.request.dateDebut,firstDate: new DateTime.now().add(new Duration(days: -1)),lastDate: new DateTime.now().add(new Duration(days: 365 * 4)),selectDate: (DateTime value) {
                    setState(() {
                      widget.request.dateDebut = value;
                    });
                  },datePickerMode: DatePickerMode.day,icon: const Icon(Icons.date_range),),new InputDecorator(
                  decoration: const InputDecoration(
                    labelText: 'Rayon',hintText: '-- Choisissez un rayon --',icon: const Icon(Icons.settings_backup_restore),isEmpty: widget.request.rayon == null,child: new DropdownButton<String>(
                    value: widget.request.rayon.toString(),isDense: true,onChanged: (String newValue) {
                      setState(() {
                        widget.request.rayon = int.parse(newValue);
                      });
                    },items: _rayons.keys.map((int key) {
                      return new DropdownMenuItem<String>(
                        value: key.toString(),child: new Text(_rayons[key]),);
                    }).toList(),new GestureDetector(
                  onTap: () async {
                    print("Container clicked");

                    Prediction p = await showGooglePlacesAutocomplete(
                        context: context,apiKey: Consts.googlePlacesApiKey,mode: Mode.fullscreen,language: "fr",components: [new Component(Component.country,"fr")]);

                    if (p != null) {
                      (_scaffoldKey.currentState).showSnackBar(
                          new SnackBar(content: new Text(p.description)));
                    }
                  },child: new TextFormField(
                    // controller: controller,decoration: const InputDecoration(
                      icon: const Icon(Icons.room),hintText: 'Où êtes vous ?',labelText: 'Localisation',new Container(
                    padding: const EdgeInsets.all(20.0),alignment: Alignment.center,child: new Align(
                      alignment: const Alignment(0.0,-0.2),child: new ButtonBar(
                        mainAxisSize: MainAxisSize.min,children: <Widget>[
                          new RaisedButton(
                            child: const Text('ANNULER'),onPressed: _fermerCritereRecherche,new RaisedButton(
                            child: const Text('VALIDER'),onPressed: _valider,],)),]),);
  }

如果我更换：

new GestureDetector(
          onTap: () async {
            print("Container clicked");

            Prediction p = await showGooglePlacesAutocomplete(
                context: context,"fr")]);

            if (p != null) {
              (_scaffoldKey.currentState).showSnackBar(
                  new SnackBar(content: new Text(p.description)));
            }
          },child: new TextFormField(
            // controller: controller,decoration: const InputDecoration(
              icon: const Icon(Icons.room),

通过一个简单的容器,它正在工作：

new GestureDetector(
          onTap: () async {
            print("Container clicked");

            Prediction p = await showGooglePlacesAutocomplete(
                context: context,child: new Container(
             width: 80.0,height: 80.0,margin: new EdgeInsets.all(10.0),color: Colors.black),

您有任何想法如何使GestureDetector与TextFormField一起使用吗？也许与控制器,但我尝试没有任何成功
提前致谢