I have a TextField:

TextField(
    controller: _controller,
    decoration: InputDecoration(hintText: 'Escribe aquí el título del evento',
                   prefixIcon: Icon(Icons.edit),
                  ),
     ),

and its controller:

TextEditingController _controller = TextEditingController();

My issue is when clicking on the TextField, the Keyboard is not shown.

EDIT

 Stack(
                overflow: Overflow.visible,
                alignment: Alignment.center,
                children: [

                  Positioned(
                    child: Container(
                      width: MediaQuery.of(context).size.width,
                      height: 190,

                      decoration: BoxDecoration(
                        image: DecorationImage(
                          colorFilter: ColorFilter.mode(ColoresApp.naranjaTop.withOpacity(0.2), BlendMode.dstOut),
                          image: NetworkImage(imagActualizado,),
                          fit: BoxFit.cover,
                        )
                      ),
                    ),
                  ),
                  Positioned(
                    top: 125,
                    child: Container(
                      decoration: BoxDecoration(
                        color: Colors.white,

                        border: Border.all(
                          color: Colors.white,
                          
                        ),
                        borderRadius: BorderRadius.all(Radius.circular(20))
                      ),
                      width: MediaQuery.of(context).size.width,
                      height: 280,
                      child: Column(
                        children: [
                          Padding(
                            padding: const EdgeInsets.all(8.0),
                            child: Row(
                              mainAxisAlignment: MainAxisAlignment.end,
                              children: [
                                Text("Público",style: TextStyle(fontSize: 10),),
                                Switch(
                                  value: isSwitched,
                                  onChanged: (value) {
                                   onSwitchChanged(value);
                                   nuevoEventoProvider.changeEsprivado(value);
                                  },
                                    activeTrackColor: ColoresApp.naranjaBottom,
                                    activeColor: ColoresApp.naranjaTop,
                                ),
                                Text("Privado",style: TextStyle(fontSize: 10)),

                              ],
                            ),
                          ),

                          Padding(
                            padding: const EdgeInsets.all(6.0),
                            child: TextField(
                              onTap: (){
                                print("PULSAdo");
                              },
                              controller: _controller,
                              decoration: InputDecoration(
                                hintText: 'Escribe aquí el título del evento',
                                border: InputBorder.none,

                                prefixIcon: Icon(Icons.edit),
                              ),
                            ),
                          ),

CodePudding user response：

instead of positon widget you can try with the Align

Stack(
            overflow: Overflow.visible,
            alignment: Alignment.center,
            children: [
              Positioned(
                child: Container(
                  width: MediaQuery.of(context).size.width,
                  height: 190,
                ),
              ),
              Align(
                alignment: Alignment.topLeft,
                child: Container(
                  decoration: BoxDecoration(
                      color: Colors.white,
                      border: Border.all(
                        color: Colors.white,
                      ),
                      borderRadius: BorderRadius.all(Radius.circular(20))),
                  width: MediaQuery.of(context).size.width,
                  height: 280,
                  child: Column(
                    children: [
                      Padding(
                        padding: const EdgeInsets.all(8.0),
                        child: Row(
                          mainAxisAlignment: MainAxisAlignment.end,
                          children: [
                            Text(
                              "Público",
                              style: TextStyle(fontSize: 10),
                            ),
                            Switch(
                              value: true,
                              onChanged: (value){
                                setState(() {
                                  value = !value;
                                });
                              },

                            ),
                            Text("Privado", style: TextStyle(fontSize: 10)),
                          ],
                        ),
                      ),
                      Padding(
                        padding: const EdgeInsets.all(6.0),
                        child: TextField(
                          onTap: () {
                            print("PULSAdo");
                          },
                          controller: _controller,
                          decoration: InputDecoration(
                            hintText: 'Escribe aquí el título del evento',
                            border: InputBorder.none,
                            prefixIcon: Icon(Icons.edit),
                          ),
                        ),
                      ),
                    ],
                  ),
                ),
              )
            ])

Output: