[FIXED] How to get flutter's textfield trigger?

Issue

i want to change my container's border color when the TextField is on focus. Is in Flutter this thing is ilegal? i've tried several way and it color can't be change when TextField is on focus or loss focus.

open it rel="nofollow noreferrer">https://i.postimg.cc/767RT4qW/Screenshot-45.png

here's my container and textfield code:

                      Container(
                        decoration: BoxDecoration(
                          border: Border.all(
                            color: _myFocusNode.hasFocus
                                ? Colors.black38
                                : Colors.blue,
                            width: 2,
                          ),
                          borderRadius: BorderRadius.circular(8),
                        ),
                        child: Row(
                          mainAxisAlignment: MainAxisAlignment.center,
                          children: [
                            const Padding(
                              padding: EdgeInsets.symmetric(
                                horizontal: 10,
                              ),
                              child: Icon(
                                Icons.alternate_email_rounded,
                                color: Colors.black38,
                              ),
                            ),
                            Flexible(
                              child: TextField(
                                focusNode: _myFocusNode,
                                autofocus: true,
                                style: const TextStyle(
                                  fontSize: 16,
                                  fontWeight: FontWeight.w500,
                                ),
                                cursorHeight: 24,
                                cursorColor: Colors.grey,
                                decoration: const InputDecoration(
                                  border: InputBorder.none,
                                  suffixIcon: SizedBox(
                                    height: 24,
                                    width: 24,
                                  ),
                                  hintText: 'Input your email',
                                  hintStyle: TextStyle(
                                    color: Colors.black38,
                                  ),
                                ),
                              ),
                            ),
                          ],
                        ),
                      ),
                    ],
                  ),

Solution

Try this:

FocusScope(
  child: Focus(
    onFocusChange: (focus) => print("focus: $focus"),
    child: TextField(
      decoration: const InputDecoration(labelText: 'City'),
    )
  )
)

Answered By - Ricardo Rodrigues
Answer Checked By - Senaida (JavaFixing Volunteer)