Flutter DropDownButton自适应宽度

Question

I have a DropDownButton , the width default is the longest DropDownMenuItem.

But I want that for example when the value is Âge: Tout the DropDownButton adapt his width to the text.

return DropdownButton(
        icon: const Icon(Icons.arrow_drop_down_rounded, color: Colors.white),
        dropdownColor: Colors.orange,
        value: _filterCategory,
        items: _categories.map((String e) {
          return DropdownMenuItem(
              value: e,
              child: Text("Catégories : "+e,style: const TextStyle(fontSize: 14, color: Colors.white))
          );
        }).toList(),
        onChanged: (value) {
          setState(() {
            //DATA
          });
        }
    );

Answer 1

Try using an input Decoration and a SizedBox

InputDecorator createTemplateWidget() {
    DropdownButton<MyClass> myDropdownButton =
        DropdownButton<MyClass>(
            items: items,
            isDense: true,
            value: _template,
            isExpanded: true,
            onChanged: (MyClass value) {
              setState(() {
                this._myVariable = value;
              });
            });
    return InputDecorator(
        decoration: const InputDecoration(
            icon: const Icon(Icons.location_city),
            hintText: "City",
            labelText: "Select a Type"),
        child: Row(mainAxisAlignment: MainAxisAlignment.start, children: [
      Container(width: 600.0, child: myDropdownButton),
      SizedBox()
    ]));
  }
}