Flutter:如何使对话框的按钮居中？

Question

我的对话框有问题，按钮不会居中，即使我已经有了

mainAxisAlignment: MainAxisAlignment.center, 
crossAxisAlignment: CrossAxisAlignment.center 

在里面。我的代码:

actions: <Widget>[
          Row(
            mainAxisAlignment: MainAxisAlignment.center,
            crossAxisAlignment: CrossAxisAlignment.center,
            children: <Widget>[
              Container(
                width: MediaQuery.of(context).size.width * 0.20,
                child: RaisedButton(
                  child: new Text(
                    'Save',
                    style: TextStyle(color: Colors.white),
                  ),
                  color: Color(0xFF121A21),
                  shape: new RoundedRectangleBorder(
                    borderRadius: new BorderRadius.circular(30.0),
                  ),
                  onPressed: () {
                    saveIssue();
                    Navigator.of(context).pop();
                  },
                ),
              ),
              SizedBox(
                width: MediaQuery.of(context).size.width * 0.01,
              ),
              Container(
                width: MediaQuery.of(context).size.width * 0.20,
                child: RaisedButton(
                  child: new Text(
                    'Cancel',
                    style: TextStyle(color: Colors.white),
                  ),
                  color: Color(0xFF121A21),
                  shape: new RoundedRectangleBorder(
                    borderRadius: new BorderRadius.circular(30.0),
                  ),
                  onPressed: () {
                    Navigator.of(context).pop();
                  },
                ),
              ),
              SizedBox(
                height: MediaQuery.of(context).size.height * 0.02,
              ),
            ],
          )
        ],                                                                                          

我的界面:

Link for my UI

Answer 1

根据source code , 使用 ButtonBar 强制对齐，所以如果你想改变对齐方式，你应该用 ButtonBarTheme 包裹 AlertDialog。

class TestDialog extends StatelessWidget {
  const TestDialog({Key key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return ButtonBarTheme(
      data: ButtonBarThemeData(alignment: MainAxisAlignment.center),
      child: AlertDialog(
        content: Text("CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_CONTENT_"),
        actions: <Widget>[
          Row(
            mainAxisSize: MainAxisSize.max,
            //mainAxisAlignment: MainAxisAlignment.center,
            //crossAxisAlignment: CrossAxisAlignment.center,
            children: <Widget>[
              Container(
                width: MediaQuery.of(context).size.width * 0.20,
                child: RaisedButton(
                  child: new Text(
                    'Save',
                    style: TextStyle(color: Colors.white),
                  ),
                  color: Color(0xFF121A21),
                  shape: new RoundedRectangleBorder(
                    borderRadius: new BorderRadius.circular(30.0),
                  ),
                  onPressed: () {
                    Navigator.of(context).pop();
                  },
                ),
              ),
              SizedBox(
                width: MediaQuery.of(context).size.width * 0.01,
              ),
              Container(
                width: MediaQuery.of(context).size.width * 0.20,
                child: RaisedButton(
                  child: new Text(
                    'Cancel',
                    style: TextStyle(color: Colors.white),
                  ),
                  color: Color(0xFF121A21),
                  shape: new RoundedRectangleBorder(
                    borderRadius: new BorderRadius.circular(30.0),
                  ),
                  onPressed: () {
                    Navigator.of(context).pop();
                  },
                ),
              ),
              SizedBox(
                height: MediaQuery.of(context).size.height * 0.02,
              ),
            ],
          )
        ],
      )
    );
  }
}

结果: