App screen with map and info panel should hide and show panel on button click or down sliding

To do that you have to change three things: First, transform from StatelessWidget to StatefulWidget; Second, create a variable for the height of the container and initialized whit the initial height; Thread, you have to change the container with an AnimatedContaire ad crate a function onPressd Like this:

AnimatedContainer(
    decoration: BoxDecoration(
      color: Colors.white,
      borderRadius: BorderRadius.circular(5.0),
      boxShadow: [
        BoxShadow(
          color: Colors.black,
          blurRadius: 6.0,
          spreadRadius: 0.5,
          offset: Offset(0.7, 0.7),
        ),
      ],
    ),
    duration: Duration(milliseconds: 1),
    height: heigntValue,
    child: Column(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: [
        SizedBox(
          child: Row(
            mainAxisAlignment: MainAxisAlignment.end,
            children: [
              RaisedButton(
                onPressed: () {
                  setState(() {
                    if (heigntValue == 350) {
                      heigntValue -= 300;
                    } else {
                      heigntValue += 300;
                    }
                    print(heigntValue);
                  });
                },
              ),
            ],
          ),
        ),
      ],
    ),
  ),