dart - Show/hide widgets in Flutter programmatically

Question

In Android, every single View subclass has a setVisibility() method that allows you modify the visibility of a View object

There are 3 options of setting the visibility:

• Visible: Renders the View visible inside the layout
• Invisible: Hides the View, but leaves a gap that is equivalent to what the View would occupy if it were visible
• Gone: Hides the View, and removes it entirely from the layout. It's as if its height and width were 0dp

Is there something equivalent to the above for Widgets in Flutter?

For a quick reference: https://developer.android.com/reference/android/view/View.html#attr_android:visibility

Answer 1

Invisible: The widget takes physical space on the screen but not visible to user.

Gone: The widget doesn't take any physical space and is completely gone.

---

Invisible example

Visibility(
  child: Text("Invisible"),
  maintainSize: true, 
  maintainAnimation: true,
  maintainState: true,
  visible: false, 
),

Gone example

Visibility(
  child: Text("Gone"),
  visible: false,
),

---

You can also use if or if-else.

• Using if

  Column(
    children: <Widget>[
      Text('Good Morning'), // Always visible
      if (hasName) Text(' Mr ABC'), // Visible only if 'hasName' is true
    ],
  ) 
  

• Using if-else

  Column(
    children: <Widget>[
      // Only one of them is visible based on 'isMorning' condition.
      if (isMorning) Text('Good Morning')
      else Text ('Good Evening'),
    ],
  )