How can use if statement with Container widget in flutter

Question

I want to use if statement with container widget like this code :

if (int.parse(m_id) > int.parse(cm_id) || int.parse(d_id) > 4)
    {
      Container(
         width: 0.23 * size,
         height: 0.23 * size,
         child: Image.asset('assets/images/days/day4k.png'),
     ),
}

But it gets error :

The element type 'Set<Container>' can't be assigned to the list type 'Widget'

is there a way to fix this error ?

Unfortunately you cannot have an `else` statement, use another `if` or move the code into a function returning a widget. — Yann39, Aug 04 '20 at 13:00
@ByteMe Oh sure sorry, was confused with something else, just tried and it indeed works, cheers ! — Yann39, Aug 04 '20 at 13:58
Does this answer your question? [How to use conditional statement within child attribute of a Flutter Widget (Center Widget)](https://stackoverflow.com/questions/49713189/how-to-use-conditional-statement-within-child-attribute-of-a-flutter-widget-cen) — Yann39, Aug 04 '20 at 13:59

ByteMe · Accepted Answer · 2020-08-04T13:17:04.733

Braces should not be used in if the if statement is inside a flutter widget

if (int.parse(m_id) > int.parse(cm_id) || int.parse(d_id) > 4)
      Container(
         width: 0.23 * size,
         height: 0.23 * size,
         child: Image.asset('assets/images/days/day4k.png'),
   ),

The above should work just fine

If you do happen do have an if else statement, you still won't employ the use of braces, just remove the , at the end of the of the first widget

if (int.parse(m_id) > int.parse(cm_id) || int.parse(d_id) > 4)
    Container(
       width: 0.23 * size,
       height: 0.23 * size,
       child: Image.asset('assets/images/days/day4k.png'),
    ) //no comma here
else
    Container(), //comma here

Also, If you have an else if statement, you would also approach it in the same way

if (int.parse(m_id) > int.parse(cm_id) || int.parse(d_id) > 4)
    Container(
       width: 0.23 * size,
       height: 0.23 * size,
       child: Image.asset('assets/images/days/day4k.png'),
    ) //no comma here
else if (condition here)
    Container() //no comma here
else
    Container(), //comma here

You're welcome. I've also updated my answer to show how to do in an `else if` statement in case you need that in the future — ByteMe, Aug 04 '20 at 13:18

score 0 · Answer 2 · answered Aug 04 '20 at 12:58

0

It's must works:

if (int.parse(m_id) > int.parse(cm_id) || int.parse(d_id) > 4)...[
    Container(
         width: 0.23 * size,
         height: 0.23 * size,
         child: Image.asset('assets/images/days/day4k.png'),
     ),
]

answered Aug 04 '20 at 12:58

Captivity

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5
21

so if i have else statement after if, how can i put else? – Sermed Berwari Aug 04 '20 at 13:01
`else` not, but you can write code like this: `if (!(int.parse(m_id) > int.parse(cm_id) || int.parse(d_id) > 4))...[ this is like else ]` – Captivity Aug 04 '20 at 13:08

How can use if statement with Container widget in flutter

2 Answers2