All language subtitles for 40. Outputting Widgets Conditionally

Now let's start with the ternary expression and therefore here, you first of all have your condition.

The condition here could be without the if keyword,

that's how you'll write a ternary expression.

So the condition here can be the same condition as up there,

is the question index smaller than the question length? If this is the case, then you add a question mark,

this will then mark the border to the code which should run if this is true.

So the thing after the question mark is used

if this condition is true and then you need to add a colon after the code block that should be used

if this is true

and this part after the question mark must only be one expression, here since it's a lot of lines, it

looks like it's more than one expression but in the end, it's only the column here,

right?

It's only the column, all the other stuff is in the column.

So only the column here is created

if that is true and therefore after the column down there, we add a colon

and now we have the so-called else block.

We didn't have an else block up there but we could add it here as well,

you can add else here and then you can define code that should run if the condition is not met,

so if this here, if this returns false, then you will go into the else block. By the way in if statements

like this here,

you can also have else if statements where you could add other conditions which are checked if the first

condition is not met but let's ignore that for now. For the ternary expression here down in our body,

we don't have else if but we do have our main code,

if the condition is met and then after the colon, we have our else block

and now that could be a center widget which is another widget baked into Flutter that centers all

the content horizontally and vertically on the page.

It takes a child and that is then the widget which should be centered

and this could simply be some text like you did it and let's add a trailing comma here, reformat everything

and now we have a ternary expression. If we now reload this application and we go back,

now I can select my answers but after the third button click, we don't get the error but we get

you did it

and that's of course way nicer and already a better user experience.