Check out example codes for "align column to center of flex flutter". It will help you in understanding the concepts better.

Code Example 1

// If you want the whole table to be Centered, use the mainAxisAlignment property of Column.
///Column
mainAxisAlignment: MainAxisAlignment.center //Center Column contents vertically,
crossAxisAlignment: CrossAxisAlignment.center //Center Column contents horizontally,

///Row
mainAxisAlignment: MainAxisAlignment.center //Center Row contents horizontally,
crossAxisAlignment: CrossAxisAlignment.center //Center Row contents vertically,

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