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Android

Jovy Ong
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Jovy Ong
Front End Web Development Techdegree Student 14,858 Points
Posted by Jovy Ong
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Jovy Ong
Front End Web Development Techdegree Student 14,858 Points

Why use 0dp instead of match_constraint?

Going through the Android TD, I'm now at the ConstraintLayout lecture. My question is why did the instructor use 0dp as the layout_width instead of declaring it as match_constraint? Does it make a difference? Because it seems both do the job but match_constraint is better for readability IMO. Appreciate any help on this.

2 Answers

Lauren Moineau
Lauren Moineau
9,483 Points

You're welcome :)

Lauren Moineau
Lauren Moineau
9,483 Points
Lauren Moineau
Lauren Moineau
9,483 Points

In a ConstraintLayout, "0dp" means "match_constraint".

You will see that you cannot set layout_width or layout_height to "match_constraint" in your XML text file. You will get an error. It has to be set to "0dp". Similarly, in Android Studio's Layout Editor, when you set a view's layout_width or layout_height to "match_contstraint", it automatically displays "0dp".

Hope this helps