Why opaque views are more effective on iPhone? -

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i tried find other reasons why opaque views better transparent. however, sensible reason came view behind opaque 1 doesn't need draw content @ place.

is wrong assumption , there other reasons?

thanks.

this right assumption. directly apple documentation:

opaque

a boolean value determines whether receiver opaque.

@property(nonatomic, getter=isopaque) bool opaque

discussion

this property provides hint drawing system how should treat view. if set yes, drawing system treats view opaque, allows drawing system optimize drawing operations , improve performance. if set no, drawing system composites view other content. default value of property yes.

an opaque view expected fill bounds entirely opaque content—that is, content should have alpha value of 1.0. if view opaque , either not fill bounds or contains wholly or partially transparent content, results unpredictable. should set value of property no if view or partially transparent.


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