A.DrawRoundRect B.DrawRect C.DrawRound D.SetRoundRect
A.setWidth B.setStroke C.setStrokeWidth D.width=
A.取值match_parent表示与上级视图一样尺寸 B.取值wrap_content表示按照自身内容的实际尺寸 C.weight权重 D.直接指定了具体的dp数值