在UIButton的selected設為TRUE後,需要在按鈕高亮時,顯示自定義的背景圖。
經研究hightLighted和selected這兩個狀态是可以重疊的,就是button可以同時處于selectec和highlighted兩個狀态下。
從UIControlState的定義也可以看出:
typedef NS_OPTIONS(NSUInteger, UIControlState) {
UIControlStateNormal = 0,
UIControlStateHighlighted = 1 << 0, // used when UIControl isHighlighted is set
UIControlStateDisabled = 1 << 1,
UIControlStateSelected = 1 << 2, // flag usable by app (see below)
UIControlStateApplication = 0x00FF0000, // additional flags available for application use
UIControlStateReserved = 0xFF000000 // flags reserved for internal framework use
};
設定這種狀态重疊情景時的背景圖:
[button setBackgroundImage:[UIImage imageNamed:@"seled_highLight.png"] forState:UIControlStateSelected| UIControlStateHighlighted];