h文件里:
@property(nonatomic, readonly) NSUInteger preSelectedIndex;//上次选中的index
m文件里:
- (void)setSelectedIndex:(NSUInteger)selectedIndex {
if (self.selectedIndex != selectedIndex) {
_preSelectedIndex = self.selectedIndex;
}
[super setSelectedIndex:selectedIndex];
}
- (void)tabBar:(UITabBar *)tabBar didSelectItem:(UITabBarItem *)item {
NSUInteger index = [tabBar.items indexOfObject:item];
if (index != self.selectedIndex) {
_preSelectedIndex = self.selectedIndex;
}
}