//1.改变大小：

UITabBarController *tabBarController = (UITabBarController *)self.window.rootViewController;

UITabBar *tabBar = tabBarController.tabBar;

for (UITabBarItem *item in tab.tabBar.items) {

item.imageInsets = UIEdgeInsetsMake(2, 2, 2,2);

}

//或者改变图片的大小即可，特别是@2x.png的图片大小

//2.改变颜色

[tabBar setSelectedImageTintColor:[UIColor redColor]];//如果没有选中的图片，这个可以改变图片颜色(ios7)

tabBar.tintColor=[UIColor greenColor];//ios8下

//3.消除tabbar边框

在appdelegate的程序启动处：

[[UITabBar appearance] setShadowImage:[[UIImage alloc]init]];

[[UITabBar appearance] setBackgroundImage:[[UIImage alloc]init]];

//4.设置tabbar item原始图标与原始选中图标，而不是系统自动填充的颜色

UITabBar*tabBar = _tabBarController.tabBar;

UITabBarItem*item0= [tabBar.itemsobjectAtIndex:0];

UITabBarItem*item1= [tabBar.itemsobjectAtIndex:1];

UITabBarItem*item2= [tabBar.itemsobjectAtIndex:2];

UITabBarItem*item3= [tabBar.itemsobjectAtIndex:3];

// 5.对item设置相应地图片

item0.selectedImage= [[UIImageimageNamed:@"recognize-1"]imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];;

item0.image= [[UIImageimageNamed:@"recognize"]imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];

item1.selectedImage= [[UIImageimageNamed:@"life-1"]imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];;

item1.image= [[UIImageimageNamed:@"life"]imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];

item2.selectedImage= [[UIImageimageNamed:@"edit-1"]imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];;

item2.image= [[UIImageimageNamed:@"edit"]imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];

item3.selectedImage= [[UIImageimageNamed:@"setting-1"]imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];;

item3.image= [[UIImageimageNamed:@"setting"]imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal];

//6.设置tabbar背景图片

UIView*backView = [[UIViewalloc]initWithFrame:CGRectMake(0,0, Main_Screen_Width,49)];

backView.backgroundColor= [UIColorredColor];

[self.tabBarinsertSubview:backViewatIndex:0];

self.tabBar.opaque=YES;