tabBarItem设置背景色，标题

//宽度
CGFloat wid =
kScreenWidth /(vcCount-1)+1;
CGFloat Hig =
49;
//改变图片的大小
UIImage *image = [self
scaleImageToSize:[UIImage
createImageWithColor:IWColor(45,
70, 136)]
size:CGSizeMake(wid, Hig)];
UIImage *selectedImage = [self
scaleImageToSize:[UIImage
createImageWithColor:IWColor(61,
83, 145)]
size:CGSizeMake(wid, Hig)];
//背景图片显示
[childVc.tabBarItem
setImage:[image imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]];
[childVc.tabBarItem
setSelectedImage:[selectedImage
imageWithRenderingMode:UIImageRenderingModeAlwaysOriginal]];
//背景图片恰好显示在tabbar 上下 或者左右的绝对值要相等，否则会有每次点击按钮，按钮背景图片一致变大的问题
[childVc.tabBarItem
setImageInsets:UIEdgeInsetsMake(5,
0, -5,
0)];
//背景标题的大小
[childVc.tabBarItem
setTitleTextAttributes:@{NSFontAttributeName:[UIFont
boldSystemFontOfSize:20],NSForegroundColorAttributeName:[UIColor
whiteColor]}
forState:UIControlStateNormal];
//背景图片恰到位置
[childVc.tabBarItem
setTitlePositionAdjustment:UIOffsetMake(0, -16)];