导航栏背景色 标题颜色以及返回键自定义

1.导航栏背景色设置：

//设置为半透明

self.navigationController.navigationBar.translucent = YES;

//设置背景色及透明度

[self.navigationController.navigationBar setBackgroundImage:[UIImage imageWithColor:[UIColor colorWithRed:0 green:0 blue:0 alpha:0.75]] forBarMetrics:UIBarMetricsDefault];

2.导航栏标题颜色：

[self.navigationController.navigationBar setTintColor:[UIColorwhiteColor]];

3.自定义返回键：

UIImage *backImage = [UIImage imageNamed:@"route_tab_back"];

UIButton *backBtn = [UIButton buttonWithType:UIButtonTypeCustom];

[backBtn setImage:backImage forState:UIControlStateNormal];

backBtn.frame = CGRectMake(0, 0, backImage.size.width, backImage.size.height);

[backBtn addTarget:self action:@selector(handleBackButton) forControlEvents:UIControlEventTouchUpInside];

UIBarButtonItem *item = [[UIBarButtonItem alloc] initWithCustomView:backBtn];

self.navigationController.navigationItem.leftBarButtonItem = item;