iOS - 设置导航栏之标题栏居中、标题栏的背景颜色

本章实现效果:



Untitled.gif

前言:
项目中很多需求是要求自定义标题栏居中的,本人最近就遇到这中需求,如果用系统自带的titleView设置的话,不会居中,经过尝试，发现titleview的起点位置和尺寸依赖于leftBarButtonItem和rightBarButtonItem的位置。下面给出我的解决方案

首先自定义一个标题View

#import <UIKit/UIKit.h>
@interface CustomTitleView : UIView
@property (nonatomic, copy) NSString *title;
@end

#import "CustomTitleView.h"
#import "Masonry.h"

@interface CustomTitleView ()
@property(nonatomic,strong)UILabel * titleLabel;//标题label
@property (nonatomic,strong) UIView *contentView;

@end

@implementation CustomTitleView

- (instancetype)init
{
self = [super init];
if (self) {
[self addSubview:self.contentView];
[self.contentView mas_makeConstraints:^(MASConstraintMaker *make) {
make.left.greaterThanOrEqualTo(self);
make.right.lessThanOrEqualTo(self);
make.center.equalTo(self);
make.bottom.top.equalTo(self);
}];

[self.contentView addSubview:self.titleLabel];

[self.titleLabel mas_makeConstraints:^(MASConstraintMaker *make) {
make.centerY.equalTo(self.contentView);
make.centerX.equalTo(self.contentView);
}];

}
return self;
}

- (void)setFrame:(CGRect)frame
{
[super setFrame:frame];
[self layoutIfNeeded];
}

- (UIView *)contentView
{
if (!_contentView) {
_contentView = [UIView new];
}
return _contentView;
}

-(UILabel *)titleLabel
{
if (!_titleLabel) {
_titleLabel = [[UILabel alloc] init];
_titleLabel.textColor = [UIColor whiteColor];
_titleLabel.font = [UIFont boldSystemFontOfSize:17];
_titleLabel.lineBreakMode = NSLineBreakByTruncatingTail;
_titleLabel.textAlignment = NSTextAlignmentCenter;
[_titleLabel setContentCompressionResistancePriority:UILayoutPriorityDefaultLow forAxis:UILayoutConstraintAxisHorizontal];
_titleLabel.backgroundColor = [UIColor redColor];
}
return _titleLabel;
}

- (void)setTitle:(NSString *)title
{
self.titleLabel.text = title;
}

具体用法如下:
在当前页面的控制中只要写,即可实现上图的效果

CustomTitleView *titleView = [[CustomTitleView alloc] init];
titleView.backgroundColor = [UIColor greenColor];
titleView.frame = CGRectMake(0, 0, PDScreeenW, 44);
titleView.title = @"我是标题";
self.navigationItem.titleView = titleView;
self.titleView = titleView;

UIBarButtonItem *rightBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"" style:UIBarButtonItemStylePlain target:self action:nil];
self.navigationItem.rightBarButtonItem = rightBarButtonItem;