webView||WkWebView自定义关闭按钮(微信加载网页效果)

这篇文章主要处理加载多层网页返回的问题,其实功能很简单,自己当时做的时候没带脑子,找了好久资料没有想要的(其实是自己不长心),记录一下.
1.在导航上创建一个关闭按钮的btn,默认alpha =0

 UIButton *btn =[UIButton buttonWithType:UIButtonTypeCustom];
    [self.nav addSubview:btn];
    [btn mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.offset(WIDTH_CONSTARIN(60));
        make.top.offset(STATUS_BAR_HEIGHT);
        make.size.mas_equalTo(CGSizeMake(60, 44));
    }];
    btn.alpha =0;
    
    [btn setTitle:@"关闭" forState:UIControlStateNormal];
    btn.titleLabel.font =FONT(16.f);
    [btn setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
    [btn addTarget:self action:sel_registerName("closeClick") forControlEvents:UIControlEventTouchUpInside];
    _closeBtn =btn;

2.处理关闭按钮是否显示(以wkWeb代理为例)

//index不用解释了
//pageBack参数主要是为了放置index在返回时调用didFinishNavigation再次+1的问题,可以理解为是push和pop,
@property (nonatomic, assign) NSInteger index;//记录加载的页数
@property (nonatomic, assign) BOOL pageBack;//判断是否点击了返回

// 页面加载完成之后调用
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation{
    if (!_pageBack) {//是新页面 index 就+1
        ++_index;
    }
    _pageBack = NO;
    if (_index >=2 ) {//页数大于等于2 关闭按钮就显示
        _closeBtn.alpha =1;
    }else{
        _closeBtn.alpha =0;
    }

}

3.处理返回和关闭逻辑

//返回操作
- (void)leftViewClick {
    _pageBack = YES;//是pop,返回结束后,index不用+1
    if (_index >=2) {
        _index--;
        [self.WKWebView goBack];
    }else{//就一页了 可以直接退出去
        [self.navigationController popViewControllerAnimated:YES];
    }
    
}

//关闭操作
- (void)closeClick {
    [self.loading removeFromSuperview];
    [self.navigationController popViewControllerAnimated:YES];

}