2018 自适应WKWebView高度

ArticalDetailCell.m

//
//  ArticalDetailCell.m
//  BlockChainNews
//
//  Created by zsm on 2018/5/30.
//  Copyright © 2018年 XinHuoKeJi. All rights reserved.
//

#import "ArticalDetailCell.h"

@interface ArticalDetailCell()
@property (weak, nonatomic) IBOutlet UILabel *titileLab;
@property (weak, nonatomic) IBOutlet UILabel *timeLab;

@end

@implementation ArticalDetailCell


- (void)awakeFromNib {
    [super awakeFromNib];
    // Initialization code
    self.selectionStyle = UITableViewCellSelectionStyleNone;

    self.myWebView.backgroundColor = [UIColor clearColor];
    self.myWebView.scrollView.scrollEnabled = NO;
    [self.myWebView setUserInteractionEnabled:NO];//是否支持交互
    [self.myWebView.scrollView addObserver:self forKeyPath:@"contentSize" options:NSKeyValueObservingOptionNew context:nil];
    self.myWebView.navigationDelegate = self;
    self.myWebView.UIDelegate = self;
}
#pragma mark - WKNavigationDelegate
/* 页面开始加载 */
- (void)webView:(WKWebView *)webView didStartProvisionalNavigation:(WKNavigation *)navigation{
//    [SVProgressHUD show];
}
/* 开始返回内容 */
- (void)webView:(WKWebView *)webView didCommitNavigation:(WKNavigation *)navigation{
    
}
/* 页面加载完成 */
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation{

    [SVProgressHUD dismiss];
    if (webView.isLoading) {
        return;
    }
    __block CGFloat webViewHeight=0;
    //获取内容实际高度（像素）@"document.getElementById(\"content\").offsetHeight;"
    [webView evaluateJavaScript:@"document.body.offsetHeight" completionHandler:^(id _Nullable result,NSError * _Nullable error) {
        // 此处js字符串采用scrollHeight而不是offsetHeight是因为后者并获取不到高度，看参考资料说是对于加载html字符串的情况下使用后者可以，但如果是和我一样直接加载原站内容使用前者更合适
        //获取页面高度，并重置webview的frame
        webViewHeight = [result floatValue];
        NSLog(@"%f",webViewHeight);
        if (self.webViewHeightChanged) {
            self.webViewHeightChanged(webViewHeight);
        }
 
    }];
    
//    [webView evaluateJavaScript:@"document.body.offsetHeight" completionHandler:^(id _Nullable clientheight_str, NSError * _Nullable error) {
//        float clientheight = [clientheight_str floatValue];
//        webView.frame = CGRectMake(15, 10, kScreenWidth - 30, clientheight);
//
//        [webView evaluateJavaScript:@"" completionHandler:^(id _Nullable, NSError * _Nullable error) {
//
//        }];
//    }];
    

//    NSString * clientheight_str = [webView stringByEvaluatingJavaScriptFromString: @"document.body.offsetHeight"];
//    float clientheight = [clientheight_str floatValue];
//    //设置到WebView上
//    webView.frame = CGRectMake(15, 10, kScreenWidth - 30, clientheight);
//
//
//    //下面这样写就是获取到比较准确的内容高度，不需要再进行其他计算了
//    //获取内容实际高度（像素）
//    NSString * height_str= [webView stringByEvaluatingJavaScriptFromString: @"document.getElementById('webview_content_wrapper').offsetHeight + parseInt(window.getComputedStyle(document.getElementsByTagName('body')[0]).getPropertyValue('margin-top'))  + parseInt(window.getComputedStyle(document.getElementsByTagName('body')[0]).getPropertyValue('margin-bottom'))"];
//    float height = [height_str floatValue];
//    //再次设置WebView高度（点）
//    webView.frame = CGRectMake(15, 10, kScreenWidth - 30, height);
//
//    //下面这两行是去掉不必要的webview效果的(选中,放大镜)
//    [webView stringByEvaluatingJavaScriptFromString:@"document.documentElement.style.webkitUserSelect='none';"];
//
//    [webView stringByEvaluatingJavaScriptFromString:@"document.documentElement.style.webkitTouchCallout='none';"];
    
}
/* 页面加载失败 */
- (void)webView:(WKWebView *)webView didFailProvisionalNavigation:(WKNavigation *)navigation{
    [[UIApplication sharedApplication].delegate.window makeToast:@"页面加载失败" duration:1.0 position:CSToastPositionCenter];
    [SVProgressHUD dismiss];
}
/* 在发送请求之前，决定是否跳转 */
- (void)webView:(WKWebView *)webView decidePolicyForNavigationAction:(WKNavigationAction *)navigationAction decisionHandler:(void (^)(WKNavigationActionPolicy))decisionHandler{
    //允许跳转
    decisionHandler(WKNavigationActionPolicyAllow);
    //不允许跳转
    //decisionHandler(WKNavigationActionPolicyCancel);
}
/* 在收到响应后，决定是否跳转 */
- (void)webView:(WKWebView *)webView decidePolicyForNavigationResponse:(WKNavigationResponse *)navigationResponse decisionHandler:(void (^)(WKNavigationResponsePolicy))decisionHandler{
    
    NSLog(@"%@",navigationResponse.response.URL.absoluteString);
    //允许跳转
    decisionHandler(WKNavigationResponsePolicyAllow);
    //不允许跳转
    //decisionHandler(WKNavigationResponsePolicyCancel);
}
//监听方法
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
{

    if ([keyPath isEqualToString:@"contentSize"]) {

        CGSize fitSize = [_myWebView sizeThatFits:CGSizeZero];
        //        NSLog(@"webview fitSize:%@",NSStringFromCGSize(fitSize));
        CGRect rect = self.myWebView.frame;
        rect.size.width = fitSize.width;
        rect.size.height = fitSize.height;
        self.myWebView.frame = rect;


    }
}
- (void)setModel:(TypeDetailModel *)model{
    self.titileLab.text = model.title;
    self.timeLab.text = [NSString stringWithFormat:@"发布日期:%@",[ToolUtil getTimeWithStamp:model.update_time]];
    NSString *result = [NSString stringWithFormat:@"<%@ %@",@"img",@"style='display: block; max-width: 100%;'"];
    NSString*contentStr = model.content;
    
    contentStr = [contentStr stringByReplacingOccurrencesOfString:@"
%@
", contentStr];
    
    //修改图片大小
    NSString *re_imgSize = [NSString stringWithFormat:@"",kScreenWidth - 60];
    
    NSString *htmlcontent = [NSString stringWithFormat:@"
%@
%@",kScreenWidth-30,htmlStr,re_imgSize];
    [self.myWebView loadHTMLString:htmlcontent baseURL:nil];
    
    
}
//-(void)layoutSubviews
//{
//    [super layoutSubviews];
//}
//这里别忘了在dealloc理移除监听
- (void)dealloc {
    NSLog(@"webView ---------dealloc");
    [self.myWebView.scrollView removeObserver:self
                                 forKeyPath:@"contentSize" context:nil];
}




@end

ArticalDetailCell.h

//
//  ArticalDetailCell.h
//  BlockChainNews
//
//  Created by zsm on 2018/5/30.
//  Copyright © 2018年 XinHuoKeJi. All rights reserved.
//

#import 
#import "TypeDetailModel.h"
#import "UIWebView+isLoading.h"
#import "MyWK.h"
typedef void(^WebViewHeightChangedBlock)(float height);
@interface ArticalDetailCell : UITableViewCell
@property (weak, nonatomic) IBOutlet MyWK *myWebView;

//@property (weak, nonatomic) IBOutlet UIWebView *webView;
@property (nonatomic, strong) TypeDetailModel *model;
@property (nonatomic, strong) WebViewHeightChangedBlock webViewHeightChanged;

@end

视图控制器中使用

//MARK:-- 适配iOS10  加载wkwebview 底部留白 计算高度不准确
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
    
    if (self.tableView == scrollView) {
        
        for (UIView *cell in self.tableView.visibleCells) {
            
            if ([cell isKindOfClass:[ArticalDetailCell class]]) {
                
                [((ArticalDetailCell *)cell).myWebView setNeedsLayout];
                
            }
            
        }
        
    }
    
}

cellForRow中使用

ArticalDetailCell * cell = [tableView dequeueReusableCellWithIdentifier:reuseid forIndexPath:indexPath];
        if (self.model) {
            [cell setModel:self.model];
            
            cell.webViewHeightChanged = ^(float height){
                //MARK:--计算webview高度
                BOOL needReload = NO;
                if(self.webViewHeight == 0 ) needReload=YES;
                self.webViewHeight = height + 30;
                
                if (needReload) {
//                    needReload = NO;
                    [self.tableView reloadData];
                    DLog(@"callback --------webViewheight  %d",height);
                }
            };
        }
        return cell;