今天在将UIWebView替换成WkWebView的过程中遇到一点小问题，就是加载后台由文本编辑器生成的HTML语言是字体大小出现了问题，显得很小，并且很紧凑。
后台给我们的标签字符串：
NSString *htmlContent = @"<body style='background-color:#fef5f3;margin:0.2rem 0;line-height:1rem;font-size:0.75rem;color:#61310a;padding: 0.5rem 0.8rem 0;'><p style=\"white-space: normal; text-indent: 2em; text-align: justify; line-height: 1.5em;\"><span style=\"font-family: 微软雅黑, \" microsoft=\"\" font-size:=\"\">优惠券领取规则</span></p><p style=\"white-space: normal; text-indent: 2em; text-align: justify; line-height: 1.5em;\"><span style=\"font-family: 微软雅黑, \" microsoft=\"\" font-size:=\"\">1、VIP优惠券每月可领，只能领取自身VIP等级相对应的优惠券；</span></p><p style=\"white-space: normal; text-indent: 2em; text-align: justify; line-height: 1.5em;\"><span style=\"font-family: 微软雅黑, \" microsoft=\"\" font-size:=\"\">2、优惠券请在有效期内使用，逾期自动失效；</span></p><p style=\"white-space: normal; text-indent: 2em; text-align: justify; line-height: 1.5em;\"><span style=\"font-family: 微软雅黑, \" microsoft=\"\" font-size:=\"\">3、退出VIP会员后，不再享受每月领券权益。</span></p><p style=\"white-space: normal; text-indent: 2em; text-align: justify; line-height: 1.5em;\"><span style=\"font-family: 微软雅黑, \" microsoft=\"\" font-size:=\"\">优惠券使用规则</span></p><p style=\"white-space: normal; text-indent: 2em; text-align: justify; line-height: 1.5em;\"><span style=\"font-family: 微软雅黑, \" microsoft=\"\" font-size:=\"\">1、只能使用对应等级的优惠券，使用后可获得相应奖励或减免；</span></p><p style=\"white-space: normal; text-indent: 2em; text-align: justify; line-height: 1.5em;\"><span style=\"font-family: 微软雅黑, \" microsoft=\"\" font-size:=\"\">2、优惠券限本人使用，不可转赠他人；</span></p><p style=\"white-space: normal; text-indent: 2em; text-align: justify; line-height: 1.5em;\"><span style=\"font-family: 微软雅黑, \" microsoft=\"\" font-size:=\"\">3、优惠券请在有效期内使用，逾期自动失效。</span></p><p><br/></p></body>";
WKWebView *webView = [[WKWebView alloc] init];
//内容少于webView高度的时候不垂直滚动
webView.scrollView.alwaysBounceVertical = NO;
//适配iOS 11
[Toolkit setContentInsetAdjustmentBehaviorNever4ScrollView:webView.scrollView];
[webView loadHTMLString:htmlContent baseURL:nil];
[[NSURLCache sharedURLCache] removeAllCachedResponses];//删除web缓存
[self.view addSubview:self.topLine];
[self.view addSubview:self.webView];
self.webView = webView;
[self.view addSubview:self.progressView];
//获取标题和进度条
[self.webView addObserver:self forKeyPath:@"title" options:NSKeyValueObservingOptionNew context:nil];
[self.webView addObserver:self forKeyPath:@"estimatedProgress" options:NSKeyValueObservingOptionNew| NSKeyValueObservingOptionOld context:nil];
之前UIWebView加载的情况：
UIWebView.png
还不错。
替换成WkWebView的展示：
WkWebView.png
绝对不能忍，字体变得太小了。
首先，出现这个问题的根本原因是标签中缺少meta标签，最简单的办法是让后台给我加上，将完整的标签格式返回给我们。但是，最简单的办法往往也是最难实现的，由于后台存储的是文本编辑器自动生成的标签语言，所以后台往往是从数据库中读取之后直接返回给我们了，我们的后台还不错，起码给我加了body标签，O(∩_∩)O哈哈~
啰嗦太多了，说一下解决方案吧，大体上有四种：
一、使用UIWebView
我&*#$%$%%，我换了干啥来着，当我没说。
一、拼接（上面第一种不算）
//我们在header标签里加上meta标签（大小关键是minimum-scale=1.1，数值越大，字体越大）
NSString *htmlHeader = @"<header><meta name='viewport' content='width=device-width, initial-scale=1.0, maximum-scale=2.0, minimum-scale=1.1, user-scalable=no'></header>";
//
[htmlHeader stringByAppendingString:htmlContent];
[self.webView loadHTMLString:htmlContent baseURL:nil];
加载效果:
拼接效果.png
字体效果马马虎虎还可以，等等，怎么可以左右滚和上下滚了？我也不知道。未知的都是可怕的，方案pass掉。
二、在webView加载完毕的代理方法里通过调用JS方法改变
//代理
webView.navigationDelegate = self;
//MARK:-UINavigationDelegate
-(void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation{
//修改字体大小 240%
[ webView evaluateJavaScript:@"document.getElementsByTagName('body')[0].style.webkitTextSizeAdjust= '240%'"completionHandler:nil];
//修改字体颜色 #222222
[ webView evaluateJavaScript:@"document.getElementsByTagName('body')[0].style.webkitTextFillColor= '#222222'"completionHandler:nil];
}
效果：
代理改变.png
字体变大了没错，颜色也改变了，不过这间距也太大了！！！而且网路慢的话还有字体本来小，加载完成变大的问题。
就当熟悉一下evaluateJavaScript方法了，改变颜色还是可以滴，再次pass。
三、通过WKUserScript注入JavaScript脚本和WKPreferences设置字体大小
//js脚本
NSString *jScript = @"var meta = document.createElement('meta'); meta.setAttribute('name', 'viewport'); meta.setAttribute('content', 'width=device-width'); document.getElementsByTagName('head')[0].appendChild(meta);";
//注入
WKUserScript *wkUScript = [[WKUserScript alloc] initWithSource:jScript injectionTime:WKUserScriptInjectionTimeAtDocumentEnd forMainFrameOnly:YES];
WKUserContentController *wkUController = [[WKUserContentController alloc] init];
[wkUController addUserScript:wkUScript];
//配置对象
WKWebViewConfiguration *wkWebConfig = [[WKWebViewConfiguration alloc] init];
wkWebConfig.userContentController = wkUController;
//改变初始化方法
WKWebView *webView = [[WKWebView alloc] initWithFrame:CGRectZero configuration:wkWebConfig];
效果：
WKWebView脚本注入.png
效果不错，跟UIWebView加载效果一样，提上裤子走人！
忘了说字体设置了。。。。。。。。。(不脱了！就一会儿)
// 创建设置对象
WKPreferences *preference = [[WKPreferences alloc]init];
// 设置字体大小(最小的字体大小)
preference.minimumFontSize = 15;
// 设置偏好设置对象
wkWebConfig.preferences = preference;
效果：
字体设置.png
满足了。。。
我的代码：
#import "RequestHTMLViewController.h"
#import <WebKit/WebKit.h>
@interface RequestHTMLViewController ()
@property(nonatomic, strong) WKWebView *webView;
@property (strong, nonatomic) UIProgressView *progressView;//进度条
@property (nonatomic,strong) UIView *topLine;
@end
@implementation RequestHTMLViewController
//MARK:-lazy load
-(UIView *)topLine{
if (!_topLine) {
UIView *lineV = [UIView new];
lineV.backgroundColor = [Toolkit getColor:hex_cccccc];
_topLine = lineV;
}
return _topLine;
}
- (UIProgressView *)progressView
{
if(!_progressView)
{
UIProgressView *progressV = [UIProgressView new];
progressV.tintColor = [Toolkit getColor:hex_red_color];
progressV.trackTintColor = [UIColor whiteColor];
_progressView = progressV;
}
return _progressView;
}
-(WKWebView *)webView{
if (!_webView) {
NSString *jScript = @"var meta = document.createElement('meta'); meta.setAttribute('name', 'viewport'); meta.setAttribute('content', 'width=device-width'); document.getElementsByTagName('head')[0].appendChild(meta);";
WKUserScript *wkUScript = [[WKUserScript alloc] initWithSource:jScript injectionTime:WKUserScriptInjectionTimeAtDocumentEnd forMainFrameOnly:YES];
WKUserContentController *wkUController = [[WKUserContentController alloc] init];
[wkUController addUserScript:wkUScript];
WKWebViewConfiguration *wkWebConfig = [[WKWebViewConfiguration alloc] init];
wkWebConfig.userContentController = wkUController;
// 创建设置对象
WKPreferences *preference = [[WKPreferences alloc]init];
// 设置字体大小(最小的字体大小)
preference.minimumFontSize = 15;
// 设置偏好设置对象
wkWebConfig.preferences = preference;
WKWebView *webView = [[WKWebView alloc] initWithFrame:CGRectZero configuration:wkWebConfig];
webView.scrollView.alwaysBounceVertical = NO;
[Toolkit setContentInsetAdjustmentBehaviorNever4ScrollView:webView.scrollView];
_webView = webView;
}
return _webView;
}
//MARK:-lifecycle
- (void)viewDidLoad {
[super viewDidLoad];
self.view.backgroundColor = [UIColor whiteColor];
_topView.backgroundColor = [Toolkit getColor:hex_red_color];
_lblTitle.text = self.requestTitle;
_lblTitle.textColor = [UIColor whiteColor];
[[NSURLCache sharedURLCache] removeAllCachedResponses];//删除web缓存
[self.view addSubview:self.topLine];
[self.view addSubview:self.webView];
[self.view addSubview:self.progressView];
//获取标题和进度条
[self.webView addObserver:self forKeyPath:@"title" options:NSKeyValueObservingOptionNew context:nil];
[self.webView addObserver:self forKeyPath:@"estimatedProgress" options:NSKeyValueObservingOptionNew| NSKeyValueObservingOptionOld context:nil];
[self makeMasConstraints];
}
-(void)dealloc{
[[NSURLCache sharedURLCache] removeAllCachedResponses];//删除web缓存
[self.webView removeObserver:self forKeyPath:@"title"];
[self.webView removeObserver:self forKeyPath:@"estimatedProgress"];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
}
//MARK:-setter
-(void)setRequestService:(NSString *)requestService{
_requestService = requestService;
[self contentRequest];
}
//MARK:-request
-(void)contentRequest{
if (self.requestService) {
NSDictionary *params = @{ServiceKey:self.requestService};
[[Mall_APIManager sharedManager] JQ_common_requestWithParams:params andBlock:^(id data, NSError *error) {
// NSLog(@"data ====== %@",data);
NSNumber * ret=data[@"ret"];
if ([ret isEqualToNumber:kRequestSuccess]) {
// NSDictionary *contentDic = data[@"data"][@"content"];
NSString *htmlContent = data[@"data"][@"content"];
[self.webView loadHTMLString:htmlContent baseURL:nil];
}else if ([ret isEqualToNumber:kRequestError]){
[SVProgressHUD showInfoWithStatus:data[@"msg"]];
}
}];
}
}
//MARK:-kvo监听
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
if ([keyPath isEqualToString:@"title"] && (object == self.webView)) {
_lblTitle.text = self.webView.title;
} else if ([keyPath isEqual: @"estimatedProgress"] && object == self.webView) {
[self.progressView setAlpha:1.0f];
[self.progressView setProgress:self.webView.estimatedProgress animated:YES];
if(self.webView.estimatedProgress >= 1.0f) {
[UIView animateWithDuration:0.5 delay:0.5 options:UIViewAnimationOptionCurveEaseOut animations:^{
[self.progressView setAlpha:0.0f];
} completion:^(BOOL finished) {
[self.progressView setProgress:0.0f animated:NO];
}];
}
} else {
[super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
}
}
#pragma mark - makeMasConstraints
- (void)makeMasConstraints {
[self.topLine makeConstraints:^(MASConstraintMaker *make) {
make.top.equalTo(_topView.mas_bottom);
make.height.equalTo(@0.5);
make.left.width.equalTo(_topView);
}];
[self.progressView makeConstraints:^(MASConstraintMaker* make){
make.top.equalTo(self.topLine.mas_bottom);
make.left.equalTo(self.view);
make.right.equalTo(self.view);
make.height.equalTo(@1.5);
}];
[self.webView makeConstraints:^(MASConstraintMaker* make){
make.top.equalTo(self.topLine.bottom);
make.bottom.equalTo(self.view);
make.left.equalTo(self.view);
make.right.equalTo(self.view);
}];
}
