WKWebView是苹果在iOS 8之后推出的框架,关于它比webview的优势这里就不讲了。主要说一下与JS交互的问题,其实WKWebView已经内置了JS与OC的互调、传值等方法,使用起来也非常方便,下面就来细细的探讨一下以及自己遇到过的坑...
首先来看下WKWebView的初始化相关设置:
一、导入相关头文件、设置相关代理和属性
调用相册楼主用的是: TZImagePickerController框架, 如果你用的系统或其他的,直接替换就行
#import "WebViewController.h"
#import "webkit/webkit.h"
#define WS(weakSelf) __weak __typeof(&*self) weakSelf = self
#define kWidth [UIScreen mainScreen].bounds.size.width
#define kHeight [UIScreen mainScreen].bounds.size.height
@interface WebViewController ()<WKNavigationDelegate,WKScriptMessageHandler,WKUIDelegate,TZImagePickerControllerDelegate,UIImagePickerControllerDelegate, UINavigationControllerDelegate>
@property(nonatomic,strong)WKWebView *webView;
@property (nonatomic, strong) UIProgressView *progressView; //进度条加载
@property (nonatomic, strong) NSMutableArray *imgArray;// 图片数组
@property (nonatomic,strong)WKWebViewConfiguration *configuration;
@end
二、WKWebView初始化
- (void)viewDidLoad {
[super viewDidLoad];
// 配置网页的配置文件
WKWebViewConfiguration *configuration = [[WKWebViewConfiguration alloc] init];
WKPreferences *preference = [[WKPreferences alloc]init];
configuration.preferences = preference;
configuration.selectionGranularity = YES; //允许与网页交互
// webView初始化
self.webView = [[WKWebView alloc] initWithFrame:CGRectMake(0, 0, kWidth, kHeight) configuration:configuration];
self.view.backgroundColor = [UIColor whiteColor];
self.webView.UIDelegate = self;
self.webView.navigationDelegate = self;
_webView.allowsBackForwardNavigationGestures = YES; //二级网页是否可以左划返回
// 楼主这里隐藏了原生导航栏,加载的 H5导航栏,下拉不允许导航栏跟着下拉,设置弹簧效果为NO即可
_webView.scrollView.bounces = NO;
[self.webView loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:self.urlStr]]];
[self.view addSubview:self.webView];
}
接下来才是重点!!!
一、JS调OC,JS给OC传值
// JS调OC,需要 H5端统一如下写法,方法名就是交互的名称,数据就是JS给OC传的值
window.webkit.messageHandlers.<方法名>.postMessage(<数据>)
注意:
楼主遇到的第一个坑:如果JS给OC传值为空,必须写成: postMessage(null),如果什么都不写,方法是调不通的。
1、在viewWillAppear中配置, addScriptMessageHandler name: "这里就是JS的方法,方法名必须统一"
-(void)viewWillAppear:(BOOL)animated{
[super viewWillAppear:animated];
#pragma mark ======= JS事件 ========
//因为楼主的导航栏是隐藏了的,显示的是H5的导航栏,所以要调用返回按钮到主页面
[self.webView.configuration.userContentController addScriptMessageHandler:self name:@"back"];
//拍照
[self.webView.configuration.userContentController addScriptMessageHandler:self name:@"camera"];
//从相册选取
[self.webView.configuration.userContentController addScriptMessageHandler:self name:@"album"];
//H5请求接口时,调用原生的指示器加载
[self.webView.configuration.userContentController addScriptMessageHandler:self name:@"loadIndicator"];
//接口请求完成,隐藏指示器
[self.webView.configuration.userContentController addScriptMessageHandler:self name:@"hiddenIndicator"];
}
楼主遇到的第二个坑:配置完后必须在viewWillDisappear
中 remove,否则会造成循环引用,导致crash
- (void)viewWillDisappear:(BOOL)animated
{
[super viewWillDisappear:animated];
// 这里要记得移除handlers
[self.webView.configuration.userContentController removeScriptMessageHandlerForName:@"back"];
[self.webView.configuration.userContentController removeScriptMessageHandlerForName:@"camera"];
[self.webView.configuration.userContentController removeScriptMessageHandlerForName:@"album"];
[self.webView.configuration.userContentController removeScriptMessageHandlerForName:@"loadIndicator"];
[self.webView.configuration.userContentController removeScriptMessageHandlerForName:@"hiddenIndicator"];
}
2、实现 WKScriptMessageHandler 协议
//WKScriptMessageHandler协议方法
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message {
// message.body 即为JS向OC传的值
id body = message.body;
NSLog(@"=== %@", body);
if ([message.name isEqualToString:@"back"]) {
//返回到首页
[self.navigationController popViewControllerAnimated:YES];
}if ([message.name isEqualToString:@"camera"]) {
//拍照
[self takePhotos];
} if ([message.name isEqualToString:@"album"]) {
//从相册选取
[self localPhotos];
}if ([message.name isEqualToString:@"loadIndicator"]) {
//加载指示器
[SVProgressHUD show];
}if ([message.name isEqualToString:@"hiddenIndicator"]) {
//隐藏指示器
[SVProgressHUD dismiss];
}
}
以上就是JS调OC,JS向OC传值...
二、OC调JS,OC向JS传值
实现该方法即可:
[webView evaluateJavaScript:<> completionHandler:^(id _Nullable response, NSError * _Nullable error){}];
楼主这里举三个例子:
1: webview加载完成前,将用户信息传给js
2: webview加载完成,将相关信息传给js
3: 调用相册或相机时,将选择的图片请求后台接口,后台返回图片地址,将该地址回传给H5,H5将图片显示到页面上
第一个例子: webView加载完成前传值
因为 evaluateJavaScript
方法默认是在加载完成后调用,所以直接在页面开始加载中调用是传不过去的,这个时候怎么办呢?我们可以让js端写两个方法, 第一个方法是js端开始向oc端发起信息需求的方法名,当oc端收到该方法名的时候,就去调用js端第二个获取传值的方法,把信息传递过去。
先让JS端写个方法调OC,OC实现方法后在这个方法内部给JS传值
-(void)viewWillAppear:(BOOL)animated{
[super viewWillAppear:animated];
//发起信息需求
[self.webView.configuration.userContentController addScriptMessageHandler:self name:@"getUserInfo"];
在WKScriptMessageHandler协议中,实现该方法,然后在方法内部给JS传值
- (void)userContentController:(WKUserContentController *)userContentController didReceiveScriptMessage:(WKScriptMessage *)message {
id body = message.body;
NSLog(@"=== %@", body);
if ([message.name isEqualToString:@"getUserInfo"]) {
NSLog(@"getUserInfo");
//在这里给JS传值
NSDictionary *dict = @{@"id":@"123", @"name":@"lisi"};
//转为json
NSData *data = [NSJSONSerialization dataWithJSONObject:dict options:(NSJSONWritingPrettyPrinted) error:nil];
NSString *jsonStr = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(@"jsonStr == %@",jsonStr);
//给js传值,获取用户信息
NSString *inputValueJS = [NSString stringWithFormat:@"getCurrentUser('%@')", jsonStr];
[webView evaluateJavaScript:inputValueJS completionHandler:^(id _Nullable response, NSError * _Nullable error) {
//打印如果error为null,表示已调通
NSLog(@"value: %@ error: %@", response, error);
}];
}
}
注意:以上就是在Webview加载完成前传值,如果打印没报错,证明传参成功,如果web端没收到,让他把获取到值的方法写到页面中即可。
第二个例子: webView加载完成,传值给js
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation{
NSDictionary *dict = @{@"id":@"123", @"name":@"lisi"};
//转为json
NSData *data = [NSJSONSerialization dataWithJSONObject:dict options:(NSJSONWritingPrettyPrinted) error:nil];
NSString *jsonStr = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
NSLog(@"jsonStr == %@",jsonStr);
//给js传值,获取用户信息
NSString *inputValueJS = [NSString stringWithFormat:@"getCurrentUser('%@')", jsonStr];
[webView evaluateJavaScript:inputValueJS completionHandler:^(id _Nullable response, NSError * _Nullable error) {
//打印如果error都为null,表示已调通
NSLog(@"value: %@ error: %@", response, error);
}];
}
第三个例子: 传图片地址给js,js拿到后显示图片
1:拍照事件
//拍照
- (void)takePhotos{
UIImagePickerControllerSourceType sourceType = UIImagePickerControllerSourceTypeCamera;
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera]) {
UIImagePickerController *picker = [[UIImagePickerController alloc]init];
picker.delegate = self;
picker.allowsEditing = YES;
picker.sourceType = sourceType;
[self.navigationController presentViewController:picker animated:YES completion:^{
NSLog(@"OK");
}];
}
else {
NSLog(@"模拟其中无法打开照相机,请在真机中使用");
}
}
1.1:将拍的照片请求上传图片接口,成功返回图片地址,并传值给H5
// 相机
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info{
[picker dismissViewControllerAnimated:YES completion:^{}];
[self.imgArray removeAllObjects];
UIImage *image = [info objectForKey:UIImagePickerControllerOriginalImage];
[self.imgArray addObject:image];
if (self.imgArray.count) {
//这里开始写请求上传图片接口的代码
//请求成功,获取返回的图片地址,如果是数组,将数组转换为字符串
NSString *urlStr = [[数组] componentsJoinedByString:@""];
// 然后向js传图片地址:
NSString *inputValue = [NSString stringWithFormat:@"getPhotoCallback('%@')",urlStr];
[self.webView evaluateJavaScript:inputValue completionHandler:^(id _Nullable response, NSError * _Nullable error) {
NSLog(@"value图片: %@ error: %@", response, error);
}];
}
}
2: 从相册中选取照片
#pragma mark TZImagePickerControllerDelegate
#pragma mark -- 从相册中选择照片
-(void)localPhotos{
TZImagePickerController *imagePickerVc = [[TZImagePickerController alloc] initWithMaxImagesCount:1 delegate:self];
[self.navigationController presentViewController:imagePickerVc animated:YES completion:nil];
}
/// 用户点击了取消
- (void)imagePickerControllerDidCancel:(TZImagePickerController *)picker {
[self dismissViewControllerAnimated:YES completion:nil];
}
2.2:将相册中选取的照片请求上传图片接口,成功返回图片地址,并传值给H5
// 相册
/// 用户选择好了图片,如果assets非空,则用户选择了原图。
- (void)imagePickerController:(TZImagePickerController *)picker didFinishPickingPhotos:(NSArray *)photos sourceAssets:(NSArray *)assets{
[self.imgArray removeAllObjects];
for (int i = 0; i < photos.count; i++) {
UIImage *image = photos[i];
[self.imgArray addObject:image];
}
if (self.imgArray.count) {
//这里开始写请求上传图片接口的代码
//请求成功,获取返回的图片地址,如果是数组,将数组转换为字符串
NSString *urlStr = [[数组] componentsJoinedByString:@""];
// 然后向js传图片地址:
NSString *inputValue = [NSString stringWithFormat:@"getPhotoCallback('%@')",urlStr];
[self.webView evaluateJavaScript:inputValue completionHandler:^(id _Nullable response, NSError * _Nullable error) {
NSLog(@"value图片: %@ error: %@", response, error);
}];
}
}
注意: getPhotoCallback
即为调用的方法名,后面传值格式必须为:('')
, 这里遇到了第三个坑,如果方法名写为: 名称.名称 (例如:hello. getPhotoCallback),这种是调不通的,可以写成hello_getPhotoCallback的形式,一般的话最好还是定义一个完整的名称。
刚开始这个问题卡了比较久,一直调不通,在此记录一下.....
以上就是OC调JS,OC给JS传值的分享!!!
最后分享一下:
WKWebView进度条加载....
在 viewDidLoad
中注册进度条监听
- (void)viewDidLoad {
[super viewDidLoad];
//添加进度条监听
[self.webView addObserver:self forKeyPath:@"estimatedProgress" options:NSKeyValueObservingOptionNew context:nil];
}
开始加载网页
- (void)webView:(WKWebView *)webView didStartProvisionalNavigation:(WKNavigation *)navigation
{
//显示
self.progressView.hidden = NO;
self.progressView.transform = CGAffineTransformMakeScale(1.0f, 1.5f);
[self.view bringSubviewToFront:self.progressView];
}
加载完成
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation{
//隐藏
self.progressView.hidden = YES;
}
加载失败
// 页面加载失败时调用
- (void)webView:(WKWebView *)webView didFailProvisionalNavigation:(WKNavigation *)navigation withError:(NSError *)error
{
self.progressView.hidden = YES;
}
页面跳转失败
//页面跳转失败时调用
- (void)webView:(WKWebView *)webView didFailNavigation:(WKNavigation *)navigation withError:(NSError *)error
{
if(error.code==NSURLErrorCancelled)
{
[self webView:webView didFinishNavigation:navigation];
}else{
self.progressView.hidden = YES;
}
}
progressView懒加载
- (UIProgressView *)progressView
{
if (!_progressView)
{
_progressView = [[UIProgressView alloc] initWithFrame:CGRectMake(0, Height_StatusBar, kWidth, 2)];
_progressView.backgroundColor = [UIColor blueColor];
_progressView.transform = CGAffineTransformMakeScale(1.0f, 1.5f);
_progressView.progressTintColor = [UIColor blueColor];
[self.view addSubview:self.progressView];
}
return _progressView;
}
添加监听观察者
- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary<NSString *,id> *)change context:(void *)context
{
if ([keyPath isEqualToString:@"estimatedProgress"])
{
self.progressView.progress = self.webView.estimatedProgress;
if (self.progressView.progress == 1)
{
WS(weakSelf);
[UIView animateWithDuration:0.25f delay:0.3f options:UIViewAnimationOptionCurveEaseOut animations:^
{
weakSelf.progressView.transform = CGAffineTransformMakeScale(1.0f, 1.4f);
}
completion:^(BOOL finished)
{
weakSelf.progressView.hidden = YES;
}];
}
}
}
最后别忘记 removeObserver
-(void)dealloc{
[self.webView removeObserver:self forKeyPath:@"estimatedProgress"];
}