js与native交互
UIWebView
Native调用JS,使用
stringByEvaluatingJavaScriptFromString来解释执行js脚本。
//script即为要执行的js方法名称
- (NSString *)stringByEvaluatingJavaScriptFromString:(NSString *)script;
PS：苹果推荐iOS8之后的app使用WKWebView来代替UIWebView，同时也使用方法 evaluateJavaScript:completionHandler:来替代stringByEvaluatingJavaScriptFromString，因为会一直等待stringByEvaluatingJavaScriptFromString方法执行完毕
JS调用Native，需要通过UIWebView拦截跳转请求并判断请求头是否是协商好的协议头来判断是否是JS发起调用Native的请求。
- webView:shouldStartLoadWithRequest:navigationType:
function callNative{
var url = ”callNative://nslogHelloWord“
window.location.href = url;
}
- (BOOL)webView:(UIWebView*)webView shouldStartLoadWithRequest:(NSURLRequest*)request navigationType:(UIWebViewNavigationType)navigationType{
//callNative 为约定好的协议头，如果是，则页面不进行跳转
if ([request.URL.scheme isEqualToString:@"callNative"]) {
NSlog(@"Hello World");
return NO;
}
//不是自定义协议头，跳转页面
return YES;
}
WKWebView
苹果自iOS8、OS X 10.10推荐使用WKWebView来代替原先的UIWebView，WKWebView拥有更快的加载速度和性能，更低的内存占用，同时更细致的代理分类来满足不同需要的调用。
Native调用JS,使用方法evaluateJavaScript:completionHandler:来解释执行脚本。
//javaScriptString要执行的js方法
//completionHandler执行结束回调或者发生错误时回调
- (void)evaluateJavaScript:(NSString *)javaScriptString completionHandler:(void (^)(id, NSError *error))completionHandler;
JS调用Native，通过代理WKScriptMessageHandler来实现调用。
#import "WKWVController.h"
#import <WebKit/WebKit.h>
@interface WKWVController ()<WKUIDelegate,WKScriptMessageHandler>
@property (strong, nonatomic) WKWebView *webView;
@end
@implementation WKWVController
- (void)viewDidLoad {
[super viewDidLoad];
// js配置
WKUserContentController *userContentController = [[WKUserContentController alloc] init];
//监听方法名
[userContentController addScriptMessageHandler:self name:@"jsCallOC"];
// WKWebView的配置
WKWebViewConfiguration *configuration = [[WKWebViewConfiguration alloc] init];
configuration.userContentController = userContentController;
// 显示WKWebView
_webView = [[WKWebView alloc] initWithFrame:[UIScreen mainScreen].bounds configuration:configuration];
_webView.UIDelegate = self; // 设置WKUIDelegate代理
[self.view addSubview:_webView];
NSURL *url = [[NSBundle mainBundle] URLForResource:@"index" withExtension:@"html"];
NSURLRequest *urlRequest = [NSURLRequest requestWithURL:url];
[_webView loadRequest:urlRequest];
}
// WKScriptMessageHandler protocol?
- (void)userContentController:(WKUserContentController *)userContentController
didReceiveScriptMessage:(WKScriptMessage *)message
{
NSLog(@"方法名:%@", message.name);
NSLog(@"参数:%@", message.body);
// 方法名
NSString *methods = [NSString stringWithFormat:@"%@", message.name];
SEL selector = NSSelectorFromString(methods);
// 调用方法
if ([self respondsToSelector:selector]) {
[self performSelector:selector withObject:message.body];
} else {
NSLog(@"未实行方法：%@", methods);
}
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
}
- (void)jsCallOC{
[self.webView evaluateJavaScript:@"wkNativeCallJS('嘿嘿')" completionHandler:^(id _Nullable data, NSError * _Nullable error) {
NSLog(@"我执行完毕");
}];
}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>网页</title>
</head>
<body>
<button onclick="wkWebViewTestClick()" style="height: 100px; 200px;">点我调用native方法</button>
function wkNativeCallJS(info){
//wkwebview 不直接使用js的alert 显示不了
//http://stackoverflow.com/questions/34185339/wkwebview-javascript-confirm-and-alert-not-working
console.log(info);
}
function wkWebViewTestClick(){
// 复杂数据
var list = [1,2,3];
var dict = {"name":"阳君", "qq":"937447974"};
// JS通知WKWebView，jsCallOC即为在controller中注册的方法名称
window.webkit.messageHandlers.jsCallOC.postMessage(dict);
}
</script>
</body>
</html>
JavaScriptCore方式相互调用
在iOS7.0中苹果公司增加了JS利器JavaScriptCore框架，JavaScriptCore提供了很多灵活的本地OC与JS的交互方式，通过JSContext和JSValue来完成的，JSContext是一个WebView中js代码运行环境，js可以通过JSContext以block和通过继承JSExport代理，自定义实现代理方法。
#import "WVController.h"
#import <JavaScriptCore/JavaScriptCore.h>
@protocol JSObjcDelegate <JSExport>
-(void)logInfo:(NSString*)info;
@end
@interface WVController ()<JSObjcDelegate>
@property (weak, nonatomic) IBOutlet UIWebView *wv;
@property (nonatomic, strong) JSContext *jsContext;
@end
@implementation WVController
- (void)viewDidLoad {
[super viewDidLoad];
NSString* path = [[NSBundle mainBundle]pathForResource:@"index" ofType:@"html"];
NSURL* url = [NSURL URLWithString:path];
NSURLRequest* request = [NSURLRequest requestWithURL:url];
[self.wv loadRequest:request];
}
//oc调用js
- (IBAction)callJSMethod:(id)sender {
[self.wv stringByEvaluatingJavaScriptFromString:@"wvNativeCallJS()"];
}
//使用url拦截
-(BOOL)webView:(UIWebView *)webView shouldStartLoadWithRequest:(NSURLRequest *)request navigationType:(UIWebViewNavigationType)navigationType{
if ([request.URL.scheme isEqualToString:@"callnative"]) {
NSLog(@"hello world");
return false;
}
return true;
}
- (void)webViewDidFinishLoad:(UIWebView *)webView {
//获取上下文对象
self.jsContext = [webView valueForKeyPath:@"documentView.webView.mainFrame.javaScriptContext"];
self.jsContext[@"Objc"] = self;
self.jsContext.exceptionHandler = ^(JSContext *context, JSValue *exceptionValue) {
context.exception = exceptionValue;
NSLog(@"异常信息：%@", exceptionValue);
};
//直接使用block方式执行oc方法
self.jsContext[@"logHello"] = ^(){
NSLog(@"hello");
};
}
//使用代理接口方式执行native方法
-(void)logInfo:(NSString *)info{
NSLog(@"js传来的参数%@",info);
JSValue* callback = self.jsContext[@"wvNativeCallJS"];
[callback callWithArguments:nil];
}
@end
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>网页</title>
</head>
<body>
//1
<button onclick="Objc.logInfo('哈哈')" style="height: 100px; 200px;">点我调用native方法</button>
//2
<!-- <button onclick="logHello()" style="height: 100px; 200px;">点我调用native方法</button>-->
<script type="text/javascript">
function wvNativeCallJS(){
alert("wvController");
}
</script>
</body>
</html>
DEMO：下载Demo
参考：