iOS:在OC中调用JS脚本
示例一：在webView中调用js脚本进行搜索
1.首先导入JavaScriptCore.framework这个框架
2.创建webView、设置代理、请求手机端百度
#import "ViewController.h"
#import <JavaScriptCore/JavaScriptCore.h>
#define SCREEN_WIDTH [UIScreen mainScreen].bounds.size.width
#define SCREEN_HEIGHT [UIScreen mainScreen].bounds.size.height
@interface ViewController ()<UIWebViewDelegate>
@property (strong,nonatomic)UIWebView *webView;
@property (assign,nonatomic)BOOL isFirstLoadWeb;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
self.webView = [[UIWebView alloc]initWithFrame:self.view.bounds];
self.webView.scalesPageToFit = YES;
self.webView.backgroundColor = [UIColor clearColor];
self.webView.delegate = self;
[self.view addSubview:self.webView];
NSURL *URL = [NSURL URLWithString:@"http://m.baidu.com"];
NSURLRequest *request = [[NSURLRequest alloc]initWithURL:URL];
[self.webView loadRequest:request];
}
3.通过代理方法,在里面调用自定义的JS脚本
-(void)webViewDidFinishLoad:(UIWebView *)webView{
//程序会一直调用该方法,所以判断若是第一次加载后使用我们自定义的js,此后不再调用JS,否则会出现网页抖动现象
if (!_isFirstLoadWeb) {
_isFirstLoadWeb = YES;
//获取当前页面的url
NSString *url = [webView stringByEvaluatingJavaScriptFromString:@"document.location.href"];
//获取页面的title
NSString *title = [webView stringByEvaluatingJavaScriptFromString:@"document.title"];
NSLog(@"%@----%@",url,title);
//给webView添加一个自定义的JavaScript
[webView stringByEvaluatingJavaScriptFromString:@"var script = document.createElement('script');"
"script.type = 'text/javascript';"
"script.text = \"function myFuncation(){"
"var field = document.getElementsByName('word')[0];"
"field.value = '夏先森的博客园';"
"document.forms[0].submit();"
"}\";"
"document.getElementsByTagName('head')[0].appendChild(script);"];
//开始调用自定义的JavaScript
[webView stringByEvaluatingJavaScriptFromString:@"myFuncation();"];
}else{
return;
}
}
@end
演示截图如下：
2016-04-18 21:37:24.670 OC调用JS[7568:356964] https://m.baidu.com/----百度一下
示例二：通过滑动条动态改变网页中字体的大小
1.首先导入JavaScriptCore.framework这个框架
2.创建webView、设置代理、请求手机端百度
#import "ViewController.h"
#import <JavaScriptCore/JavaScriptCore.h>
#define SCREEN_WIDTH [UIScreen mainScreen].bounds.size.width
#define SCREEN_HEIGHT [UIScreen mainScreen].bounds.size.height
@interface ViewController ()<UIWebViewDelegate>
@property (strong,nonatomic)UIWebView *webView;
@property (strong,nonatomic)UIActivityIndicatorView *activityIndicator;
@property (strong,nonatomic)UISlider *slider;
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
//1.创建slider
_slider = [[UISlider alloc]initWithFrame:CGRectMake(10, 40, SCREEN_WIDTH-20, 20)];
[_slider addTarget:self action:@selector(SliderChanged) forControlEvents:UIControlEventValueChanged];
_slider.maximumValue = 1000.0f;
_slider.minimumValue = 10.0f;
_slider.value = 10.0f;
[self.view addSubview:_slider];
//2.创建webView
self.webView = [[UIWebView alloc]initWithFrame:CGRectMake(0, 80, SCREEN_WIDTH, SCREEN_HEIGHT-80)];
self.webView.scalesPageToFit = YES;
self.webView.backgroundColor = [UIColor clearColor];
self.webView.delegate = self;
[self.view addSubview:self.webView];
NSURL *URL = [NSURL URLWithString:@"http://m.baidu.com"];
NSURLRequest *request = [[NSURLRequest alloc]initWithURL:URL];
[self.webView loadRequest:request];
//3.创建活动指示器
_activityIndicator = [[UIActivityIndicatorView alloc]initWithFrame:CGRectMake(0, 0, 40, 50)];
_activityIndicator.center = self.view.center;
_activityIndicator.backgroundColor = [UIColor grayColor];
_activityIndicator.activityIndicatorViewStyle = UIActivityIndicatorViewStyleWhiteLarge;
[self.view addSubview:_activityIndicator];
}
3.滑动滑动条来改变网页字体大小
-(void)SliderChanged{
NSString *str1 = [NSString stringWithFormat:@"document.getElementsByTagName('body')[0].style.webkitTextSizeAdjust = '%f%%'",_slider.value];
[_webView stringByEvaluatingJavaScriptFromString:str1];
}
@end
演示截图如下：
程序猿神奇的手，每时每刻，这双手都在改变着世界的交互方式！
本文转自当天真遇到现实博客园博客，原文链接：http://www.cnblogs.com/XYQ-208910/p/5405997.html
，如需转载请自行联系原作者
