Web Front-end
JS Tutorial
Detailed explanation of sample code using JavaScriptCore to realize OC and JS interaction
Detailed explanation of sample code using JavaScriptCore to realize OC and JS interaction
JavaScriptCore is an important part of webkit, mainly parsing JS and provide an execution environment. The following article mainly introduces you to the relevant information about using JavaScriptCore to realize the interaction between OC and JS. The introduction in the article is very detailed. Friends who need it can refer to it. Let’s take a look.
JavascriptCore
JavascriptCore is an important part of webkit. It mainly parses JS and provides an execution environment. After iOS7, Apple launched it on the iPhone platform, which is a great development. It facilitates our operation of js.
First create a webView and read the local html file
NSURL* htmlURL = [[NSBundle mainBundle] URLForResource: @"demo" withExtension: @"html"]; [_webView loadRequest: [NSURLRequest requestWithURL: htmlURL]];
In the demo, we have to implement 4 situations
JS calls OC
JS calls OC and passes parameters
OC calls JS
OC calls JS and passes parameters
The code in the html file is as follows
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script type="text/javascript">
function showAlert(){
alert('OC call JS with no argument');
}
function showAlertWithString(string){
alert(string);
}
function callOCWithArgument() {
jsCallOCWithArgument('参数1 ','参数2 ','参数3');
}
</script>
</head>
<body>
</br>
</br>
</br>
</br>
<form>
<button type='button' onclick='callOC()'>jsCallOC</button>
<button type='button' onclick='callOCWithArgument()'>jsCallOCWithArgument</button>
</form>
</body>
</html>JS calls OC
In webView's proxy method webViewDidFinishLoad
-(void)webViewDidFinishLoad:(UIWebView *)webView
{
_context = [webView valueForKeyPath:@"documentView.webView.mainFrame.javascriptContext"];
weak typeof(self) weakSelf = self;
_context.exceptionHandler = ^(JSContext *context, JSValue *exception) {
weakSelf.context.exception = exception;
};
//js调用OC
_context[@"callOC"] = ^() {
NSArray *args = [JSContext currentArguments];
for (JSValue *jsVal in args) {
NSLog(@"%@", jsVal.toString);
}
dispatch_async(dispatch_get_main_queue(), ^{
UIAlertController *alertView = [UIAlertController alertControllerWithTitle:@"arguments"
message:@"JS Call OC With No Argument" preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction * action = [UIAlertAction actionWithTitle:@"Done" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
}];
[alertView addAction:action];
[weakSelf presentViewController:alertView animated:YES completion:nil];
});
};
_context[@"jsCallOCWithArgument"] = ^() {
NSArray *args = [JSContext currentArguments];
NSMutableString * stirng = [NSMutableString string];
for (JSValue * value in args) {
[stirng appendString:value.toString];
}
dispatch_async(dispatch_get_main_queue(), ^{
UIAlertController *alertView = [UIAlertController alertControllerWithTitle:@"arguments" message:stirng preferredStyle:UIAlertControllerStyleAlert];
UIAlertAction * action = [UIAlertAction actionWithTitle:@"Done" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
}];
[alertView addAction:action];
[weakSelf presentViewController:alertView animated:YES completion:nil];
});
};
}We define a block and save it to the context. In fact, it is converted into a function named callOC in JS. Then we execute this function directly, and what is called is the content in our block.
The passed parameters can be accepted through the [JSContext currentArguments] array, which is the JSValue object.
##OC calls JS
to initialize two Buttons, and implement the following method- (IBAction)callJS:(id)sender {
[_context evaluatescript:@"showAlert()"];
}
- (IBAction)callJSWithArguments:(id)sender {
[_context evaluatescript:@"showAlertWithString('OC call JS with arguments')"];
// [_context[@"showAlertWithString"] callWithArguments:@[@"OC call JS with arguments"]];
}Summary
The above is the detailed content of Detailed explanation of sample code using JavaScriptCore to realize OC and JS interaction. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
1386
52
How to use JS and Baidu Maps to implement map pan function
Nov 21, 2023 am 10:00 AM
How to use JS and Baidu Map to implement map pan function Baidu Map is a widely used map service platform, which is often used in web development to display geographical information, positioning and other functions. This article will introduce how to use JS and Baidu Map API to implement the map pan function, and provide specific code examples. 1. Preparation Before using Baidu Map API, you first need to apply for a developer account on Baidu Map Open Platform (http://lbsyun.baidu.com/) and create an application. Creation completed
Recommended: Excellent JS open source face detection and recognition project
Apr 03, 2024 am 11:55 AM
Face detection and recognition technology is already a relatively mature and widely used technology. Currently, the most widely used Internet application language is JS. Implementing face detection and recognition on the Web front-end has advantages and disadvantages compared to back-end face recognition. Advantages include reducing network interaction and real-time recognition, which greatly shortens user waiting time and improves user experience; disadvantages include: being limited by model size, the accuracy is also limited. How to use js to implement face detection on the web? In order to implement face recognition on the Web, you need to be familiar with related programming languages and technologies, such as JavaScript, HTML, CSS, WebRTC, etc. At the same time, you also need to master relevant computer vision and artificial intelligence technologies. It is worth noting that due to the design of the Web side
How to create a stock candlestick chart using PHP and JS
Dec 17, 2023 am 08:08 AM
How to use PHP and JS to create a stock candle chart. A stock candle chart is a common technical analysis graphic in the stock market. It helps investors understand stocks more intuitively by drawing data such as the opening price, closing price, highest price and lowest price of the stock. price fluctuations. This article will teach you how to create stock candle charts using PHP and JS, with specific code examples. 1. Preparation Before starting, we need to prepare the following environment: 1. A server running PHP 2. A browser that supports HTML5 and Canvas 3
Essential tools for stock analysis: Learn the steps to draw candle charts with PHP and JS
Dec 17, 2023 pm 06:55 PM
Essential tools for stock analysis: Learn the steps to draw candle charts in PHP and JS. Specific code examples are required. With the rapid development of the Internet and technology, stock trading has become one of the important ways for many investors. Stock analysis is an important part of investor decision-making, and candle charts are widely used in technical analysis. Learning how to draw candle charts using PHP and JS will provide investors with more intuitive information to help them make better decisions. A candlestick chart is a technical chart that displays stock prices in the form of candlesticks. It shows the stock price
How to use JS and Baidu Map to implement map click event processing function
Nov 21, 2023 am 11:11 AM
Overview of how to use JS and Baidu Maps to implement map click event processing: In web development, it is often necessary to use map functions to display geographical location and geographical information. Click event processing on the map is a commonly used and important part of the map function. This article will introduce how to use JS and Baidu Map API to implement the click event processing function of the map, and give specific code examples. Steps: Import the API file of Baidu Map. First, import the file of Baidu Map API in the HTML file. This can be achieved through the following code:
How to use JS and Baidu Maps to implement map heat map function
Nov 21, 2023 am 09:33 AM
How to use JS and Baidu Maps to implement the map heat map function Introduction: With the rapid development of the Internet and mobile devices, maps have become a common application scenario. As a visual display method, heat maps can help us understand the distribution of data more intuitively. This article will introduce how to use JS and Baidu Map API to implement the map heat map function, and provide specific code examples. Preparation work: Before starting, you need to prepare the following items: a Baidu developer account, create an application, and obtain the corresponding AP
PHP and JS Development Tips: Master the Method of Drawing Stock Candle Charts
Dec 18, 2023 pm 03:39 PM
With the rapid development of Internet finance, stock investment has become the choice of more and more people. In stock trading, candle charts are a commonly used technical analysis method. It can show the changing trend of stock prices and help investors make more accurate decisions. This article will introduce the development skills of PHP and JS, lead readers to understand how to draw stock candle charts, and provide specific code examples. 1. Understanding Stock Candle Charts Before introducing how to draw stock candle charts, we first need to understand what a candle chart is. Candlestick charts were developed by the Japanese
How to use JS and Baidu Maps to implement map polygon drawing function
Nov 21, 2023 am 10:53 AM
How to use JS and Baidu Maps to implement map polygon drawing function. In modern web development, map applications have become one of the common functions. Drawing polygons on the map can help us mark specific areas for users to view and analyze. This article will introduce how to use JS and Baidu Map API to implement map polygon drawing function, and provide specific code examples. First, we need to introduce Baidu Map API. You can use the following code to import the JavaScript of Baidu Map API in an HTML file
