Reputation: 6158

The font looks like smaller in WKWebView than in UIWebView

I changed UIWebView to WKWebView, however, with the same html, the font in WKWebView looks like smaller than in UIWebView. I don't want this happen, so is there any way to avoid this change?

Upvotes: 74

Answers (8)

matsotaa

Reputation: 123

It's possible to scale the content by applying a zoom to JavaScript directly:

func scaleWebViewTextContent(_ webView: WKWebView, _ multiplier: Double) {
    let jsCode =
    """
    var scale = \(multiplier);
    document.body.style.zoom = scale;
    """
    webView.evaluateJavaScript(jsCode)
}

Upvotes: 0

无夜之星辰

Reputation: 6158

Finally I solved this problem by adding an html string:

For Objective-C:

NSString *headString = @"<head><meta name='viewport' content='width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, user-scalable=no'></head>";
[self.webView loadHTMLString:[headString stringByAppendingString:yourHTMLString] baseURL:nil];

For Swift:

let headString = "<head><meta name='viewport' content='width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, user-scalable=no'></head>"
webView.loadHTMLString(headString + yourHTMLString, baseURL: nil)

What's more,if you want to load url rather than html you can try:

private var isInjected: Bool = false
webView.navigationDelegate = self
// MARK: - WKNavigationDelegate
func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
    if isInjected == true {
        return
    }
    self.isInjected = true
    // get HTML text
    let js = "document.body.outerHTML"
    webView.evaluateJavaScript(js) { (html, error) in
        let headString = "<head><meta name='viewport' content='width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, user-scalable=no'></head>"
        webView.loadHTMLString(headString + (html as! String), baseURL: nil)
    }
    
}

Upvotes: 206

wzso

Reputation: 3885

I fixed this by injecting the JavaScript code provided above in a neat way. Here is the way I instantiate WKWebView.

private func makeWebView() -> WKWebView {
    let config = WKWebViewConfiguration()
    let ctr = WKUserContentController()
    config.userContentController = ctr
    // JavaScript to inject
    let src = """
    document.body.insertAdjacentHTML('beforebegin',"<header><meta
    name='viewport' content='width=device-width, initial-scale=1.0,
    maximum-scale=1.0, minimum-scale=1.0, user-scalable=no'>
    </header>");
    """
    let script = WKUserScript(source: src,
                              injectionTime: .atDocumentStart,
                              forMainFrameOnly: false)
    ctr.addUserScript(script)
    
    let webView = WKWebView(frame: .zero, configuration: config)
    webView.navigationDelegate = self
    webView.uiDelegate = self

    return webView
}

Upvotes: 0

Shahriar Hossain

Reputation: 148

This code work for me:

func fill(_ model:NewsModel){
    let description = "<p>\(model.details) <p>"
    var headerString = "<header><meta name='viewport' content='width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0'></header>"
    headerString.append(description)
    self.detailsTestWebView.loadHTMLString("\(headerString)", baseURL: nil)
}

Upvotes: 1

Berat Cevik

Reputation: 1958

From iOS 14 onward you can achieve this with pageZoom property. For example

webView.pageZoom = 2.0;

will make page content twice as large.

Here's the link for documentation:

https://developer.apple.com/documentation/webkit/wkwebview/3516411-pagezoom

Upvotes: 3

Amr AbdelWahab

Reputation: 115

We can insert Headers into html throght javaScrip insertAdjacentHTML function in WKNavigationDelegate didFinish navigation method

extension HelpScreenViewController: WKNavigationDelegate {
// MARK: - WKNavigationDelegate
public func webView(_ webView: WKWebView, didFinish navigation: WKNavigation!) {
    guard !isInjected else  {
        return
    }
    self.isInjected = true
    let js = """
             document.body.insertAdjacentHTML('beforebegin',"<header><meta 
             name='viewport' content='width=device-width, initial-scale=1.0, 
             maximum-scale=1.0, minimum-scale=1.0, user-scalable=no'> 
             </header>")
             """
    webView.evaluateJavaScript(js) { (html, error) in
    }
    
}

}

Upvotes: 0

Ilesh P

Reputation: 4036

Simple way to do this in Swift

extension WKWebView {

    /// load HTML String same font like the UIWebview
    ///
    //// - Parameters:
    ///   - content: HTML content which we need to load in the webview.
    ///   - baseURL: Content base url. It is optional.
    func loadHTMLStringWithMagic(content:String,baseURL:URL?){
        let headerString = "<header><meta name='viewport' content='width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, user-scalable=no'></header>"
        loadHTMLString(headerString + content, baseURL: baseURL)
    }
}

Just simply call this method and magic happen. ;)

webView.loadHTMLStringWithMagic(content: "<p> HTML content <p>", baseURL: nil)

OUTPUT:

Upvotes: 24

ishwar lal janwa

Reputation: 524

let description = "<p> HTML content <p>"
var headerString = "<header><meta name='viewport' content='width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0'></header>"
headerString.append(description)              
self.webView.loadHTMLString("\(headerString)", baseURL: nil)

Upvotes: 27

The font looks like smaller in WKWebView than in UIWebView

Answers (8)

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