我想在 WebView 中将自定义 CSS 应用到外部网页中，就像下面一样
webView.loadUrl("<style>body {font-size:15px;}</style>");
webView.loadUrl("http://www.stackoverflow.com");
最佳答案
您可以使用 javascript: URL 功能注入(inject)自定义 JS。
下面是如何使用它从 Java 添加 CSS 规则:
/**
* Creates a CSS element in the <head> section of the Web page and assigns it
* to a `customSheet` JS variable
*/
private final static String CREATE_CUSTOM_SHEET =
"if (typeof(document.head) != 'undefined' && typeof(customSheet) == 'undefined') {"
+ "var customSheet = (function() {"
+ "var style = document.createElement(\"style\");"
+ "style.appendChild(document.createTextNode(\"\"));"
+ "document.head.appendChild(style);"
+ "return style.sheet;"
+ "})();"
+ "}";
/**
* Adds CSS properties to the loaded Web page. A <head> section should exist when this method is called.
* The Web view should be configured with `.getSettings().setJavaScriptEnabled(true);`
*
* @param webView Web view to inject into
* @param cssRules CSS rules to inject
*/
void injectCssIntoWebView(WebView webView, String... cssRules) {
StringBuilder jsUrl = new StringBuilder("javascript:");
jsUrl
.append(CREATE_CUSTOM_SHEET)
.append("if (typeof(customSheet) != 'undefined') {");
int cnt = 0;
for (String cssRule : cssRules) {
jsUrl
.append("customSheet.insertRule('")
.append(cssRule)
.append("', ")
.append(cnt++)
.append(");");
}
jsUrl.append("}");
webView.loadUrl(jsUrl.toString());
}
下面是上述方法的使用示例:
@Override
public void onPageFinished(WebView webView, String url) {
// Several people probably worked hard on the design of this Web page, let's hope they won't see what's next
injectCssIntoWebView(
webView,
"div { border: 4px solid yellow; }",
"p { border: 4px solid green; }",
"a { border: 4px solid black; }",
"img { border: 4px solid blue; }"
);
}
关于Android - 如何将自定义 css 注入(inject) webview 中的外部网页，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/8741735/