当id =“ mode”时，我试图获取h1的值，但它仅返回I/chromium: [INFO:CONSOLE(1)] "Uncaught TypeError: Cannot read property 'innerHTML' of null", source: about:blank (1)。当我尝试直接在webView中加载html String时，它工作正常。也许您知道正确的方法。
fun getMode(ip: String): String {
var mode = ""
wvDevice[0].settings.javaScriptEnabled = true
wvDevice[0].settings.domStorageEnabled = true
wvDevice[0].settings.databaseEnabled = true
wvDevice[0].webViewClient = object : WebViewClient() {
override fun onPageFinished(view: WebView, url: String) {
view.evaluateJavascript("document.getElementById('mode').innerHTML")
{ value ->
value.forEach {
val splitted = value.split("\"")
for (i in splitted.indices){
if (splitted[i] == "RGB" || splitted[i] == "TW"){
mode = splitted[i]
println("mode: $mode")
}
}
}
}
}
}
/*wvDevice[0].loadData("<html><head><meta name=\"viewport\" content=\"width=device-width, initial-scale=1\">\n" +
"<link rel=\"icon\" href=\"data:,\">\n" +
"<link rel=\"stylesheet\" href=\"https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css\">\n" +
"<script src=\"https://cdnjs.cloudflare.com/ajax/libs/jscolor/2.0.4/jscolor.min.js\"></script>\n" +
"</head><body><div class=\"container\"><div class=\"row\"><h1 id=\"mode\">TW</h1><h2>533</h2></div>\n" +
"<a class=\"btn btn-primary btn-lg\" href=\"%23\" id=\"change_color\" role=\"button\">Change Color</a> \n" +
"<input class=\"jscolor {onFineChange:'update(this)'}\" id=\"rgb\" autocomplete=\"off\" style=\"background-image: none; background-color: rgb(255, 255, 255); color: rgb(0, 0, 0);\"></div>\n" +
"<script>function update(picker) {document.getElementById('rgb').innerHTML = Math.round(picker.rgb[0]) + ', ' + Math.round(picker.rgb[1]) + ', ' + Math.round(picker.rgb[2]);\n" +
"document.getElementById(\"change_color\").href=\"?r\" + Math.round(picker.rgb[0]) + \"g\" + Math.round(picker.rgb[1]) + \"b\" + Math.round(picker.rgb[2]) + \"&\";}</script>\n" +
"\n" +
"</body></html>", "text/html; charset=utf-8", "UTF-8")*/
wvDevice[0].loadUrl(ip)
return mode
尝试直接评估它，而不将其包装到函数中。使用当前代码，您不执行该功能。
wvDevice.evalueateJavascript("document.getElementById('mode')", object : ValueCallback<String>() {
override fun onReceiveValue(value: String) {
println(value)
}
});