简单的webView与js交互

一、创建assets文件夹，在文件夹中创建一个html文件

		

	
	

	//js代码
	

二、在activity中写入

	  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    webView =(WebView)findViewById(R.id.webView);
    button_js =(Button)findViewById(R.id.button_js);
    WebSettings settings = webView.getSettings();

    settings.setJavaScriptEnabled(true);
    settings.setJavaScriptCanOpenWindowsAutomatically(true);

    webView.loadUrl("file:////android_asset/nie.html");

    button_js.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            webView.post(new Runnable() {
                @Override
                public void run() {
                    webView.loadUrl("javascript:CallBack()");
                }
            });
        }
    });

    webView.setWebChromeClient(new WebChromeClient(){
        @Override
        public boolean onJsAlert(WebView view, String url, String message, final JsResult result) {
            AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
            builder.setTitle("Alert");
            builder.setMessage(message);
            builder.setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    result.confirm();
                }
            });
            builder.setCancelable(false);
            builder.create().show();
            return true;
        }
    });

}
注意：记得写入权限