Android 加载本地 Web 项目

1. web 项目放在assert 文件夹下

wv.loadUrl("file:///android_asset/xxx/xxx/index.html");

Jav a script 引用 assert 中的资源，路径需要预先约定好

&lt;link rel="xxx" href="/android_asset/xxx/xxx.js"&gt;

2. web 项目放在外置 存储

And roid端加载 html 方式

wv.loadUrl("file:///sdcard/Android/data/xxx/files/Download/xxx/index.html");

Jav a script 引用外置存储中的资源，出于安全的考虑，禁止直接路径的调用，而需要 We bView 做资源拦截，替换为本地资源地址，然后以文件流的方式，回传给前端

		WebView wv = find....
        WebSettings settings = wv.getSettings();
        settings.setJavaScriptEnabled(true);
        settings.setAllowFileAccess(true);
        settings.setAllowFileAccessFromFileURLs(true);
        settings.setAllowContentAccess(true);
        settings.setDomStorageEnabled(true);

        wv.setWebViewClient(new MyWebViewClient());
        
 public class MyWebViewClient extends WebViewClient {
        @Nullable
        @Override
        public WebResourceResponse shouldInterceptRequest(WebView view, WebResourceRequest request) {
            String url = request.getUrl().toString();
            InputStream inputStream = null;
            String mimeType = "";
           
            if( url.startsWith("file:///assets")) {
                if(url.endsWith("js")) {
                    mimeType = "text/javascript";
                } else if(url.endsWith("css")) {
                    mimeType = "text/css";
                } else if(url.endsWith("json")) {
                    mimeType = "application/json";
                } else if(url.endsWith("bin")) {
                    mimeType = "application/octet-stream";
                }

                File externalFilesDir = getExternalFilesDir(Environment.DIRECTORY_DOWNLOADS);
                String loadPath = url.replace("file:///", externalFilesDir.getAbsolutePath() + File.separator +"dist"+ File.separator);
                File loadFile = new File(loadPath);
                try {
                    inputStream = new FileInputStream(loadFile);
                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }

            if(inputStream != null) {
                Map<String, String> responseHeaders = new HashMap<>();
                responseHeaders.put("Connection", "close");
                responseHeaders.put("Content-Type", mimeType);
                responseHeaders.put("Date", "$dateString GMT");
                responseHeaders.put("Access-Control-Allow-Origin", "*");
                responseHeaders.put("Access-Control-Allow-Methods", "GET, POST, DELETE, PUT, OPTIONS");
                responseHeaders.put("Access-Control-Max-Age", "600");
                responseHeaders.put("Access-Control-Allow-Headers", "accept, authorization, Content-Type");
                String encoding = "utf-8";
                int statusCode = 200;
                String reasonPhrase = "SUCCESS";
                return new WebResourceResponse(mimeType, encoding, statusCode, reasonPhrase, responseHeaders, inputStream);
            }

            return super.shouldInterceptRequest(view, request);
        }
    }