Implement local file assets

app/src/main/java/org/traccar/manager/MainFragment.java

@@ -16,26 +16,45 @@
 package org.traccar.manager;
 
 import android.content.pm.ApplicationInfo;
+import android.content.res.AssetManager;
+import android.net.Uri;
 import android.os.Build;
 import android.os.Bundle;
 import android.preference.PreferenceManager;
 import android.view.View;
+import android.webkit.MimeTypeMap;
+import android.webkit.WebResourceResponse;
 import android.webkit.WebSettings;
 import android.webkit.WebView;
+import android.webkit.WebViewClient;
 import android.webkit.WebViewFragment;
 
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.HttpURLConnection;
+import java.util.HashMap;
+import java.util.Map;
+
 public class MainFragment extends WebViewFragment {
 
+    private String version = "3.7";
+    private Uri serverUri;
+    private AssetManager assetManager;
+
     @Override
     public void onViewCreated(View view, Bundle savedInstanceState) {
         super.onViewCreated(view, savedInstanceState);
 
+        assetManager = getActivity().getAssets();
+
         if ((getActivity().getApplicationInfo().flags &= ApplicationInfo.FLAG_DEBUGGABLE) != 0) {
             if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
                 WebView.setWebContentsDebuggingEnabled(true);
             }
         }
 
+        getWebView().setWebViewClient(webViewClient);
+
         WebSettings webSettings = getWebView().getSettings();
         webSettings.setJavaScriptEnabled(true);
         webSettings.setDomStorageEnabled(true);
@@ -43,8 +62,79 @@ public class MainFragment extends WebViewFragment {
 
         String url = PreferenceManager.getDefaultSharedPreferences(
                 getActivity()).getString(MainActivity.PREFERENCE_URL, null);
+        serverUri = Uri.parse(url);
 
         getWebView().loadUrl(url);
     }
 
+    public String getMimeType(String url) {
+        String extension = MimeTypeMap.getFileExtensionFromUrl(url);
+        if (extension != null) {
+            switch (extension) {
+                case "js":
+                    return "text/javascript";
+                case "woff":
+                    return "application/font-woff";
+                case "woff2":
+                    return "application/font-woff2";
+                case "ttf":
+                    return "application/x-font-ttf";
+                case "eot":
+                    return "application/vnd.ms-fontobject";
+                case "svg":
+                    return "image/svg+xml";
+                default:
+                    return MimeTypeMap.getSingleton().getMimeTypeFromExtension(extension);
+            }
+        }
+        return null;
+    }
+
+    public WebResourceResponse loadFileFromAssets(String url, String file) throws IOException {
+        String mimeType = getMimeType(url);
+        String encoding = "UTF-8";
+        InputStream inputStream = assetManager.open(file);
+
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
+            int statusCode = HttpURLConnection.HTTP_OK;
+            String reasonPhase = "OK";
+            Map<String, String> responseHeaders = new HashMap<>();
+            responseHeaders.put("Access-Control-Allow-Origin", "*");
+            return new WebResourceResponse(mimeType, encoding, statusCode, reasonPhase, responseHeaders, inputStream);
+        } else {
+            return new WebResourceResponse(mimeType, encoding, inputStream);
+        }
+    }
+
+    private WebViewClient webViewClient = new WebViewClient() {
+
+        @SuppressWarnings("deprecation")
+        @Override
+        public WebResourceResponse shouldInterceptRequest(WebView view, String url) {
+            Uri uri = Uri.parse(url);
+            if (uri.getHost().equals(serverUri.getHost())) {
+                String path = uri.getPath();
+                if (!path.startsWith("/api")) {
+                    if (path.equals("/")) {
+                        path = "/release.html";
+                    }
+                    try {
+                        return loadFileFromAssets(url, "app/" + version + path);
+                    } catch (IOException e) {
+                        return null;
+                    }
+                }
+            } else if (uri.getHost().equals("cdnjs.cloudflare.com")) {
+                String path = uri.getPath().substring("/ajax/libs".length());
+                try {
+                    return loadFileFromAssets(url, "cdnjs" + path);
+                } catch (IOException e) {
+                    return null;
+                }
+            }
+            return null;
+        }
+
+    };
+
 }