fix(DefaultWebClient): allow file:// and javascript: navigations to fall through (#762)

Resolves #762

DefaultWebClient.shouldOverrideUrlLoading explicitly handles http/https,
then runs through phone/email/intent/wechat/alipay handlers, and finally
intercepts every remaining URL when mIsInterceptUnkownUrl is true (the
default). file:// links between bundled assets (the most common pattern
for offline H5 apps that hit this method) end up in that final branch,
which returns true and silently drops the navigation. The same is true
of javascript: URLs.

Two new scheme constants (FILE_SCHEME / JAVASCRIPT_SCHEME) are added
near SCHEME_SMS, and both overloads of shouldOverrideUrlLoading return
false as soon as they see one of those schemes, letting WebView handle
the navigation itself.

Author: jim-daf

agentweb-core/src/main/java/com/just/agentweb/DefaultWebClient.java

@@ -146,6 +146,14 @@ public class DefaultWebClient extends MiddlewareWebClientBase {
 	 * SMS scheme
 	 */
 	public static final String SCHEME_SMS = "sms:";
+	/**
+	 * file scheme - locally bundled assets and on-device files.
+	 */
+	public static final String FILE_SCHEME = "file://";
+	/**
+	 * javascript: scheme - bookmarklet-style URLs the WebView itself evaluates.
+	 */
+	public static final String JAVASCRIPT_SCHEME = "javascript:";
 	/**
 	 * 缓存当前出现错误的页面
 	 */
@@ -189,6 +197,13 @@ public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request
 		if (url.startsWith(HTTP_SCHEME) || url.startsWith(HTTPS_SCHEME)) {
 			return (webClientHelper && HAS_ALIPAY_LIB && isAlipay(view, url));
 		}
+		// Issue #762: navigations to file:// (e.g. links between bundled assets)
+		// and javascript: URLs must be handled by WebView itself. Letting them
+		// fall through into the unknown-URL branch below causes
+		// mIsInterceptUnkownUrl to silently drop the navigation.
+		if (url.startsWith(FILE_SCHEME) || url.startsWith(JAVASCRIPT_SCHEME)) {
+			return false;
+		}
 		if (!webClientHelper) {
 			return super.shouldOverrideUrlLoading(view, request);
 		}
@@ -278,6 +293,13 @@ public boolean shouldOverrideUrlLoading(WebView view, String url) {
 		if (url.startsWith(HTTP_SCHEME) || url.startsWith(HTTPS_SCHEME)) {
 			return (webClientHelper && HAS_ALIPAY_LIB && isAlipay(view, url));
 		}
+		// Issue #762: navigations to file:// (e.g. links between bundled assets)
+		// and javascript: URLs must be handled by WebView itself. Letting them
+		// fall through into the unknown-URL branch below causes
+		// mIsInterceptUnkownUrl to silently drop the navigation.
+		if (url.startsWith(FILE_SCHEME) || url.startsWith(JAVASCRIPT_SCHEME)) {
+			return false;
+		}
 		if (!webClientHelper) {
 			return false;
 		}