由于webView存在安全漏洞,谷歌从5.1开始全面禁止系统应用使用webview,使用会导致应用崩溃错误提示:Caused by: java.lang.UnsupportedOperationException: For security reasons, WebView is not allowed in privileged processes 异常信息可以看出 是在 WebViewFactory.java 的getProvider 方法 抛出的。源码路径为 frameworks/base/core/java/android/webkit/WebViewFactory.java
static WebViewFactoryProvider getProvider() {
synchronized (sProviderLock) {
// For now the main purpose of this function (and the factory abstraction) is to keep
// us honest and minimize usage of WebView internals when binding the proxy.
if (sProviderInstance != null) return sProviderInstance; //如果sProviderInstance不为空直接返回
//1，判断，如果是系统id ，则抛出异常。
final int uid = android.os.Process.myUid();
if (uid == android.os.Process.ROOT_UID || uid == android.os.Process.SYSTEM_UID) {
throw new UnsupportedOperationException(
"For security reasons, WebView is not allowed in privileged processes");
}
StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads();
Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "WebViewFactory.getProvider()");
try {
//2
Class<WebViewFactoryProvider> providerClass = getProviderClass();
Trace.traceBegin(Trace.TRACE_TAG_WEBVIEW, "providerClass.newInstance()");
try {
//3 给 sProviderInstance 赋值
sProviderInstance = providerClass.getConstructor(WebViewDelegate.class)
.newInstance(new WebViewDelegate());
if (DEBUG) Log.v(LOGTAG, "Loaded provider: " + sProviderInstance);
return sProviderInstance;
} catch (Exception e) {
Log.e(LOGTAG, "error instantiating provider", e);
throw new AndroidRuntimeException(e);
} finally {
Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW);
}
} finally {
Trace.traceEnd(Trace.TRACE_TAG_WEBVIEW);
StrictMode.setThreadPolicy(oldPolicy);
}
}
}
如果是系统id,就抛出异常! 可以通过反射在调用webview 之前，给sProviderInstance 赋值，这样就可以了 在Application调用方法,兼容8.0
public static void hookWebView(){
int sdkInt = Build.VERSION.SDK_INT;
try {
Class<?> factoryClass = Class.forName("android.webkit.WebViewFactory");
Field field = factoryClass.getDeclaredField("sProviderInstance");
field.setAccessible(true);
Object sProviderInstance = field.get(null);
if (sProviderInstance != null) {
Log.i(TAG,"sProviderInstance isn‘t null");
return;
}
Method getProviderClassMethod;
if (sdkInt > 22) {
getProviderClassMethod = factoryClass.getDeclaredMethod("getProviderClass");
} else if (sdkInt == 22) {
getProviderClassMethod = factoryClass.getDeclaredMethod("getFactoryClass");
} else {
Log.i(TAG,"Don‘t need to Hook WebView");
return;
}
getProviderClassMethod.setAccessible(true);
Class<?> factoryProviderClass = (Class<?>) getProviderClassMethod.invoke(factoryClass);
Class<?> delegateClass = Class.forName("android.webkit.WebViewDelegate");
Constructor<?> delegateConstructor = delegateClass.getDeclaredConstructor();
delegateConstructor.setAccessible(true);
if(sdkInt < 26){//低于Android O版本
Constructor<?> providerConstructor = factoryProviderClass.getConstructor(delegateClass);
if (providerConstructor != null) {
providerConstructor.setAccessible(true);
sProviderInstance = providerConstructor.newInstance(delegateConstructor.newInstance());
}
} else {
Field chromiumMethodName = factoryClass.getDeclaredField("CHROMIUM_WEBVIEW_FACTORY_METHOD");
chromiumMethodName.setAccessible(true);
String chromiumMethodNameStr = (String)chromiumMethodName.get(null);
if (chromiumMethodNameStr == null) {
chromiumMethodNameStr = "create";
}
Method staticFactory = factoryProviderClass.getMethod(chromiumMethodNameStr, delegateClass);
if (staticFactory!=null){
sProviderInstance = staticFactory.invoke(null, delegateConstructor.newInstance());
}
}
if (sProviderInstance != null){
field.set("sProviderInstance", sProviderInstance);
Log.i(TAG,"Hook success!");
} else {
Log.i(TAG,"Hook failed!");
}
} catch (Throwable e) {
Log.w(TAG,e);
}
}