华为系统更新后安装了一个谷歌6月安全补丁的东西，然后之前写的调h5页面的部分就出现了问题，后台查过发现是Android端调h5页面时cookie没能带过去，导致了登录失败。于是对setCookie部分的代码进行了调试，发现单步运行时只要在setCookie部分时多等一会页面就可以正常打开，所以怀疑是异步的问题，先是在网上查了一通，说是这种情况可以让程序多睡会，但是这种解决方法并没有成功，而且觉得这么写代码有点别扭，于是就又查了一下设置Cookie部分的官方说明，发现 cookieManager.removeAllCookies其实是异步函数，之前写代码的人把他当同步用了，导致setCookie完成后，removeAllCookies函数才执行完的，把填进去的cookie又给移除了，所以导致了打开页面的失败。没安补丁之前，可能是cookie都带过去了，remove函数才执行完，安补丁后remov函数的运行速度提升了，但是具体原因不明，因为查不到补丁的内容，总之无论如何，异步函数当同步使用是万万不能的。
以下是改之前错误的代码，removeAllCookies被当成了同步函数使用
void fun(){
...
addCookies();
mWebview = (SystemWebView) appView.getView();
engine = (SystemWebViewEngine) appView.getEngine();
mWebview.setWebViewClient(new SystemWebViewClient(engine){
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
super.onPageStarted(view, url, favicon);
}
...
});
}
private void addCookies() {
CookieManager cookieManager = CookieManager.getInstance();
cookieManager.removeAllCookie();
cookieManager.setAcceptCookie(true);
List<Cookie> cookieList = MainApp.getInstance().getGlobalState().getCookies();
for (Cookie cookie: cookieList){
String cookieString = cookie.name() + "=" + cookie.value();
cookieManager.setCookie(url, cookieString);
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
cookieManager.flush();
} else {
CookieSyncManager.createInstance(this);
CookieSyncManager.getInstance().sync();
}
}
以下是改后的代码，removeAllCookies()有一个完成后会在当前线程调用的方法，利用他remove完成后在set就没问题了，而且addCookie()的调用被移进了onPageStarted之前，不然，之前那么写的话会先完成调用onPageStarted()，后完成addCookie()的调用，cookie依然不能设置成功。addCookie()不能放在onPageStarted中，应该加载完cookie再加载url，在loadUrl之前调用。
void fun(){
mWebview = (SystemWebView) appView.getView();
engine = (SystemWebViewEngine) appView.getEngine();
mWebview.setWebViewClient(new SystemWebViewClient(engine){
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon) {
// addCookies();
super.onPageStarted(view, url, favicon);
}
...
});
}
private void addCookies() {
CookieManager cookieManager = CookieManager.getInstance();
cookieManager.setAcceptCookie(true);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
cookieManager.removeAllCookies(new ValueCallback<Boolean>() {
@Override
public void onReceiveValue(Boolean value) {
setCookie(cookieManager);
}
});
}else{
cookieManager.removeAllCookie();
setCookie(cookieManager);
}
}
void setCookie( CookieManager cookieManager){
List<Cookie> cookieList = MainApp.getInstance().getGlobalState().getCookies();
for (Cookie cookie: cookieList){
String cookieString = cookie.name() + "=" + cookie.value();
cookieManager.setCookie(url, cookieString);
}
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
cookieManager.flush();
} else {
CookieSyncManager.createInstance(this);
CookieSyncManager.getInstance().sync();
}
loadUrl();
}
这是removeAllCookies()方法的完整说明
/**
* Removes all cookies.
* <p>
* This method is asynchronous.
* If a {@link ValueCallback} is provided,
* {@link ValueCallback#onReceiveValue(T) onReceiveValue()} will be called on the current
* thread's {@link android.os.Looper} once the operation is complete.
* The value provided to the callback indicates whether any cookies were removed.
* You can pass {@code null} as the callback if you don't need to know when the operation
* completes or whether any cookies were removed, and in this case it is safe to call the
* method from a thread without a Looper.
* @param callback a callback which is executed when the cookies have been removed
*/
public abstract void removeAllCookies(ValueCallback<Boolean> callback);