Android中的WebView加载陈旧的内容
问题描述：
我正在制作一个应用程序，它使用webview显示来自登录用户的url的内容。它是一个非常基本和小型的应用程序。我的问题是用户注销并且其他用户登录，显示以前加载的内容（过时的内容）。这里的java类：Android中的WebView加载陈旧的内容
import android.annotation.TargetApi;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.graphics.Bitmap;
import android.os.Build;
import android.os.Bundle;
import android.support.v7.app.AlertDialog;
import android.util.Log;
import android.view.View;
import android.webkit.WebResourceError;
import android.webkit.WebResourceRequest;
import android.webkit.WebResourceResponse;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;
import java.util.HashMap;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
public class WebViewActivity extends Activity {
boolean clearHistory;
private final String API_KEY = "apiKey";
private final String TOKEN = "token";
private WebView mWebView;
String TAG="Response";
TextView topbar;
LinearLayout parentLayout;
HashMap<String, String> maps = new HashMap<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_webview);
mWebView =(WebView)findViewById(R.id.webview1);
mWebView.stopLoading();
topbar=(TextView)findViewById(R.id.topbar);
parentLayout=(LinearLayout)findViewById(R.id.parentLayout);
SharedPreferences pref = getSharedPreferences("MyPref", 0);
final String webviewUrl = pref.getString("webviewUrl", "");
final String token = pref.getString("app_token", "");
mWebView.getSettings().setJavaScriptEnabled(true);
mWebView.setScrollBarStyle(WebView.SCROLLBARS_OUTSIDE_OVERLAY);
topbar.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
AlertDialog.Builder alertDialog = new AlertDialog.Builder(WebViewActivity.this);
alertDialog.setTitle("Confirm Logout");
alertDialog.setMessage("Are you sure you want to logout?");
alertDialog.setIcon(R.drawable.smlalo);
alertDialog.setPositiveButton("Logout", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int which) {
SharedPreferences pref = getSharedPreferences(
"MyPref", 0);
SharedPreferences.Editor editor = pref.edit();
editor.putString("webviewUrl", "");
editor.putString("app_token", "");
editor.commit();
maps.put(TOKEN,token);
maps.put(API_KEY, BuildConfig.API_KEY_VALUE);
RestClient.getApiInterface().logout(maps).enqueue(new Callback<String>() {
@Override
public void onResponse(Call<String> call, Response<String> response) {
startActivity(new Intent(WebViewActivity.this, MainActivity.class));
finish();
}
@Override
public void onFailure(Call<String> call, Throwable t) {
}
});
}
});
// Setting Negative "NO" Button
alertDialog.setNegativeButton("NO", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
}
});
final ProgressDialog progressDialog = ProgressDialog.show(WebViewActivity.this, "", "Loading...");
mWebView.setWebViewClient(new WebViewClient() {
@Override
public void onLoadResource(WebView view, String url) {
view.clearHistory();
super.onLoadResource(view,url);
}
@Override
public void onPageStarted(WebView view, String url, Bitmap favicon)
{
progressDialog.show();
super.onPageStarted(view, url, favicon);
}
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
Log.i(TAG, "Processing webview url click...");
// view.loadUrl(url);
super.shouldOverrideUrlLoading(view, url);
return false;
}
@TargetApi(Build.VERSION_CODES.M)
@Override
public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
// view.loadUrl(request.getUrl().toString());
super.shouldOverrideUrlLoading(view, request);
return false;
}
public void onPageCommitVisible(WebView view, String url) {
view.clearHistory();
view.clearCache(true);
}
@Override
public void onPageFinished(WebView view, String url) {
Log.i(TAG, "Finished loading URL: " +url);
topbar.setVisibility(View.VISIBLE);
if (progressDialog.isShowing()) {
progressDialog.dismiss();
}
/*if (clearHistory)
{
clearHistory = false;
mWebView.clearHistory();
mWebView.clearCache(true);
if (progressDialog.isShowing()) {
progressDialog.dismiss();
}
}*/
super.onPageFinished(view, url);
}
@Override
public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
Log.e(TAG, "Error: " + description);
new android.app.AlertDialog.Builder(WebViewActivity.this)
.setTitle("Error")
.setMessage(description)
.setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// continue with delete
}
})
.setIcon(android.R.drawable.ic_dialog_alert)
.show();
if (progressDialog.isShowing()) {
progressDialog.dismiss();
}
super.onReceivedError(view,errorCode,description,failingUrl);
}
@TargetApi(Build.VERSION_CODES.M)
@Override
public void onReceivedError(WebView view, WebResourceRequest request, WebResourceError error) {
new android.app.AlertDialog.Builder(WebViewActivity.this)
.setTitle("Error")
.setMessage(error.getDescription())
.setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// continue with delete
}
})
.setIcon(android.R.drawable.ic_dialog_alert)
.show();
super.onReceivedError(view, request, error);
}
@TargetApi(Build.VERSION_CODES.LOLLIPOP)
@Override
public void onReceivedHttpError(WebView view,
WebResourceRequest request, WebResourceResponse errorResponse) {
Toast.makeText(WebViewActivity.this, "WebView Error" + errorResponse.getReasonPhrase(), Toast.LENGTH_SHORT).show();
super.onReceivedHttpError(view, request, errorResponse);
}
});
/*mWebView.loadUrl("about:blank");
mWebView.reload();*/
mWebView.loadUrl(webviewUrl);
// clearHistory = true;
// mWebView.reload();
}
}
和这里的布局文件：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:id="@+id/parentLayout"
android:layout_height="fill_parent"
tools:context=".SplashActivity">
<RelativeLayout
android:background="@color/colorPrimary"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_weight=".2"
android:padding="10dp"
android:id="@+id/topbarbbb">
<ImageView
android:text="@string/coachapp"
android:layout_width="wrap_content"
android:layout_centerVertical="true"
android:src="@drawable/smlalo"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_centerInParent="true"
android:id="@+id/imageView2" />
<TextView
android:text="Logout"
android:textSize="12sp"
android:layout_height="wrap_content"
android:textColor="#ffffff"
android:visibility="gone"
style="@style/Base.TextAppearance.AppCompat.Button"
android:id="@+id/topbar"
android:layout_width="wrap_content"
android:layout_alignParentRight="true"
android:layout_centerInParent="true">
</TextView>
</RelativeLayout>
<WebView android:id="@+id/webview1"
android:layout_below="@+id/topbarbbb"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1" />
</LinearLayout>
另外提一下，我已经调试和研究这一点。 sharedpreferences不是问题，正在检索的网址是我想要显示的网址。它在浏览器中正确打开。已尝试所有以前的答案，如Clear previously loaded Webview's content before loading the next one,clear webview history和这一个：Destroying the WebView。这些都不适合我。
我真的很感谢一些帮助。
答
此问题可能是由于保存在您的Web视图的JavaScript饼干。在打开你的webview之前刷新cookies。
答
我想通了。因为在webview中使用javascript，结果导致创建cookie。我只需添加代码即可在成功注销后清除Cookie。下面是我用什么：
@SuppressWarnings("deprecation")
public static void clearCookies(Context context)
{
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP_MR1) {
Log.d(C.TAG, "Using clearCookies code for API >=" + String.valueOf(Build.VERSION_CODES.LOLLIPOP_MR1));
CookieManager.getInstance().removeAllCookies(null);
CookieManager.getInstance().flush();
} else
{
Log.d(C.TAG, "Using clearCookies code for API <" + String.valueOf(Build.VERSION_CODES.LOLLIPOP_MR1));
CookieSyncManager cookieSyncMngr=CookieSyncManager.createInstance(context);
cookieSyncMngr.startSync();
CookieManager cookieManager=CookieManager.getInstance();
cookieManager.removeAllCookie();
cookieManager.removeSessionCookie();
cookieSyncMngr.stopSync();
cookieSyncMngr.sync();
}
}
完整的答案可以在这里找到：clear cookies webview
请不要[删除和转贴问题]（http://*.com/questions/41907714/webview-in-android-loading-stale-content）。只需使用任何新信息编辑原始帖子，就会将其置于活动队列的顶部。 –
我明白，但我收录了一些我不应该拥有的东西。编辑也是行不通的，因为有人有机会看到它。所以我必须纠正并重新发布。 – ashishbahl