在WebView中检查Internet连接 [英] Checking Internet connection in WebView
问题描述
您好,程序员在那里!
我的WebView-App出现问题...
I'm haveing a problem with my WebView-App...
我想在启动时添加一个连接检查",当没有可用的Internet连接或WebView超时时会弹出一个错误.我无法自己完成它,因为我是Android编程的新手.
I want to add a "Connection-check" on startup that's popping up an error when no Internet-connection is aviable or the WebView is timed out. I can't get it done by myself because I'm new in Android-programming.
我还想添加一个选项菜单,在这里我可以重新加载实际页面.
I also want to add an options-menu where i can reload the actual page.
希望有人可以帮助我...
Hope someone can help me...
实际代码:
package net.schwarzis.htl_cloud;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.ProgressDialog;
import android.os.Bundle;
import android.util.Log;
import android.view.KeyEvent;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
@SuppressLint("JavascriptInterface") public class MainActivity extends Activity {
/** Called when the activity is first created. */
private WebView browser = null;
public boolean shouldOverrideUrlLoading(WebView view, String url) {
browser.loadUrl(url);
return true;
}
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// connect to our browser so we can manipulate it
browser = (WebView) findViewById(R.id.mybrowser);
// get settings so we can config our WebView instance
WebSettings settings = browser.getSettings();
// JavaScript? Of course!
settings.setJavaScriptEnabled(true);
// clear cache
browser.clearCache(true);
final ProgressDialog pd=new ProgressDialog(this);
pd.setMessage("Lade...");
browser.setWebViewClient(new WebViewClient() {
public void onPageFinished(WebView view, String url) {
pd.dismiss();
}
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
pd.show();
browser.loadUrl(url);
return true;
}
});
// this is necessary for "alert()" to work
browser.setWebChromeClient(new WebChromeClient());
// add our custom functionality to the javascript environment
browser.addJavascriptInterface(new MyCoolJSHandler(), "Cloud");
// load a page to get things started
pd.show();
browser.loadUrl("http://cloud.schwarzis.net");
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
final ProgressDialog pd=new ProgressDialog(this);
pd.setMessage("Lade...");
if(event.getAction() == KeyEvent.ACTION_DOWN){
switch(keyCode)
{
case KeyEvent.KEYCODE_BACK:
if(browser.canGoBack() == true){
pd.show();
browser.goBack();
}else{
pd.show();
finish();
}
pd.dismiss();
return true;
}
}
return super.onKeyDown(keyCode, event);
}
final class MyCoolJSHandler
{
// write to LogCat (Info)
public void Info(String str) {
Log.i("GoingNative",str);
}
// write to LogCat (Error)
public void Error(String str) {
Log.e("GoingNative",str);
}
// Kill the app
public void EndApp() {
finish();
}
}
}
推荐答案
以下用户检查互联网连接的方法是否可用.
User below method to check internet connection is available or not.
public boolean isNetworkAvailable() {
// Get Connectivity Manager class object from Systems Service
ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
// Get Network Info from connectivity Manager
NetworkInfo networkInfo = cm.getActiveNetworkInfo();
// if no network is available networkInfo will be null
// otherwise check if we are connected
if (networkInfo != null && networkInfo.isConnected()) {
return true;
}
return false;
}
您需要在AndroidMenifest.xml文件中提供以下权限
You need to provide below permissions in AndroidMenifest.xml file
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
这篇关于在WebView中检查Internet连接的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!