我知道之前可能已经问过这个问题，但我无法理解问题在哪里？
当互联网不可用时，应用程序强制停止。我用不同的方法来解决这个问题，但我不能，问题是什么？
对于检查网络，我使用了以下代码：
public static boolean isNetworkAvailable(Context context) {
ConnectivityManager conMan = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
if (conMan.getActiveNetworkInfo() != null && conMan.getActiveNetworkInfo().isConnected())
return true;
else
return false;
}
对于show alert，我在OnCreate方法中使用了它：
if(!isNetworkAvailable(this)) {
Toast.makeText(this,"No Internet connection",Toast.LENGTH_LONG).show();
}
所有MainActivity类都是这样的：
public class MainActivity extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener {
WebView webview;
String url = "http://hut.az/";
private ProgressDialog progressDialog;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
if(!isNetworkAvailable(this)) {
Toast.makeText(this,"No Internet connection",Toast.LENGTH_LONG).show();
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.addDrawerListener(toggle);
toggle.syncState();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
webview = (WebView) findViewById(R.id.webview1);
webview.getSettings().setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);
webview.getSettings().setJavaScriptEnabled(true);
webview.getSettings().setJavaScriptCanOpenWindowsAutomatically(true);
webview.setWebViewClient(new WebViewClient() {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
new MyAsynTask().execute(url);
return super.shouldOverrideUrlLoading(view, url);
}
});
new MyAsynTask().execute(this.url);
}
public static boolean isNetworkAvailable(Context context) {
ConnectivityManager conMan = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
if (conMan.getActiveNetworkInfo() != null && conMan.getActiveNetworkInfo().isConnected())
return true;
else
return false;
}
@Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
Intent myIntent = new Intent(getApplicationContext(), MainActivity.class);
startActivityForResult(myIntent, 0);
return true;
}
@SuppressWarnings("StatementWithEmptyBody")
@Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
FragmentManager fragmentManager = getFragmentManager();
if (id == R.id.nav_camera) {
url = "http://hut.az/arenda-kvartir/";
webview.setWebViewClient(new WebViewClient() {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
new MyAsynTask().execute(url);
return super.shouldOverrideUrlLoading(view, url);
}
});
new MyAsynTask().execute(this.url);
setTitle("Kiraye Evler");
} else if (id == R.id.nav_gallery) {
url = "http://hut.az/prodaja-kvartir/";
webview.setWebViewClient(new WebViewClient() {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
new MyAsynTask().execute(url);
return super.shouldOverrideUrlLoading(view, url);
}
});
new MyAsynTask().execute(this.url);
} else if (id == R.id.nav_slideshow) {
url = "http://hut.az/novostroyki/";
webview.setWebViewClient(new WebViewClient() {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
new MyAsynTask().execute(url);
return super.shouldOverrideUrlLoading(view, url);
}
});
new MyAsynTask().execute(this.url);
} else if (id == R.id.ticaret_obyekti) {
url = "http://hut.az/kommercheskaya/";
webview.setWebViewClient(new WebViewClient() {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
new MyAsynTask().execute(url);
return super.shouldOverrideUrlLoading(view, url);
}
});
new MyAsynTask().execute(this.url);
} else if (id == R.id.torpag_sahedi) {
url = "http://hut.az/doma-uchastki/";
webview.setWebViewClient(new WebViewClient() {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
new MyAsynTask().execute(url);
return super.shouldOverrideUrlLoading(view, url);
}
});
new MyAsynTask().execute(this.url);
} else if (id == R.id.kend_teserrufati) {
url = "http://hut.az/garaji/";
webview.setWebViewClient(new WebViewClient() {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
new MyAsynTask().execute(url);
return super.shouldOverrideUrlLoading(view, url);
}
});
new MyAsynTask().execute(this.url);
} else if (id == R.id.nav_manage) {
url = "http://hut.az/zarubejnaya-nedvijimost/";
webview.setWebViewClient(new WebViewClient() {
@Override
public boolean shouldOverrideUrlLoading(WebView view, String url) {
new MyAsynTask().execute(url);
return super.shouldOverrideUrlLoading(view, url);
}
});
new MyAsynTask().execute(this.url);
} else if (id == R.id.nav_share) {
Intent intent = new Intent();
intent.setAction(Intent.ACTION_SEND);
intent.setType("text/plain");
intent.putExtra(Intent.EXTRA_TEXT, url);
startActivity(Intent.createChooser(intent, "Share"));
} else if (id == R.id.nav_send) {
startActivity(new Intent(MainActivity.this, ElanYerlesdir.class));
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}
private class MyAsynTask extends AsyncTask<String, Void, Document> {
@Override
protected Document doInBackground(String... urls) {
Document document = null;
try {
document = Jsoup.connect(urls[0]).get();
document.getElementsByClass("header1").remove();
document.getElementsByClass("topbar clearfix").remove();
document.getElementsByClass("mapandslider").remove();
document.select("div#right_sidebar").remove();
document.select("div#left_sidebar").remove();
document.getElementsByClass("footer1").remove();
document.getElementsByClass("copyright").remove();
} catch (IOException e) {
e.printStackTrace();
}
return document;
}
protected void onPreExecute() {
super.onPreExecute();
progressDialog = new ProgressDialog(MainActivity.this);
progressDialog.setTitle("Yüklənir");
progressDialog.setMessage("Zəhmət olmasa gözləyin...");
progressDialog.setIndeterminate(false);
progressDialog.show();
}
@Override
protected void onPostExecute(Document document) {
super.onPostExecute(document);
webview.loadDataWithBaseURL(url, document.toString(), "text/html", "utf-8", "");
progressDialog.dismiss();
}
}
}
P.S Internet权限我也曾使用过：
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.INTERNET" />
答案 0 :(得分：0)
试试这个，
public static boolean isNetworkAvailable(Context activity) {
ConnectivityManager connectivity = (ConnectivityManager) activity
.getSystemService(Context.CONNECTIVITY_SERVICE);
if (connectivity == null) {
return false;
} else {
NetworkInfo[] info = connectivity.getAllNetworkInfo();
if (info != null) {
for (int i = 0; i < info.length; i++) {
if (info[i].getState() == NetworkInfo.State.CONNECTED) {
return true;
}
}
}
}
return false;
}