我正在做一个通过应用程序使用Internet连接的应用程序。如果在使用应用程序时丢失了Internet连接,则应用程序将强行关闭。为避免这种情况,如果互联网不可用,我想显示一条警告信息。我怎样才能做到这一点。 在登录时,我正在使用以下代码检查连接。但是我怎样才能在后台进行整个应用。
private boolean haveInternet(){
NetworkInfo info = ((ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE)).getActiveNetworkInfo();
if (info==null || !info.isConnected()) {
return false;
}
if (info.isRoaming()) {
// here is the roaming option you can change it if you want to disable internet while roaming, just return false
return true;
}
return true;
}
谢谢..
答案 0 :(得分:40)
当连接状态发生变化时,您应该触发BroadcastReceiver
:
public class BroadCastSampleActivity extends Activity {
/** Called when the activity is first created. */
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
this.registerReceiver(this.mConnReceiver,
new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION));
}
private BroadcastReceiver mConnReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
boolean noConnectivity = intent.getBooleanExtra(ConnectivityManager.EXTRA_NO_CONNECTIVITY, false);
String reason = intent.getStringExtra(ConnectivityManager.EXTRA_REASON);
boolean isFailover = intent.getBooleanExtra(ConnectivityManager.EXTRA_IS_FAILOVER, false);
NetworkInfo currentNetworkInfo = (NetworkInfo) intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
NetworkInfo otherNetworkInfo = (NetworkInfo) intent.getParcelableExtra(ConnectivityManager.EXTRA_OTHER_NETWORK_INFO);
if(currentNetworkInfo.isConnected()){
Toast.makeText(getApplicationContext(), "Connected", Toast.LENGTH_LONG).show();
}else{
Toast.makeText(getApplicationContext(), "Not Connected", Toast.LENGTH_LONG).show();
}
}
};
}
然后在AndroidManifest
中,您可以检查是否有连接:
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
下载源代码 - here