当应用程序无法连接时显示“没有互联网连接”屏幕

Question

我需要的是当用户打开我的应用程序并且他或她没有任何互联网连接时，webview会显示我在Photoshop中设计的屏幕。所以基本上不是标准的没有网络错误

这里是我的xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:ads="http://schemas.android.com/apk/res-auto" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:background="#ffffff" 
    android:clickable="false" 
    tools:context=".MyActivity"> 

    <TextView 
     android:id="@+id/textView" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignParentEnd="true" 
     android:layout_alignParentLeft="true" 
     android:layout_alignParentRight="true" 
     android:layout_alignParentStart="true" 
     android:layout_alignParentTop="true" 
     android:background="#ffffff" 
     android:gravity="center" 
     android:text="@string/vu" 
     android:textColor="#000000" 
     android:textSize="60sp" /> 

    <WebView 
     android:id="@+id/webView" 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_alignParentBottom="true" 
     android:layout_alignParentEnd="true" 
     android:layout_alignParentLeft="true" 
     android:layout_alignParentRight="true" 
     android:layout_alignParentStart="true" 
     android:layout_below="@+id/textView" /> 

    <com.google.android.gms.ads.AdView 
     android:id="@+id/adView" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:layout_alignParentBottom="true" 
     android:layout_alignParentLeft="true" 
     android:layout_alignParentStart="true" 
     ads:adSize="BANNER" 
     ads:adUnitId="ca-app-pub-3486775169258180/1572732950" /> 

</RelativeLayout> 

，这里是java类 -

public class MyActivity extends Activity { 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_my); 

     TextView tv = (TextView) findViewById(R.id.textView); 
     Typeface typeface = Typeface.createFromAsset(getAssets(), "BebasNeue Light.ttf"); 
     tv.setTypeface(typeface); 
     WebView webView = (WebView) findViewById(R.id.webView); 
     webView.loadUrl(""); 
     webView.setWebViewClient(new WebViewClient()); 
     webView.setVerticalScrollBarEnabled(false); 
     webView.setOverScrollMode(View.OVER_SCROLL_NEVER); 
     // Look up the AdView as a resource and load a request. 
     AdView adView = (AdView) this.findViewById(R.id.adView); 
     AdRequest adRequest = new AdRequest.Builder().build(); 
     adView.loadAd(adRequest); 
    } 
} 

Answer 1

你可以尝试这样的：

private boolean haveNetworkConnection() { 
    boolean haveConnectedWifi = false; 
    boolean haveConnectedMobile = false; 

    ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); 
    NetworkInfo[] netInfo = cm.getAllNetworkInfo(); 
    for (NetworkInfo ni : netInfo) { 
     if (ni.getTypeName().equalsIgnoreCase("WIFI")) 
      if (ni.isConnected()) 
       haveConnectedWifi = true; 
     if (ni.getTypeName().equalsIgnoreCase("MOBILE")) 
      if (ni.isConnected()) 
       haveConnectedMobile = true; 
    } 
    return haveConnectedWifi || haveConnectedMobile; 
}