android检测网络连接状态示例讲解

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.INTERNET"/>

/** 
 * 对网络连接状态进行判断 
 * @return  true, 可用； false， 不可用 
 */  
private boolean isOpenNetwork() {  
    ConnectivityManager connManager = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);  
    if(connManager.getActiveNetworkInfo() != null) {  
        return connManager.getActiveNetworkInfo().isAvailable();  
    }  

    return false;  
}  

/** 
 * 访问百度主页，网络不可用则需设置 
 */  
private void initMoreGames() {  
    String URL_MOREGAMES = "http://www.baidu.com";  
    mWebView = (WebView) findViewById(R.id.view_gamesort);  

    if (mWebView != null) {  
        mWebView.requestFocus();  
        WebSettings webSettings = mWebView.getSettings();  
        if (webSettings != null) {  
            webSettings.setJavaScriptEnabled(true);  
            webSettings.setCacheMode(MODE_PRIVATE);  
            webSettings.setDefaultTextEncodingName("utf-8");  
        }  

        // 判断网络是否可用  
        if(isOpenNetwork() == true) {  
            mWebView.loadUrl(URL_MOREGAMES);  
        } else {  
            AlertDialog.Builder builder = new AlertDialog.Builder(MoreGamesActivity.this);  
            builder.setTitle("没有可用的网络").setMessage("是否对网络进行设置?");  

            builder.setPositiveButton("是", new DialogInterface.OnClickListener() {  
                @Override  
                public void onClick(DialogInterface dialog, int which) {  
                    Intent intent = null;  

                    try {  
                        String sdkVersion = android.os.Build.VERSION.SDK;  
                        if(Integer.valueOf(sdkVersion) > 10) {  
                            intent = new Intent(android.provider.Settings.ACTION_WIRELESS_SETTINGS);  
                        }else {  
                            intent = new Intent();  
                            ComponentName comp = new ComponentName("com.android.settings", "com.android.settings.WirelessSettings");  
                            intent.setComponent(comp);  
                            intent.setAction("android.intent.action.VIEW");  
                        }  
                        MoreGamesActivity.this.startActivity(intent);  
                    } catch (Exception e) {  
                        Log.w(TAG, "open network settings failed, please check...");  
                        e.printStackTrace();  
                    }  
                }  
            }).setNegativeButton("否", new DialogInterface.OnClickListener() {  
                @Override  
                public void onClick(DialogInterface dialog, int which) {  
                    dialog.cancel();          
                    finish();  
                }  
            }).show();  
        }  
    } else {  
        Log.w(TAG, "mWebView is null, please check...");  
    }  
}