判断当前的网络状态并跳转到系统设置

    //调用方法，返回当前的网络连接情况
    boolean networkConnected = isNetworkConnected(MainActivity.this);
    if(networkConnected)
    {
        Toast.makeText(MainActivity.this,"有网络连接",Toast.LENGTH_SHORT).show();
        //initview();
    }else
    {
        Toast.makeText(MainActivity.this,"断网了.....",Toast.LENGTH_SHORT).show();
        //弹出框提示连接网络
        AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
        builder.setTitle("网络连接")
                .setMessage("亲,网络断开咯...")
                .setIcon(R.mipmap.ic_launcher_round)
                .setPositiveButton("去设置", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialogInterface, int i) {
                        Intent intent = null;
                        // 先判断当前系统版本
                        if(android.os.Build.VERSION.SDK_INT > 10){
                            // 3.0以上跳转到系统设置
                            intent = new Intent(android.provider.Settings.ACTION_WIRELESS_SETTINGS);
                        }else{
                            //跳转到系统设置
                            intent = new Intent();
                            intent.setClassName("com.android.settings", "com.android.settings.WirelessSettings");
                        }
                        startActivity(intent);
                    }
                });
        builder.setNegativeButton("残忍退出", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialogInterface, int i) {
                //app.getInstance().add(MainActivity.this);
            }
        });
        builder.create().show();
    }
    initview();
}
//判断当前是否有网络连接
// {我也不知道啥意思，，复制吧，，兄弟，看懂了私聊我一下，教教我，谢谢}
public boolean isNetworkConnected(Context context)
{
    if (context != null) {
        ConnectivityManager mConnectivityManager = (ConnectivityManager) context
                .getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo mNetworkInfo = mConnectivityManager.getActiveNetworkInfo();
        if (mNetworkInfo != null) {
            return mNetworkInfo.isAvailable();
        }
    }
    return false;
}