android 判断 有没有网络 ，简单实现

版权声明：本文为博主原创文章，未经博主允许不得转载。 https://blog.csdn.net/bbtianshi/article/details/83540821

对应一个按钮 ，点

public class WlActivity extends AppCompatActivity {
Button btn;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_pdf);
        btn= findViewById(R.id.btn);
        btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // https://www.cnblogs.com/guanmanman/p/6769240.html

                if (isNetworkAvailable(WlActivity.this))
                {
                    Toast.makeText(getApplicationContext(), "当前有可用网络！", Toast.LENGTH_LONG).show();
                }
                else
                {
                    Toast.makeText(getApplicationContext(), "当前没有可用网络！", Toast.LENGTH_LONG).show();
                }

            }
        });


    }



    public boolean isNetworkAvailable(Activity activity)
    {
        Context context = activity.getApplicationContext();
        // 获取手机所有连接管理对象（包括对wi-fi,net等连接的管理）
        ConnectivityManager connectivityManager = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);

        if (connectivityManager == null)
        {
            return false;
        }
        else
        {
            // 获取NetworkInfo对象
            NetworkInfo[] networkInfo = connectivityManager.getAllNetworkInfo();

            if (networkInfo != null && networkInfo.length > 0)
            {
                for (int i = 0; i < networkInfo.length; i++)
                {
                    System.out.println(i + "===状态===" + networkInfo[i].getState());
                    System.out.println(i + "===类型===" + networkInfo[i].getTypeName());
                    // 判断当前网络状态是否为连接状态
                    if (networkInfo[i].getState() == NetworkInfo.State.CONNECTED)
                    {
                        return true;
                    }
                }
            }
        }
        return false;
    }

}

击对应吐司有没有忘了，这里没有封装 ，

下面这个对应的简单 在一个utils类里面 写上该方法，直接条用即可

    public static boolean isNetworkAvailable(Context context) {
        ConnectivityManager connectivity = (ConnectivityManager) context
                .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
                            || info[i].getState() == NetworkInfo.State.CONNECTING) {
                        return true;
                    }
                }
            }
        }
        return false;
    }

下面就是对应在activity里面调用 我的是一个button按钮的点击事件

NdK.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {

        if (!Util.isNetworkAvailable(GBActivity.this)) {
            Toast.makeText(GBActivity.this,"网络不可用",Toast.LENGTH_LONG).show();
            return;
        }
    }
});