android控制wifi状态

wifi的五种状态

常量名	常量值	网卡状态
WIFI_STATE_DISABLED	1	WIFI网卡不可用
WIFI_STATE_DISABLING	0	WIFI正在关闭
WIFI_STATE_ENABLED	3	WIFI网卡可用
WIFI_STATE_ENABLING	2	WIFI网卡正在打开
WIFI_STATE_UNKNOWN	4	未知网卡状态

public class MainActivity extends Activity {
    WifiManager mWifiManager = null;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.open_wifi:
            mWifiManager = (WifiManager)MainActivity.this.getSystemService(Context.WIFI_SERVICE);
            mWifiManager.setWifiEnabled(true);
            if(mWifiManager.getWifiState() == 2)
            {
                Toast.makeText(MainActivity.this, "当前网卡状态为：WIFI正在打开...", Toast.LENGTH_SHORT).show();
            }
            else if(mWifiManager.getWifiState() == 3)
            {
                Toast.makeText(MainActivity.this, "当前网卡状态为：WIFI正常使用", Toast.LENGTH_SHORT).show();
            }
            break;
        case R.id.close_wifi:
            mWifiManager = (WifiManager)MainActivity.this.getSystemService(Context.WIFI_SERVICE);
            mWifiManager.setWifiEnabled(false);
            if(mWifiManager.getWifiState() == 0)
            {
                Toast.makeText(MainActivity.this, "当前网卡状态为：WIFI正在关闭...", Toast.LENGTH_SHORT).show();
            }
            else if(mWifiManager.getWifiState() == 1)
            {
                Toast.makeText(MainActivity.this, "当前网卡状态为：WIFI已关闭", Toast.LENGTH_SHORT).show();
            }
            break;
        case R.id.wifi_state:
            mWifiManager = (WifiManager)MainActivity.this.getSystemService(Context.WIFI_SERVICE);
            if(mWifiManager.getWifiState() == 0)
            {
                Toast.makeText(MainActivity.this, "当前网卡状态为：WIFI正在关闭...", Toast.LENGTH_SHORT).show();
            }
            else if(mWifiManager.getWifiState() == 1)
            {
                Toast.makeText(MainActivity.this, "当前网卡状态为：WIFI已关闭", Toast.LENGTH_SHORT).show();
            }
            else if(mWifiManager.getWifiState() == 2)
            {
                Toast.makeText(MainActivity.this, "当前网卡状态为：WIFI正在打开...", Toast.LENGTH_SHORT).show();
            }
            else if(mWifiManager.getWifiState() == 3)
            {
                Toast.makeText(MainActivity.this, "当前网卡状态为：WIFI正常使用", Toast.LENGTH_SHORT).show();
            }
            else if(mWifiManager.getWifiState() == 4)
            {
                Toast.makeText(MainActivity.this, "当前网卡状态为：WIFI状态未知", Toast.LENGTH_SHORT).show();
            }
            break;
        default:
            break;
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }

}

xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity" >

    <Button
        android:id="@+id/open_wifi"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="打开WIFI"
        android:onClick="onClick" />
    <Button
        android:id="@+id/close_wifi"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="关闭WIFI" 
        android:onClick="onClick"/>
    <Button
        android:id="@+id/wifi_state"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="WIFI状态" 
        android:onClick="onClick"/>
</LinearLayout>

添加权限:

<uses-permission android:name="android.permission.CHANGE_NETWORK_STATE" />
    <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
 
              CHANGE_NETWORK_STATE ：允许修改网络状态的权限。 
              CHANGE_WIFI_STATE ：允许修改 WIFI 状态的权限。 
              ACCESS_NETWORK_STATE ：允许访问网络状态的权限。 
              ACCESS_WIFI_STATE ：允许访问 WIFI 状态的权限。