Android学习笔记之WI-FI(1)
<1>什么是Wi-Fi?Wi-Fi是一种可以将个人电脑、手持设备(如PDA、手机)等终端以无线方式互相连接的技术。Wi-Fi是一个无线网路通信技术的品牌,由Wi-Fi联盟(Wi-FiAlliance)所持有。
Wi-Fi 原先是无线保真的缩写,Wi-Fi 的英文全称为wireless fidelity,在无线局域网的范畴是指“无线相容性认证”,实质上是一种商业认证,同时也是一种无线联网的技术,以前通过网线连接电脑,而现在则是通过无线电波来连网;常见的就是一个无线路由器,那么在这个无线路由器的电波覆盖的有效范围都可以采用WIFI连接方式进行联网,如果无线路由器连接了一条ADSL线路或者别的上网线路,则又被称为“热点”。
<2>获取WI-FI网卡的状态(常量)
public static final int WIFI_STATE_DISABLED
Wi-Fi is disabled. WI-FI网卡不可用
Constant Value(常量值): 1 (0x00000001)
public static final int WIFI_STATE_DISABLING
Wi-Fi is currently being disabled. WI-FI网卡正在关闭
The state will change to WIFI_STATE_DISABLED if it finishes successfully.
最终状态会变成WI-FI网卡不可用
Constant Value(常量值): 0 (0x00000000)
public static final int WIFI_STATE_ENABLED
Wi-Fi is enabled. WI-FI网卡可用
Constant Value(常量值): 3 (0x00000003)
public static final int WIFI_STATE_ENABLING
Wi-Fi is currently being enabled. WI-FI网卡正在打开
The state will change to WIFI_STATE_ENABLED if it finishes successfully.
最终状态会变成WI-FI网卡可用
Constant Value(常量值): 2 (0x00000002)
public static final int WIFI_STATE_UNKNOWN
Wi-Fi is in an unknown state. 未知 网卡状态
This state will occur when an error happens while enabling or disabling.
Constant Value(常量值): 4 (0x00000004)
<3>操作WI-FI的所需的权限
可以在帮助文档里找到详细的权限,这里只列出一部分。
Manifest.permission(权限)
public static final String CHANGE_WIFI_MULTICAST_STATE
Allows applications to enter Wi-Fi Multicast mode
Constant Value: "android.permission.CHANGE_WIFI_MULTICAST_STATE"
public static final String CHANGE_WIFI_STATE
Allows applications to change Wi-Fi connectivity state
Constant Value: "android.permission.CHANGE_WIFI_STATE"
public static final String CHANGE_NETWORK_STATE
Allows applications to change network connectivity state
Constant Value: "android.permission.CHANGE_NETWORK_STATE
<4>改变WI-FI网卡的状态
对WI-FI网卡进行操作需要通过WifiManager对象进行
WifiManager wifiManager = (WifiManager) this.getSystemService(Context.WIFI_SERVICE);
打开WI-FI网卡
wifiManager.setWifiEnabled(true);
关闭WI-FI网卡
wifiManager.setWifiEnabled(false);
获取网卡当前状态
wifiManager..getWifiState()
package mars.wifi;
import android.app.Activity;
import android.content.Context;
import android.net.wifi.WifiManager;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;
public class WifiActivity extends Activity {
/** Called when the activity is first created. */
private Button startButton = null;
private Button stopButton = null;
private Button checkButton = null;
private WifiManager wifiManager = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
startButton = (Button)findViewById(R.id.startWifi);
stopButton = (Button)findViewById(R.id.stopWifi);
checkButton = (Button)findViewById(R.id.checkWifi);
startButton.setOnClickListener(new StartWifiListener());
stopButton.setOnClickListener(new StopWifiListener());
checkButton.setOnClickListener(new CheckWifiListener());
}
class StartWifiListener implements OnClickListener{
public void onClick(View v) {
wifiManager = (WifiManager)WifiActivity.this.getSystemService(Context.WIFI_SERVICE);
wifiManager.setWifiEnabled(true);
补充:移动开发 , Android ,