自由手記

1.修改JAVA

package android.wifi;

import java.util.List;

import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.net.wifi.ScanResult;
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.TextView;

public class WifiActivity extends Activity implements OnClickListener {
 private TextView tv_search_result;
 private WifiManager wifi_mng;
 private WifiReceiver wifi_rec;

 /** Called when the activity is first created. */
 @Override
 public void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.main);
  Button btn_start_search = (Button) findViewById(R.id.btn_start_search);
  btn_start_search.setOnClickListener(this);
 }

 public void onClick(View v) {
  if (v.getId() == R.id.btn_start_search) {
   tv_search_result = (TextView) findViewById(R.id.tv_search_result);
   wifi_mng = (WifiManager) getSystemService(Context.WIFI_SERVICE);
   wifi_rec = new WifiReceiver();
   registerReceiver(wifi_rec, new IntentFilter(
     WifiManager.SCAN_RESULTS_AVAILABLE_ACTION));
   wifi_mng.startScan();
   tv_search_result.setText("檢索開始\n");
  }
 }

 class WifiReceiver extends BroadcastReceiver {

  @Override
  public void onReceive(Context context, Intent intent) {
   StringBuffer sb = new StringBuffer();
   List<ScanResult> result_list = wifi_mng.getScanResults();
   for (int i = 0; i < result_list.size(); i++) {
    sb.append(new Integer(i + 1).toString() + ".");
    sb.append((result_list.get(i)).toString());
    sb.append("\n");
   }
   tv_search_result.setText(sb);
  }
 }
}

2.修改AndroidManifext.xml

<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"></uses-permission>
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE"></uses-permission>