施工中.....
Android權限設定
. . . . .
首先找到AndroidManifest.xml這個資料夾
在AndroidManifest.xml加入Wi-Fi讀取權限與更改Wi-Fi權限
介面設計
ScrollView語法
若是內容高度超過android:layout_height="?"的話 , 就會以滾動方式呈現
增加一段android:scrollbars="none"的話就不會顯示滾動條
程式碼
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 | <Button android:id="@+id/but1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="Search Wi-Fi" tools:ignore="MissingConstraints" tools:layout_editor_absoluteX="135dp" tools:layout_editor_absoluteY="447dp" /> <LinearLayout android:layout_width="wrap_content" android:layout_height="wrap_content" tools:layout_editor_absoluteX="16dp" tools:layout_editor_absoluteY="16dp"> <ScrollView android:id="@+id/scrollView" android:layout_width="wrap_content" android:layout_height="wrap_content"> <TextView android:id="@+id/text" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_gravity="center" android:text="WiFiDemo" /> </ScrollView> </LinearLayout> |
JAVA程式
this
一開始寫出來因為java原本沒有這個函數
這邊this是<普通的直接引用>
更多this,super用法 . . . .
BroadcastReceiver
通常廣播是用來通知系統
此範例中則是用來通知使用者沒開啟WIFI
這邊將它設為receiver然後在下面撰寫它的功能
super
程式碼
package com.example.user.wifi_2;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.IntentFilter;
import android.net.wifi.WifiConfiguration;
import android.net.wifi.WifiInfo;
import android.net.wifi.WifiManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;
import java.util.List;
import static com.example.user.wifi_2.R.id.info;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private static final String TAG="繃繃包"; WifiManager wifi; BroadcastReceiver receiver;
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 | TextView text; Button but; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); text=(TextView)findViewById(R.id.text); but=(Button)findViewById(R.id.but1); but.setOnClickListener(this); wifi=(WifiManager)getSystemService(Context.WIFI_SERVICE); WifiInfo info=wifi.getConnectionInfo(); text.append("\n\nwifi status ;"+info.toString()); List<WifiConfiguration> configurations=wifi.getConfiguredNetworks(); for(WifiConfiguration configuration :configurations){ text.append("\n\n" +configuration.toString()); } if(receiver==null) receiver=new WifiScaner(this); registerReceiver(receiver,new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION)); Log.d(TAG, "onCreate()"); } @Override public void onStop() { unregisterReceiver(receiver); super.onStop(); } @Override public void onClick(View view) { Toast.makeText(getApplicationContext(),"ALL WIFI seached~~",0).show(); if(view.getId()==R.id.but1){ Log.d(TAG, "onCreat() wifi.startScan()"); wifi.startScan(); } } |
}
接著對WifiScaner按alt+Enter寫立一個新的java檔
程式碼
package com.example.user.wifi_2;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.net.wifi.WifiManager;
import android.nfc.Tag;
import android.util.Log;
import android.widget.Toast;
import java.util.List;
class WifiScaner extends BroadcastReceiver {
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 | private static final String TAG="WifiscanReceiver"; MainActivity main; public WifiScaner(MainActivity mainActivity) { super(); this.main=main; } @Override public void onReceive(Context context, Intent intent) { List<android.net.wifi.ScanResult> results=main.wifi.getScanResults(); android.net.wifi.ScanResult bestsignal =null; for(android.net.wifi.ScanResult result:results){ if(bestsignal==null|| WifiManager.compareSignalLevel(bestsignal.level, result.level)<0) bestsignal=result; } String message=String.format("%s networks found.%s is the strongest.",results.size(), results.size(),bestsignal.SSID); Toast.makeText(main, message, 0).show(); Log.d(TAG, "onReceive() message :" +message); } |
}