无线扫描结果广播接收器不工作

本文介绍了无线扫描结果广播接收器不工作的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我写了一个简单的广播接收器显示敬酒消息时完成无线扫描。没有什么是显示。这里是我的code：

包com.wifi;进口的java.util.List;进口android.content.BroadcastReceiver;进口android.content.Context;进口android.content.Intent;进口android.wifi.ScanResult;进口android.wifi.WifiManager;进口android.widget.Toast;公共类wifiReceiver扩展广播接收器{    @覆盖    公共无效的onReceive（上下文的背景下，意图意图）{        Toast.makeText（上下文中，扫描完成，Toast.LENGTH_LONG）.show（）;    }}

下面是清单文件：

＆LT;？XML版本=1.0编码=UTF-8＆GT？;＆LT;清单的xmlns：机器人=htt​​p://schemas.android/apk/res/android      包=com.wifi      安卓版code =1      机器人：=的versionName1.0＆GT;    ＆lt;应用机器人：图标=@绘制/图标机器人：标签=@字符串/ APP_NAME＆GT;        ＆LT;活动机器人：无线NAME =机器人：标签=@字符串/ APP_NAME＆GT;            ＆所述;意图滤光器＆gt;                ＆lt;作用机器人：名字=android.intent.action.MAIN/＆GT;                ＆LT;类机器人：名字=android.intent.category.LAUNCHER/＆GT;            ＆所述; /意图滤光器＆gt;        ＆LT; /活性GT;    ＆lt;接收机器人：名字=。wifiReceiver＆GT;        ＆所述;意图滤光器＆gt;            ＆lt;作用机器人：名字=android.wifi.SCAN_RESULTS＆GT;＆LT; /作用＆gt;        ＆所述; /意图滤光器＆gt;    ＆LT; /接收器＆GT;    ＆LT; /用途＆gt;    ＆LT;使用许可权的android：NAME =android.permission.ACCESS_WIFI_STATE/＆GT;    ＆LT;使用许可权的android：NAME =android.permission.CHANGE_WIFI_STATE/＆GT;＆LT; /清单＆GT;

解决方案

好，这不是那么容易;-)结果有几件事情失踪...这里是一个WiFi扫描的一个例子 - 原始来源$ C ​​$ C在这里www.androidsnippets/scan-for-wireless-networks

包com.android.wifitester;进口的java.util.List;进口android.app.Activity;进口android.content.BroadcastReceiver;进口android.content.Context;进口android.content.Intent;进口android.content.IntentFilter;进口android.wifi.ScanResult;进口android.wifi.WifiManager;进口android.os.Bundle;进口android.view.Menu;进口android.view.MenuItem;进口android.widget.TextView;公共类WifiTester延伸活动{TextView中的mainText;WifiManager mainWifi;WifiReceiver receiverWifi;清单＆LT; ScanResult＆GT; wifiList;StringBuilder的SB =新的StringBuilder（）;公共无效的onCreate（捆绑savedInstanceState）{   super.onCreate（savedInstanceState）;   的setContentView（R.layout.main）;   的mainText =（的TextView）findViewById（R.id.mainText）;   mainWifi =（WifiManager）getSystemService（Context.WIFI_SERVICE）;   receiverWifi =新WifiReceiver（）;   registerReceiver（receiverWifi，新的IntentFilter（WifiManager.SCAN_RESULTS_AVAILABLE_ACTION））;   mainWifi.startScan（）;   mainText.setText（\\\\ n起始扫描... \\\\ N）;}公共布尔onCreateOptionsMenu（菜单菜单）{    menu.add（0，0，0，刷新）;    返回super.onCreateOptionsMenu（菜单）;}公共布尔onMenuItemSelected（INT FEATUREID，菜单项项）{    mainWifi.startScan（）;    mainText.setText（开始扫描）;    返回super.onMenuItemSelected（FEATUREID，项目）;}保护无效的onPause（）{    unregisterReceiver（receiverWifi）;    super.onPause（）;}保护无效onResume（）{    registerReceiver（receiverWifi，新的IntentFilter（WifiManager.SCAN_RESULTS_AVAILABLE_ACTION））;    super.onResume（）;}类WifiReceiver扩展广播接收器{    公共无效的onReceive（上下文C，意图意图）{        SB =新的StringBuilder（）;        wifiList = mainWifi.getScanResults（）;        的for（int i = 0; I＆LT; wifiList.size（）;我++）{            sb.append（新整数第（i + 1）的ToString（）+。）;            sb.append（（wifiList.get（I））的toString（））;            sb.append（\\\\ N）;        }        mainText.setText（某人）;    }}}

I have written a simple broadcast receiver to show a toast message when wifi scan is completed. Nothing is showing. Here is my code:

package com.wifi; import java.util.List; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.wifi.ScanResult; import android.wifi.WifiManager; import android.widget.Toast; public class wifiReceiver extends BroadcastReceiver { @Override public void onReceive(Context context, Intent intent) { Toast.makeText(context,"Scan completed", Toast.LENGTH_LONG).show(); } }

Here is the manifest file:

<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="schemas.android/apk/res/android" package="com.wifi" android:versionCode="1" android:versionName="1.0"> <application android:icon="@drawable/icon" android:label="@string/app_name"> <activity android:name=".wifi" android:label="@string/app_name"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <receiver android:name=".wifiReceiver"> <intent-filter> <action android:name="android.wifi.SCAN_RESULTS"></action> </intent-filter> </receiver> </application> <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" /> <uses-permission android:name="android.permission.CHANGE_WIFI_STATE" /> </manifest>

解决方案

well, it's not that easy ;-) there are couple of things missing... here is an example of a wifi scan - the original source code is located here www.androidsnippets/scan-for-wireless-networks

package com.android.wifitester; 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.wifi.ScanResult; import android.wifi.WifiManager; import android.os.Bundle; import android.view.Menu; import android.view.MenuItem; import android.widget.TextView; public class WifiTester extends Activity { TextView mainText; WifiManager mainWifi; WifiReceiver receiverWifi; List<ScanResult> wifiList; StringBuilder sb = new StringBuilder(); public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); mainText = (TextView) findViewById(R.id.mainText); mainWifi = (WifiManager) getSystemService(Context.WIFI_SERVICE); receiverWifi = new WifiReceiver(); registerReceiver(receiverWifi, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION)); mainWifi.startScan(); mainText.setText("\\nStarting Scan...\\n"); } public boolean onCreateOptionsMenu(Menu menu) { menu.add(0, 0, 0, "Refresh"); return super.onCreateOptionsMenu(menu); } public boolean onMenuItemSelected(int featureId, MenuItem item) { mainWifi.startScan(); mainText.setText("Starting Scan"); return super.onMenuItemSelected(featureId, item); } protected void onPause() { unregisterReceiver(receiverWifi); super.onPause(); } protected void onResume() { registerReceiver(receiverWifi, new IntentFilter(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION)); super.onResume(); } class WifiReceiver extends BroadcastReceiver { public void onReceive(Context c, Intent intent) { sb = new StringBuilder(); wifiList = mainWifi.getScanResults(); for(int i = 0; i < wifiList.size(); i++){ sb.append(new Integer(i+1).toString() + "."); sb.append((wifiList.get(i)).toString()); sb.append("\\n"); } mainText.setText(sb); } } }