【Android13开发WIFI添加频段设置项(2.4G/5G/automatic)更改笔记】

这篇具有很好参考价值的文章主要介绍了【Android13开发WIFI添加频段设置项(2.4G/5G/automatic)更改笔记】。希望对大家有所帮助。如果存在错误或未考虑完全的地方,请大家不吝赐教,您也可以点击"举报违法"按钮提交疑问。

BUG需求描述:

提示:这里简述项目相关背景:

Android13中客户需求添加WIFI频段选项:
2.4G only,只显示链接2.4G的AP。
5G only,只能显示和链接5G的AP。
Automatic:自动显示,即全部正常显示。

解决初衷

提示:这里描述项目中遇到的问题:

作为初学者的我,刚开始接到这个bug,还是比较懵的,多亏了CSDN的前辈发表的文章给予我很大的帮助。站在巨人的肩膀上看的更远,我在前辈的文章上进一步添加自己的理解,剖析其中的逻辑,希望能给大家提供帮助!

你需要具备有关WIFI的一点小知识

1.android wifi scanresult.接口
ScanResult类实现Parcelable接口:ScanResult类描述了一个已发现AP的信息。除了在该类中描述的属性,supplicant还跟踪了quality(品质),noise(噪声),maxbitrate(最大比特率)属性,但是并不立刻将它们通知给客户端。
2.1.目录位置:
/frameworks/base/wifi/java/android/net/wifi/

3.WIFI频段中24G和5G核心方法
1.public boolean is24GHz():直接调用is24GHz(frequency),即用自己的信道频率值进行判断,如果频率值在2400~2500之间,(不包括2400和2500两个边界值),则返回true,否则返回false。

2.public boolean is5GHz(int freq):用传入的freq值进行判断,若在4900~5900之间,不含边界,则返回true,否则返回false。

更改后的样式展示

【Android13开发WIFI添加频段设置项(2.4G/5G/automatic)更改笔记】,Android开发笔记,android,java,需求分析
【Android13开发WIFI添加频段设置项(2.4G/5G/automatic)更改笔记】,Android开发笔记,android,java,需求分析

实现思路

设置页面里使用ListPreference静态增加"WLAN频段"菜单项,通过选项将设定的wifi频段值保存在settings数据库中,最后在WifiManager里处理其中的逻辑。

代码实现步骤(保姆式教学):

1.首先第一步骤需要在相应的布局位置添加相应的布局。
system/vendor/mediatek/proprietary/packages/apps/MtkSettings/res/xml/wifi_configure_settings.xml

资源文件需在strings.xml中单独配置

<ListPreference
        android:key="wifi_frequency_options"
        android:title="@string/wifi_frequency_options_title"//需要自己去string.xml中定义
        android:summary="@string/wifi_frequency_options_summary"//需要自己去string.xml中定义
        android:negativeButtonText="@android:string/cancel"
        android:persistent="false"
        android:entries="@array/wifi_frequency_options_entries"
        android:entryValues="@array/wifi_frequency_options_values"
        settings:controller="com.android.settings.wifi.WifiFrequencyBandPreferenceController"/>

布局页面位置
【Android13开发WIFI添加频段设置项(2.4G/5G/automatic)更改笔记】,Android开发笔记,android,java,需求分析


2.vendor/mediatek/proprietary/packages/apps/MtkSettings/res/values/arrays.xml
添加相应的数组和添加相应的选项

<string-array name="wifi_frequency_options_entries">
        <item>Automatic</item>
        <item>2.4 GHz only</item>
        <item>5 GHz only</item>
    </string-array>

    <string-array name="wifi_frequency_options_values">
        <item>2</item>
        <item>1</item>
        <item>0</item>
    </string-array>

参考文章添加位置
【Android13开发WIFI添加频段设置项(2.4G/5G/automatic)更改笔记】,Android开发笔记,android,java,需求分析

3.新增控制文件
system/vendor/mediatek/proprietary/packages/apps/MtkSettings/src/com/android/settings/wifi/WifiFrequencyBandPreferenceController.java

package com.android.settings.wifi;

import android.content.Context;
import android.net.wifi.WifiManager;
import android.provider.Settings;
import android.util.Log;
import androidx.preference.ListPreference;
import androidx.preference.Preference;
import androidx.preference.PreferenceScreen;
import com.android.settings.core.PreferenceControllerMixin;
import com.android.settingslib.core.AbstractPreferenceController;
import com.android.settingslib.core.lifecycle.Lifecycle;
import com.xchengtech.ProjectConfig;

public class WifiFrequencyBandPreferenceController extends AbstractPreferenceController implements PreferenceControllerMixin, Preference.OnPreferenceChangeListener {
    private static Context mContext;
    private WifiManager mWifiManager;

    public String getPreferenceKey() {
        return "wifi_frequency_options";
    }

    public boolean isAvailable() {
        return true; //可以设置相应宏控判定该模块是否呈现
    }

    public WifiFrequencyBandPreferenceController(Context context, Lifecycle lifecycle, WifiManager wifiManager) {
        super(context);
        mContext = context;
        this.mWifiManager = wifiManager;
    }

    public void displayPreference(PreferenceScreen preferenceScreen) {
        super.displayPreference(preferenceScreen);
        ListPreference listPreference = (ListPreference) preferenceScreen.findPreference("wifi_frequency_options");
        int frequencyBand = getFrequencyBand();
        listPreference.setValue("" + frequencyBand);
        updateFrequencyBandSummary(listPreference, "" + frequencyBand);
    }

    public boolean onPreferenceChange(Preference preference, Object obj) {
        String str = (String) obj;
        int parseInt = Integer.parseInt(str);
        updateFrequencyBandSummary((ListPreference) preference, str);
        boolean b = Settings.Global.putInt(mContext.getContentResolver(), "wifi_frequency_band", parseInt);
        if (b) {
            if (null != mWifiManager) {
                if (mWifiManager.isWifiEnabled()) {
                    mWifiManager.setWifiEnabled(false);
                    mWifiManager.setWifiEnabled(true);
                }else{
                    mWifiManager.setWifiEnabled(true);
                    mWifiManager.setWifiEnabled(false);
                }
            }
        }
        return true;
    }

    private int getFrequencyBand() {
        return Settings.Global.getInt(mContext.getContentResolver(), "wifi_frequency_band", 2);
    }

    private void updateFrequencyBandSummary(ListPreference listPreference, String str) {
        listPreference.setSummary(listPreference.getEntries()[listPreference.findIndexOfValue(str)]);
    }
}

4.在WIFI设置项中的控制类添加相应的控制模块
system/vendor/mediatek/proprietary/packages/apps/MtkSettings/src/com/android/settings/wifi/ConfigureWifiSettings.java

    @Override
    protected List<AbstractPreferenceController> createPreferenceControllers(Context context) {
        final WifiManager wifiManager = (WifiManager) getSystemService(WIFI_SERVICE);
        final List<AbstractPreferenceController> controllers = new ArrayList<>();
        controllers.add(new WifiP2pPreferenceController(context, getSettingsLifecycle(),
                wifiManager));
        /// M: For wapi cert manager feature @{
        controllers.add(new WapiCertPreferenceController(context));
        /// @}

        //add by wjj for wifi frequency options  start
        controllers.add(new WifiFrequencyBandPreferenceController(context, getSettingsLifecycle(), wifiManager));
        //add by wjj for wifi frequency options  end
        return controllers;
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);

5.核心逻辑实现类在wifimanager.java类中的getScanResults()方法中
首先现在最上方设置相应的宏定义
system/packages/modules/Wifi/framework/java/android/net/wifi/WifiManager.java

	//wjj add
	final int wifi_band_5_ghz = 0;
	final int wifi_band_24_ghz = 1;
	final int wifi_band_5_24ghz = 2;
	//wjj end

再在相应的方法中添加相应的判断逻辑

    /**
     * Return the results of the latest access point scan.
     * @return the list of access points found in the most recent scan. An app must hold
     * {@link android.Manifest.permission#ACCESS_FINE_LOCATION ACCESS_FINE_LOCATION} permission
     * and {@link android.Manifest.permission#ACCESS_WIFI_STATE} permission
     * in order to get valid results.
     */
    @RequiresPermission(allOf = {ACCESS_WIFI_STATE, ACCESS_FINE_LOCATION})
    public List<ScanResult> getScanResults() {
        try {
            //add by wjj for wifi frequency options start
                if (true) { //此处可以进一步设置判断
                    List<ScanResult> results = mService.getScanResults(mContext.getOpPackageName(),mContext.getAttributionTag()); //设置scanResult类型的列表 result 获取每一条wifi字段包含许多属性
                    int wifiFrequency = Settings.Global.getInt(mContext.getContentResolver(), "wifi_frequency_band", 2); //wifiFrequency 只获取其中的频段
                    if(results != null && results.size() > 0){//判空逻辑,列表不为空则进行下一步
                        WifiInfo wifiInfo = getConnectionInfo();//获取所有可以链接的项(我的理解)
                        Iterator<ScanResult> iterator = results.iterator();//迭代器进行遍历
                        while (iterator.hasNext()) {//迭代器结果判断
                            ScanResult result = iterator.next();
                            if(ScanResult.is24GHz(result.frequency) && (wifiFrequency == wifi_band_5_ghz)){//异常值即频段只有2.4G但band等级达到5G的异常值(不是很懂怎么表述,希望大佬指正)意思大概就是异常值移除
                                iterator.remove();//移除操作
                                if (ScanResult.is24GHz(wifiInfo.getFrequency())) {//符合2.4G
                                    disableEphemeralNetwork(wifiInfo.getSSID());//隐藏相应的显示信息
                                    disconnect();//断开链接
                                }
                            }
                            if((ScanResult.is5GHz(result.frequency) || result.frequency >= 5900 )
                                    && (wifiFrequency == wifi_band_24_ghz)){//符合5G频段或6G但wifi等级却是2.4G的异常值移除
                                iterator.remove();
                                if (ScanResult.is5GHz(wifiInfo.getFrequency()) || result.frequency >= 5900) {//符合5G或以上条件的
                                    disableEphemeralNetwork(wifiInfo.getSSID());//隐藏
                                    disconnect();//断开链接
                                }
                            }
                        }
                    }
                    return results;
                } else {//扫描结果全部进行显示
                    return mService.getScanResults(mContext.getOpPackageName(),
                            mContext.getAttributionTag());
                }
            //add by wjj for wifi frequency options end
        } catch (RemoteException e) {//异常处理
            throw e.rethrowFromSystemServer();
        }
    }

Bug优化1:解决wifi频率切换时,有时不会自动断开或重新连接
1.system/packages/modules/Wifi/service/java/com/android/server/wifi/WifiConnectivityManager.java

/**
     * Handles 'onResult' callbacks for the Periodic, Single & Pno ScanListener.
     * Executes selection of potential network candidates, initiation of connection attempt to that
     * network.
     */
    private void handleScanResults(@NonNull List<ScanDetail> scanDetails,
            @NonNull String listenerName,
            boolean isFullScan,
            @NonNull HandleScanResultsListener handleScanResultsListener) {

        //add by wjj for wifi frequency options start
            Iterator<ScanDetail> iterator = scanDetails.iterator();
            int wifi_frequency_band = Settings.Global.getInt(mContext.getContentResolver(), "wifi_frequency_band", 2);
            while (iterator.hasNext()) {
                ScanDetail result = iterator.next();
                ScanResult sr = result.getScanResult();
                if ((!ScanResult.is24GHz(sr.frequency) && (wifi_frequency_band == wifi_band_24_ghz))
                        || (!ScanResult.is5GHz(sr.frequency) && wifi_frequency_band == wifi_band_5_ghz)) {
                    iterator.remove();
                }
            }
        //add by wjj for wifi frequency options end
List<WifiNetworkSelector.ClientModeManagerState> cmmStates = new ArrayList<>();
        Set<String> connectedSsids = new HashSet<>();
        boolean hasExistingSecondaryCmm = false;
        for (ClientModeManager clientModeManager :
                mActiveModeWarden.getInternetConnectivityClientModeManagers()) {
            if (clientModeManager.getRole() == ROLE_CLIENT_SECONDARY_LONG_LIVED) {
                hasExistingSecondaryCmm = true;
            }
            mWifiChannelUtilization.refreshChannelStatsAndChannelUtilization(
                    clientModeManager.getWifiLinkLayerStats(),
                    WifiChannelUtilization.UNKNOWN_FREQ);
            WifiInfo wifiInfo = clientModeManager.syncRequestConnectionInfo();
            if (clientModeManager.isConnected()) {
                connectedSsids.add(wifiInfo.getSSID());
            }
            cmmStates.add(new WifiNetworkSelector.ClientModeManagerState(clientModeManager));
        }
        // We don't have any existing secondary CMM, but are we allowed to create a secondary CMM
        // and do we have a request for OEM_PAID/OEM_PRIVATE request? If yes, we need to perform
        // network selection to check if we have any potential candidate for the secondary CMM
        // creation.
        if (!hasExistingSecondaryCmm
                && (mOemPaidConnectionAllowed || mOemPrivateConnectionAllowed)) {
            // prefer OEM PAID requestor if it exists.
            WorkSource oemPaidOrOemPrivateRequestorWs =
                    mOemPaidConnectionRequestorWs != null
                            ? mOemPaidConnectionRequestorWs
                            : mOemPrivateConnectionRequestorWs;
            if (oemPaidOrOemPrivateRequestorWs == null) {
                Log.e(TAG, "Both mOemPaidConnectionRequestorWs & mOemPrivateConnectionRequestorWs "
                        + "are null!");
            }
            if (oemPaidOrOemPrivateRequestorWs != null
                    && mActiveModeWarden.canRequestMoreClientModeManagersInRole(
                            oemPaidOrOemPrivateRequestorWs,
                            ROLE_CLIENT_SECONDARY_LONG_LIVED, false)) {
                // Add a placeholder CMM state to ensure network selection is performed for a
                // potential second STA creation.
                cmmStates.add(new WifiNetworkSelector.ClientModeManagerState());
                hasExistingSecondaryCmm = true;
            }
        }

2.自己添加的控制类中完善
system/vendor/mediatek/proprietary/packages/apps/MtkSettings/src/com/android/settings/wifi/WifiFrequencyBandPreferenceController.java

    public boolean onPreferenceChange(Preference preference, Object obj) {
        String str = (String) obj;
        int parseInt = Integer.parseInt(str);
        updateFrequencyBandSummary((ListPreference) preference, str);
        boolean b = Settings.Global.putInt(mContext.getContentResolver(), "wifi_frequency_band", parseInt);
        if (b) {
            if (null != mWifiManager) {
                if (mWifiManager.isWifiEnabled()) {
                    mWifiManager.setWifiEnabled(false);
                    mWifiManager.setWifiEnabled(true);
                    //add by wjj for wifi frequency options  start
                    mWifiManager.startScan();
                    //add by wjj for wifi frequency options  end
                }else{
                    mWifiManager.setWifiEnabled(true);
                    mWifiManager.setWifiEnabled(false);
                }
            }
        }
        return true;
    }

Bug优化2:这个是前辈优化步骤值得借鉴
对于双频合一的wifi优化:android13中如果未对双频wifi优化,当选择2.4g频段时,连接双频合一wifi,此wifi不是2.4g频率(还是5g频率),正常现象应该是连上双频合一wifi2.4g频率的。

    public boolean startSingleScan(WifiNative.ScanSettings settings,
            WifiNative.ScanEventHandler eventHandler) {
        if (eventHandler == null || settings == null) {
            Log.w(TAG, "Invalid arguments for startSingleScan: settings=" + settings
                    + ",eventHandler=" + eventHandler);
            return false;
        }
        synchronized (mSettingsLock) {
            if (mLastScanSettings != null) {
                Log.w(TAG, "A single scan is already running");
                return false;
            }

            ChannelCollection allFreqs = mChannelHelper.createChannelCollection();


            boolean reportFullResults = false;

            for (int i = 0; i < settings.num_buckets; ++i) {
                WifiNative.BucketSettings bucketSettings = settings.buckets[i];
                if ((bucketSettings.report_events
                                & WifiScanner.REPORT_EVENT_FULL_SCAN_RESULT) != 0) {
                    reportFullResults = true;
                }
                allFreqs.addChannels(bucketSettings);
            }

            List<String> hiddenNetworkSSIDSet = new ArrayList<>();
            if (settings.hiddenNetworks != null) {
                boolean executeRoundRobin = true;
                int maxNumScanSsids = mMaxNumScanSsids;
                if (maxNumScanSsids <= 0) {
                    // Subtract 1 to account for the wildcard/broadcast probe request that
                    // wificond adds to the scan set.
                    mMaxNumScanSsids = mWifiNative.getMaxSsidsPerScan(getIfaceName()) - 1;
                    if (mMaxNumScanSsids > 0) {
                        maxNumScanSsids = mMaxNumScanSsids;
                    } else {
                        maxNumScanSsids = DEFAULT_NUM_HIDDEN_NETWORK_IDS_PER_SCAN;
                        executeRoundRobin = false;
                    }
                }
                int numHiddenNetworksPerScan =
                        Math.min(settings.hiddenNetworks.length, maxNumScanSsids);
                if (numHiddenNetworksPerScan == settings.hiddenNetworks.length
                        || mNextHiddenNetworkScanId >= settings.hiddenNetworks.length
                        || !executeRoundRobin) {
                    mNextHiddenNetworkScanId = 0;
                }
                if (DBG) {
                    Log.d(TAG, "Scanning for " + numHiddenNetworksPerScan + " out of "
                            + settings.hiddenNetworks.length + " total hidden networks");
                    Log.d(TAG, "Scan hidden networks starting at id=" + mNextHiddenNetworkScanId);
                }

                int id = mNextHiddenNetworkScanId;
                for (int i = 0; i < numHiddenNetworksPerScan; i++, id++) {
                    hiddenNetworkSSIDSet.add(
                            settings.hiddenNetworks[id % settings.hiddenNetworks.length].ssid);
                }
                mNextHiddenNetworkScanId = id % settings.hiddenNetworks.length;
            }
            mLastScanSettings = new LastScanSettings(
                    mClock.getElapsedSinceBootNanos(),
                    reportFullResults, allFreqs, eventHandler);

            boolean success = false;
            Set<Integer> freqs = Collections.emptySet();

            //add by ysliu 2023.9.28 start
            //Set<Integer> freqs;
            final int wifi_band_5_ghz = 0;
            final int wifi_band_24_ghz = 1;
            final int wifi_band_5_24ghz = 2;
            int[] channels = null;
            int[] channelDfs = null;
            int frequencyBand = Settings.Global.getInt(mContext.getContentResolver(), "wifi_frequency_band", 2);
            Log.d(TAG, "Ap_Frequency_Band = " + frequencyBand);
            if (!allFreqs.isEmpty()) {
                //freqs = allFreqs.getScanFreqs();
                ArraySet<Integer> mChannels = new ArraySet<Integer>();
                switch (frequencyBand) {
                    case wifi_band_24_ghz:
                        channels = mWifiNative.getChannelsForBand(WifiScanner.WIFI_BAND_24_GHZ);
                        break;
                    case wifi_band_5_ghz:
                        channels = mWifiNative.getChannelsForBand(WifiScanner.WIFI_BAND_5_GHZ);
                        channelDfs = mWifiNative.getChannelsForBand(WifiScanner.WIFI_BAND_5_GHZ_DFS_ONLY);
                        break;
                    default:
                        break;
                }
                if (null != channels) {
                    for (int chan : channels) {
                        mChannels.add(chan);
                    }
                    if (null != channelDfs) {
                        for (int chan : channelDfs) {
                            mChannels.add(chan);
                        }
                    }
                    freqs = new ArraySet<Integer>(mChannels);
                } else {
                    freqs = allFreqs.getScanFreqs();
                }
                Log.d(TAG, "freqs=" + freqs);
                //add by ysliu 2023.9.28 end

                if (!allFreqs.isEmpty()) {
                    // freqs = allFreqs.getScanFreqs(); //modify by ysliu 2023.9.28 
                    success = mWifiNative.scan(
                            getIfaceName(), settings.scanType, freqs, hiddenNetworkSSIDSet,
                            settings.enable6GhzRnr);
                    if (!success) {
                        Log.e(TAG, "Failed to start scan, freqs=" + freqs);
                    }
                } else {
                    // There is a scan request but no available channels could be scanned for.
                    // We regard it as a scan failure in this case.
                    Log.e(TAG, "Failed to start scan because there is no available channel to scan");
                }
                if (success) {
                    if (DBG) {
                        Log.d(TAG, "Starting wifi scan for freqs=" + freqs
                                + " on iface " + getIfaceName());
                    }

                    mScanTimeoutListener = new AlarmManager.OnAlarmListener() {
                        @Override
                        public void onAlarm() {
                            handleScanTimeout();
                        }
                    };

                    mAlarmManager.set(AlarmManager.ELAPSED_REALTIME_WAKEUP,
                            mClock.getElapsedSinceBootMillis() + SCAN_TIMEOUT_MS,
                            TIMEOUT_ALARM_TAG, mScanTimeoutListener, mEventHandler);
                } else {
                    // indicate scan failure async
                    mEventHandler.post(() -> reportScanFailure());
                }
            }
            return true;
        }
    }

总结:

1.Android 10 或更高版本为目标平台的应用调用WifiManager相关api(setWifiEnable、startScan、getScanResults等方法)不会生效,会返回false
2.调用Wi-Fi信息需要以下权限
添加位置在settings的菜单文件中(一般都有加)

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


最后的总结:

伙伴们,我是参考一位叫ysliu的前辈的,在他的基础上进行进一步的补充,作为刚入职场的人来说,太需要这样板书十分仔细的前辈了,如果您看到这里啦,可以再去看看前辈写的东西,真的很详细 前辈的CSDN。希望我记录的这些东西能够帮助到更多的人吧!–一位初入职场大学学大数据的android开发从业者。

前辈更多优秀文章的链接(上方超链接也可以哈):

Lysssx前辈文章来源地址https://www.toymoban.com/news/detail-753069.html

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