android - wifimanager.calculatesignalstrenth 问题

Question

我正在使用以下代码来计算 wifi 信号强度:

List<ScanResult> results = wifiDemo.wifi.getScanResults();

for(int i=0;i<results.size();i++)
{    
    int signallevel=WifiManager.calculateSignalLevel(result.level,10);    
}

但它为所有 wifi 接入点返回相同的值。谁能告诉我我做错了什么？

Answer 1

代码如下:

public int getWifiSignalState(Context ctx) {
    int signalStrength = -1;
    try {
        final WifiManager wifi = (WifiManager) ctx.getSystemService(Context.WIFI_SERVICE);
        int state = wifi.getWifiState();
        if(state == WifiManager.WIFI_STATE_ENABLED) {
            List<ScanResult> results = wifi.getScanResults();
            if(results == null)
                return signalStrength;
            for (ScanResult result : results) {
                if(result != null && wifi != null && wifi.getConnectionInfo() != null && result.BSSID != null
                        && result.BSSID.equals(wifi.getConnectionInfo().getBSSID())) {
                    int level = 0;
                    level = calculateSignalLevel(wifi.getConnectionInfo().getRssi(), result.level);

                    // this is to handle java.lang.ArithmeticException: divide by zero
                    if(level != 0 && result.level != 0) {
                        // convert signal strength into percentage
                        int difference = level * 100 / result.level;
                        if(difference >= 100)
                            signalStrength = 4;
                        else if(difference >= 75)
                            signalStrength = 3;
                        else if(difference >= 50)
                            signalStrength = 2;
                        else if(difference >= 25)
                            signalStrength = 1;
                    }
                }

            }
        }
    } catch(Exception e) {
        ErrorReporter.handleSilentException(ctx, e);
    }

    return signalStrength;
}

//此方法修复android 2.3除以零异常的问题

public int calculateSignalLevel(int rssi, int numLevels) {
    if(rssi <= MIN_RSSI) {
        return 0;
    } else if(rssi >= MAX_RSSI) {
        return numLevels - 1;
    } else {
        float inputRange = (MAX_RSSI - MIN_RSSI);
        float outputRange = (numLevels - 1);
        if(inputRange != 0)
            return (int) ((float) (rssi - MIN_RSSI) * outputRange / inputRange);
    }
    return 0;
}