設定速度計快訊

啟用導航功能並將交通方式設為開車時，iOS 版 Navigation SDK 會在地圖左下角顯示速限控制項，顯示目前的速限。如果駕駛人超過速限，控制項會展開，在速限顯示旁邊顯示計速器，並在速度達到特定門檻時觸發警報。

根據預設，如果駕駛人超過速限 5 英里/時 (或 10 公里/時)，Navigation SDK 就會觸發輕微的速度警示，並將速度計文字的顏色變更為紅色。如果駕駛人超速 10 英里/時 (或 20 公里/時)，系統就會觸發重大超速警示，並將速度計背景顏色變更為紅色。

您可以自訂觸發快訊的門檻，以及速度計顯示的文字和背景顏色。您也可以使用 Navigation SDK 提供駕駛人的車速資訊。舉例來說，您可以向共乘服務業者提供車速資訊，協助他們鼓勵駕駛人遵守速限，進而提升安全性。

自訂速度快訊的門檻

您可以自訂輕微和重大超速警示的速限百分比，您也可以指定地圖顯示快訊前，超出門檻的時間長度。

下列程式碼範例會將輕微超速警示的門檻設為超過速限 5%，嚴重超速警示的門檻則設為超過速限 10%。這項設定指定地圖在警示閾值超過五秒後顯示警示。

Swift

let minorSpeedAlertThresholdPercentage: CGFloat = 0.05 let
majorSpeedAlertThresholdPercentage: CGFloat = 0.1 let
severityUpgradeDurationSeconds: TimeInterval = 5

// Configure SpeedAlertOptions let mutableSpeedAlertOptions:
GMSNavigationMutableSpeedAlertOptions = GMSNavigationMutableSpeedAlertOptions()
 mutableSpeedAlertOptions.setSpeedAlertThresholdPercentage(minorSpeedAlertThresholdPercentage,
for: .minor)
mutableSpeedAlertOptions.setSpeedAlertThresholdPercentage(majorSpeedAlertThresholdPercentage,
for: .major) mutableSpeedAlertOptions.severityUpgradeDurationSeconds =
severityUpgradeDurationSeconds

// Set SpeedAlertOptions to Navigator. mapView.navigator?.speedAlertOptions =
mutableSpeedAlertOptions; mapView.navigator?.add(self); // Only needed if
listening to the delegate events.

Objective-C

static const CGFloat minorSpeedAlertThresholdPercentage = 0.05; static const
CGFloat majorSpeedAlertThresholdPercentage = 0.1; static const NSTimeInterval
severityUpgradeDurationSeconds = 5;

// Configure SpeedAlertOptions GMSNavigationMutableSpeedAlertOptions
*mutableSpeedAlertOptions = [[GMSNavigationMutableSpeedAlertOptions alloc]
init]; [mutableSpeedAlertOptions setSpeedAlertThresholdPercentage:
minorSpeedAlertThresholdPercentage
forSpeedAlertSeverity:GMSNavigationSpeedAlertSeverityMinor];
[mutableSpeedAlertOptions
setSpeedAlertThresholdPercentage:majorSpeedAlertThresholdPercentage
forSpeedAlertSeverity:GMSNavigationSpeedAlertSeverityMajor];
[mutableSpeedAlertOptions
setSeverityUpgradeDurationSeconds:severityUpgradeDurationSeconds];

// Set SpeedAlertOptions to Navigator. mapView.navigator.speedAlertOptions =
mutableSpeedAlertOptions; [mapView.navigator addListener:self]; // Only needed
if listening to the delegate events.

自訂車速表顯示車速快訊的方式

你可以為每個警報等級自訂速度表顯示的顏色。

下表顯示 GMSNavigationSpeedometerUIOptions 類別中速限快訊的預設顏色：

元素顏色
MinorSpeedAlertBackgroundColorDayMode 0xffffff(白色)
MinorSpeedAlertBackgroundColorNightMode 0x000000
MinorSpeedAlertTextColorDayMode 0xd93025
MinorSpeedAlertTextColorNightMode 0xd93025
MajorSpeedAlertBackgroundColorDayMode 0xd93025
MajorSpeedAlertBackgroundColorNightMode 0xd93025
MajorSpeedAlertTextColorDayMode 0xffffff(白色)
MajorSpeedAlertTextColorNightMode 0xffffff(白色)

您可以為次要和主要速度快訊指定速度表的文字和背景顏色：

Swift

let mutableSpeedometerUIOptions: GMSNavigationMutableSpeedometerUIOptions =
GMSNavigationMutableSpeedometerUIOptions()
mutableSpeedometerUIOptions.setTextColor(minorSpeedAlertTextColor, for: .minor,
lightingMode: .normal)
mutableSpeedometerUIOptions.setTextColor(majorSpeedAlertTextColor, for: .major,
lightingMode: .normal)
mutableSpeedometerUIOptions.setBackgroundColor(minorSpeedAlertNightModeBackgroundColor,
for: .minor, lightingMode: .lowLight)
mutableSpeedometerUIOptions.setBackgroundColor(majorSpeedAlertDayModeBackgroundColor,
for: .major, lightingMode: .normal)

mapView.settings.speedometerUIOptions = mutableSpeedometerUIOptions

Objective-C

GMSNavigationMutableSpeedometerUIOptions *mutableSpeedometerUIOptions =
[[GMSNavigationMutableSpeedometerUIOptions alloc] init];
[mutableSpeedometerUIOptions setTextColor: minorSpeedAlertTextColor
forSpeedAlertSeverity: GMSNavigationSpeedAlertSeverityMinor lightingMode:
GMSNavigationLightingModeNormal]; [mutableSpeedometerUIOptions setTextColor:
majorSpeedAlertTextColor forSpeedAlertSeverity:
GMSNavigationSpeedAlertSeverityMajor lightingMode:
GMSNavigationLightingModeNormal]; [mutableSpeedometerUIOptions
setBackgroundColor: minorSpeedAlertNightModeBackgroundColor
forSpeedAlertSeverity: GMSNavigationSpeedAlertSeverityMinor lightingMode:
GMSNavigationLightingModeLowLight]; [mutableSpeedometerUIOptions
setBackgroundColor: majorSpeedAlertDayModeBackgroundColor forSpeedAlertSeverity:
GMSNavigationSpeedAlertSeverityMajor
lightingMode:GMSNavigationLightingModeNormal];

mapView.settings.speedometerUIOptions = mutableSpeedometerUIOptions;

接收駕駛人的速度資訊

如果應用程式需要分享駕駛人的車速資訊，您也可以使用 Navigation SDK 提供駕駛人的車速資訊。這項功能適用於共乘應用程式，因為營運人員可能想監控駕駛人是否超速，以提升安全性。

舉例來說，以下範例會在車速超過速限指定百分比時分享車速資訊：

Swift

// Listener method for sharing speed information when the speed exceeds the
speed limit by a specified percentage. #pragma mark GMSNavigatorListener func
navigator(_ navigator : GMSNavigator, didUpdateSpeedingPercentage
percentageAboveLimit : Float) { ... }

Objective-C

// Listener method listening to speeding feed. #pragma mark
GMSNavigatorListener - (void)navigator:(GMSNavigator *)navigator
didUpdateSpeedingPercentage:(float)percentageAboveLimit { ... }