啟用導航且將交通模式設為行車時，iOS 版 Navigation SDK 會在地圖左下角顯示速限控制項，當中顯示目前的速限。如果駕駛人超過速限，控制項會展開並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快訊。
根據預設，當駕駛人超過速限 (5 mph (或 10 公里)) 時，Navigation SDK 會觸發次要速度快訊，並將計速計文字的顏色變更為紅色。當駕駛人超過速限 10 mph (或 20 公里)，並將計速器背景顏色變更為紅色時，就會觸發重大速度警示。
您可以自訂觸發快訊的門檻，以及計速計顯示的文字和背景顏色。您也可以使用 Navigation SDK 提供驅動程式的速度資訊。舉例來說，您可以向代僱駕駛服務業者提供速度資訊，協助他們鼓勵駕駛遵守速限，並提高安全。
自訂速度快訊的門檻
您可以自訂小幅和主要速度快訊的速度快訊門檻，做為目前速度限制的百分比。您也可以指定超過門檻時，地圖顯示快訊的時間長度。
下列程式碼範例將次要速度快訊的門檻設為比速限的 5%，以及主要速度快訊的門檻設為比速限的 10%。指定在超過快訊門檻五秒後，地圖會顯示快訊。
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.
自訂計速器顯示速度快訊的方式
您可以自訂每個快訊等級的計速器顯示的顏色。
下表列出 GMSNavigationSpeedometerUIOptions 類別中速度快訊的預設顏色：
| 元素 | 顏色 |
|---|---|
| MinorSpeedAlertBackgroundColorDayMode | 0xffffff(白色) |
| MinorSpeedAlertBackgroundColorNightMode | 0x000000 |
| MinorSpeedAlertTextColorDayMode | 0 x 93025 |
| MinorSpeedAlertTextColorNightMode | 0 x 93025 |
| MajorSpeedAlertBackgroundColorDayMode | 0 x 93025 |
| MajorSpeedAlertBackgroundColorNightMode | 0 x 93025 |
| MajorSpeedAlertTextColorDayMode | 0xffffff(白色) |
| MajorSpeedAlertTextColorNightMode | 0xffffff(白色) |
您可以為輕微和主要速度警示指定計速器的文字和背景顏色：
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;
接收司機提供的速度資訊
如果您的應用程式需要分享驅動程式速度資訊，您也可以使用 Navigation SDK 提供驅動程式的速度資訊。這對於代僱駕駛服務應用程式來說十分實用，若應用程式操作員希望監控駕駛人過速，提升安全性，這項功能就相當實用。
舉例來說，以下範例會在速度超出速限的特定百分比時分享速度資訊：
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 { ... }