本部分介绍了如何使用 JavaScript 车队跟踪库查看车队。这些过程假定您已设置车队跟踪库并加载了地图。如需了解详情，请参阅设置 JavaScript 车队跟踪库。
本文档介绍了您在查看车队时可以执行的以下操作：
开始跟踪车队
如需跟踪车队，您需要实例化车队位置信息提供程序，并为地图视口设置位置限制，如以下部分所述。
实例化车队位置信息提供程序
JavaScript 车队跟踪库包含一个位置信息提供程序，用于从车队引擎提取多辆车辆。
如需实例化它，请按以下步骤操作：
使用您的项目 ID 以及对令牌提取程序的引用。
使用车辆过滤条件查询：车辆过滤条件查询用于控制地图显示哪些车辆。过滤条件会传递给 Fleet Engine。
- 对于按需服务，请使用
vehicleFilter，并查看ListVehiclesRequest.filter - 对于安排的任务，请使用
deliveryVehicleFilter，并查看ListDeliveryVehiclesRequest.filter
- 对于按需服务，请使用
设置车载显示屏的边界区域。使用
locationRestriction可限制在地图上显示车辆的区域。在设置此参数之前，位置信息提供程序处于非活跃状态。您可以在构造函数中或构造函数之后设置位置边界。初始化地图视图。
以下示例展示了如何针对按需和安排的任务场景实例化车队位置信息提供程序。这些示例还展示了如何在构造函数中使用 locationRestriction 使位置信息提供程序处于活动状态。
按需行程
JavaScript
locationProvider =
new google.maps.journeySharing
.FleetEngineFleetLocationProvider({
projectId,
authTokenFetcher,
// Optionally, specify location bounds to
// limit which vehicles are
// retrieved and immediately start tracking.
locationRestriction: {
north: 37.3,
east: -121.8,
south: 37.1,
west: -122,
},
// Optionally, specify a filter to limit
// which vehicles are retrieved.
vehicleFilter:
'attributes.foo = "bar" AND attributes.baz = "qux"',
});
TypeScript
locationProvider =
new google.maps.journeySharing
.FleetEngineFleetLocationProvider({
projectId,
authTokenFetcher,
// Optionally, specify location bounds to
// limit which vehicles are
// retrieved and immediately start tracking.
locationRestriction: {
north: 37.3,
east: -121.8,
south: 37.1,
west: -122,
},
// Optionally, specify a filter to limit
// which vehicles are retrieved.
vehicleFilter:
'attributes.foo = "bar" AND attributes.baz = "qux"',
});
计划任务
JavaScript
locationProvider =
new google.maps.journeySharing
.FleetEngineDeliveryFleetLocationProvider({
projectId,
authTokenFetcher,
// Optionally, specify location bounds to
// limit which delivery vehicles are
// retrieved and immediately make the location provider active.
locationRestriction: {
north: 37.3,
east: -121.8,
south: 37.1,
west: -122,
},
// Optionally, specify a filter to limit
// which delivery vehicles are retrieved.
deliveryVehicleFilter:
'attributes.foo = "bar" AND attributes.baz = "qux"',
});
TypeScript
locationProvider =
new google.maps.journeySharing
.FleetEngineDeliveryFleetLocationProvider({
projectId,
authTokenFetcher,
// Optionally, specify location bounds to
// limit which delivery vehicles are
// retrieved and immediately make the location provider active.
locationRestriction: {
north: 37.3,
east: -121.8,
south: 37.1,
west: -122,
},
// Optionally, specify a filter to limit
// which delivery vehicles are retrieved.
deliveryVehicleFilter:
'attributes.foo = "bar" AND attributes.baz = "qux"',
});
如需在构造函数后设置 locationRestriction，请在代码的后面添加 locationProvider.locationRestriction，如以下 JavaScript 示例所示。
// You can choose to not set locationRestriction in the constructor.
// In this case, the location provider *DOES NOT START* after this line, because
// no locationRestriction is set.
locationProvider = new google.maps.journeySharing.DeliveryFleetLocationProvider({
... // not setting locationRestriction here
});
// You can then set the locationRestriction *after* the constructor.
// After this line, the location provider is active.
locationProvider.locationRestriction = {
north: 1,
east: 2,
south: 0,
west: 1,
};
使用地图视口设置位置限制
您还可以设置 locationRestriction 边界，使其与地图视图中当前可见的区域相匹配。
按需行程
JavaScript
google.maps.event.addListenerOnce(
mapView.map, 'bounds_changed', () => {
const bounds = mapView.map.getBounds();
if (bounds) {
// If you did not specify a location restriction in the
// location provider constructor, you may do so here.
// Location tracking will start as soon as this is set.
locationProvider.locationRestriction = bounds;
}
});
TypeScript
google.maps.event.addListenerOnce(
mapView.map, 'bounds_changed', () => {
const bounds = mapView.map.getBounds();
if (bounds) {
// If you did not specify a location restriction in the
// location provider constructor, you may do so here.
// Location tracking will start as soon as this is set.
locationProvider.locationRestriction = bounds;
}
});
计划任务
JavaScript
google.maps.event.addListenerOnce(
mapView.map, 'bounds_changed', () => {
const bounds = mapView.map.getBounds();
if (bounds) {
// If you did not specify a location restriction in the
// location provider constructor, you may do so here.
// Location provider will start as soon as this is set.
locationProvider.locationRestriction = bounds;
}
});
TypeScript
google.maps.event.addListenerOnce(
mapView.map, 'bounds_changed', () => {
const bounds = mapView.map.getBounds();
if (bounds) {
// If you did not specify a location restriction in the
// location provider constructor, you may do so here.
// Location provider will start as soon as this is set.
locationProvider.locationRestriction = bounds;
}
});
初始化地图视图
构建位置信息提供程序后，请按照跟踪单个车辆时的方式初始化地图视图。
加载 JavaScript 历程共享库后，初始化地图视图并将其添加到 HTML 页面。您的网页应包含一个用于容纳地图视图的 <div> 元素。在以下示例中，<div> 元素名为 map_canvas。=
按需行程
JavaScript
const mapView = new
google.maps.journeySharing.JourneySharingMapView({
element: document.getElementById('map_canvas'),
locationProviders: [locationProvider],
});
// If you did not specify a vehicle ID in the
// location provider constructor, you may do so here.
// Location tracking will start as soon as this is set.
locationProvider.vehicleId
= 'your-vehicle-id';
// Give the map an initial viewport to allow it to
// initialize; otherwise the 'ready' event above may
// not fire. The user also has access to the mapView
// object to customize as they want.
mapView.map.setCenter('Times Square, New York, NY');
mapView.map.setZoom(14);
TypeScript
const mapView = new
google.maps.journeySharing.JourneySharingMapView({
element: document.getElementById('map_canvas'),
locationProviders: [locationProvider],
});
// If you did not specify a vehicle ID in the
// location provider constructor, you may do so here.
// Location tracking will start as soon as this is set.
locationProvider.VehicleId
= 'your-vehicle-id';
// Give the map an initial viewport to allow it to
// initialize; otherwise the 'ready' event above may
// not fire. The user also has access to the mapView
// object to customize as they want.
mapView.map.setCenter('Times Square, New York, NY');
mapView.map.setZoom(14);
计划任务
JavaScript
const mapView = new
google.maps.journeySharing.JourneySharingMapView({
element: document.getElementById('map_canvas'),
locationProviders: [locationProvider],
});
// If you did not specify a delivery vehicle ID in the
// location provider constructor, you may do so here.
// Location tracking will start as soon as this is set.
locationProvider.deliveryVehicleId
= 'your-delivery-vehicle-id';
// Give the map an initial viewport to allow it to
// initialize; otherwise the 'ready' event above may
// not fire. The user also has access to the mapView
// object to customize as they want.
mapView.map.setCenter('Times Square, New York, NY');
mapView.map.setZoom(14);
TypeScript
const mapView = new
google.maps.journeySharing.JourneySharingMapView({
element: document.getElementById('map_canvas'),
locationProviders: [locationProvider],
});
// If you did not specify a delivery vehicle ID in the
// location provider constructor, you may do so here.
// Location tracking will start as soon as this is set.
locationProvider.deliveryVehicleId
= 'your-delivery-vehicle-id';
// Give the map an initial viewport to allow it to
// initialize; otherwise the 'ready' event above may
// not fire. The user also has access to the mapView
// object to customize as they want.
mapView.map.setCenter('Times Square, New York, NY');
mapView.map.setZoom(14);
监听事件和处理错误
开始跟踪车队后，您需要监听事件变化并处理出现的任何错误，如以下部分所述。
监听更改事件
您可以使用位置信息提供程序从车辆对象检索有关车队的元信息。对元信息所做的更改会触发更新事件。元信息包括导航状态、剩余距离和自定义属性等车辆属性。
如需了解详情，请参阅以下内容：
以下示例展示了如何监听这些更改事件。
按需行程
JavaScript
locationProvider.addListener('update', e => {
// e.vehicles contains data that may be
// useful to the rest of the UI.
for (vehicle of e.vehicles) {
console.log(vehicle.navigationStatus);
}
});
TypeScript
locationProvider.addListener('update',
(e: google.maps.journeySharing.FleetEngineFleetLocationProviderUpdateEvent) => {
// e.vehicles contains data that may be
// useful to the rest of the UI.
if (e.vehicles) {
for (vehicle of e.vehicles) {
console.log(vehicle.navigationStatus);
}
}
});
计划任务
JavaScript
locationProvider.addListener('update', e => {
// e.deliveryVehicles contains data that may be
// useful to the rest of the UI.
if (e.deliveryVehicles) {
for (vehicle of e.deliveryVehicles) {
console.log(vehicle.remainingDistanceMeters);
}
}
});
TypeScript
locationProvider.addListener('update',
(e: google.maps.journeySharing.FleetEngineDeliveryFleetLocationProviderUpdateEvent) => {
// e.deliveryVehicles contains data that may be
// useful to the rest of the UI.
if (e.deliveryVehicles) {
for (vehicle of e.deliveryVehicles) {
console.log(vehicle.remainingDistanceMeters);
}
}
});
监听错误
您还需要监听并处理跟踪车辆期间发生的错误。由于请求车辆信息而异步产生的错误会触发错误事件。
以下示例展示了如何监听这些事件，以便处理错误。
JavaScript
locationProvider.addListener('error', e => {
// e.error is the error that triggered the event.
console.error(e.error);
});
TypeScript
locationProvider.addListener('error', (e: google.maps.ErrorEvent) => {
// e.error is the error that triggered the event.
console.error(e.error);
});
停止跟踪车队
如需停止跟踪车队，您可以将位置信息提供程序的边界设置为 null，然后按照以下部分所述从地图视图中移除位置信息提供程序。
将位置信息提供程序边界设置为 null
如需停止位置信息提供程序跟踪车队，请将位置信息提供程序的边界设置为 null。
按需行程
JavaScript
locationProvider.locationRestriction = null;
TypeScript
locationProvider.locationRestriction = null;
计划任务
JavaScript
locationProvider.locationRestriction = null;
TypeScript
locationProvider.locationRestriction = null;
从地图视图中移除位置信息提供程序
以下示例展示了如何从地图视图中移除位置信息提供程序。
JavaScript
mapView.removeLocationProvider(locationProvider);
TypeScript
mapView.removeLocationProvider(locationProvider);
查看配送车队时跟踪配送车辆
如果您将 Mobility 服务用于安排的任务，则可以在同一地图视图中查看车队，并显示特定配送车辆的路线和即将执行的任务。为此，请实例化一个配送车队位置信息提供程序和一个配送车辆位置信息提供程序，并将它们都添加到地图视图。实例化后，配送车队位置信息提供程序会开始在地图上显示配送车辆。以下示例展示了如何实例化这两种位置信息提供程序：
JavaScript
deliveryFleetLocationProvider =
new google.maps.journeySharing
.FleetEngineDeliveryFleetLocationProvider({
projectId,
authTokenFetcher,
// Optionally, specify location bounds to
// limit which delivery vehicles are
// retrieved and immediately start tracking.
locationRestriction: {
north: 37.3,
east: -121.8,
south: 37.1,
west: -122,
},
// Optionally, specify a filter to limit
// which delivery vehicles are retrieved.
deliveryVehicleFilter:
'attributes.foo = "bar" AND attributes.baz = "qux"',
});
deliveryVehicleLocationProvider =
new google.maps.journeySharing
.FleetEngineDeliveryVehicleLocationProvider({
projectId,
authTokenFetcher
});
const mapView = new
google.maps.journeySharing.JourneySharingMapView({
element: document.getElementById('map_canvas'),
locationProviders: [
deliveryFleetLocationProvider,
deliveryVehicleLocationProvider,
],
// Any other options
});
TypeScript
deliveryFleetLocationProvider =
new google.maps.journeySharing
.FleetEngineDeliveryFleetLocationProvider({
projectId,
authTokenFetcher,
// Optionally, specify location bounds to
// limit which delivery vehicles are
// retrieved and immediately start tracking.
locationRestriction: {
north: 37.3,
east: -121.8,
south: 37.1,
west: -122,
},
// Optionally, specify a filter to limit
// which delivery vehicles are retrieved.
deliveryVehicleFilter:
'attributes.foo = "bar" AND attributes.baz = "qux"',
});
deliveryVehicleLocationProvider =
new google.maps.journeySharing
.FleetEngineDeliveryVehicleLocationProvider({
projectId,
authTokenFetcher
});
const mapView = new
google.maps.journeySharing.JourneySharingMapView({
element: document.getElementById('map_canvas'),
locationProviders: [
deliveryFleetLocationProvider,
deliveryVehicleLocationProvider,
],
// Any other options
});
使用标记自定义功能跟踪配送车辆
若要让配送车辆位置信息提供程序在您点击配送车辆的车队标记时跟踪配送车辆，请按以下步骤操作：
自定义标记并添加点击操作。
隐藏标记以防止重复标记。
以下部分提供了这些步骤的示例。
自定义标记并添加点击操作
JavaScript
// Specify the customization function either separately, or as a field in
// the options for the delivery fleet location provider constructor.
deliveryFleetLocationProvider.deliveryVehicleMarkerCustomization =
(params) => {
if (params.isNew) {
params.marker.addListener('click', () => {
// params.vehicle.name follows the format
// "providers/{provider}/deliveryVehicles/{vehicleId}".
// Only the vehicleId portion is used for the delivery vehicle
// location provider.
deliveryVehicleLocationProvider.deliveryVehicleId =
params.vehicle.name.split('/').pop();
});
}
};
TypeScript
// Specify the customization function either separately, or as a field in
// the options for the delivery fleet location provider constructor.
deliveryFleetLocationProvider.deliveryVehicleMarkerCustomization =
(params: google.maps.journeySharing.DeliveryVehicleMarkerCustomizationFunctionParams) => {
if (params.isNew) {
params.marker.addListener('click', () => {
// params.vehicle.name follows the format
// "providers/{provider}/deliveryVehicles/{vehicleId}".
// Only the vehicleId portion is used for the delivery vehicle
// location provider.
deliveryVehicleLocationProvider.deliveryVehicleId =
params.vehicle.name.split('/').pop();
});
}
};
隐藏标记以防止重复标记
从配送车辆位置信息提供程序中隐藏标记，以防止为同一车辆呈现两个标记：
JavaScript
// Specify the customization function either separately, or as a field in
// the options for the delivery vehicle location provider constructor.
deliveryVehicleLocationProvider.deliveryVehicleMarkerCustomization =
(params) => {
if (params.isNew) {
params.marker.setVisible(false);
}
};
TypeScript
// Specify the customization function either separately, or as a field in
// the options for the delivery vehicle location provider constructor.
deliveryVehicleLocationProvider.deliveryVehicleMarkerCustomization =
(params: deliveryVehicleMarkerCustomizationFunctionParams) => {
if (params.isNew) {
params.marker.setVisible(false);
}
};