layout: default title: MapComponent parent: Core Classes —
dymaptic.GeoBlazor.Core
dymaptic.GeoBlazor.Core.Components
MapComponent Class
The abstract base Razor Component class that all GeoBlazor components derive from.
public abstract class MapComponent : Microsoft.AspNetCore.Components.ComponentBase,
System.IAsyncDisposable
Inheritance System.Object 🡒 Microsoft.AspNetCore.Components.ComponentBase 🡒 MapComponent
Derived
↳ ActionBase
↳ Basemap
↳ BasemapStyle
↳ Constraints
↳ Geometry
↳ SpatialReference
↳ ColorStop
↳ DynamicDataSource
↳ DynamicLayer
↳ DynamicLayerField
↳ Field
↳ FieldsIndex
↳ LabelExpressionInfo
↳ Layer
↳ LayerFloorInfo
↳ LayerObject
↳ LegendOptions
↳ MultidimensionalSubset
↳ OpacityStop
↳ OrderedLayerOrderBy
↳ SizeStop
↳ Sublayer
↳ TileInfo
↳ VisualVariable
↳ LOD
↳ Map
↳ ChartMediaInfoValue
↳ ChartMediaInfoValueSeries
↳ ExpressionInfo
↳ FieldInfo
↳ FieldInfoFormat
↳ ImageMediaInfoValue
↳ MediaInfo
↳ PopupContent
↳ PopupTemplate
↳ RelatedRecordsInfoFieldOrder
↳ Portal
↳ PortalBasemapsSource
↳ PortalItem
↳ ColorRamp
↳ DefaultSymbol
↳ RasterStretchRenderer
↳ UniqueValueRendererLegendOptions
↳ MapFont
↳ Symbol
↳ MapView
↳ Viewpoint
↳ BasemapLayerListWidgetVisibleElements
↳ Bookmark
↳ CodedValue<T>
↳ Domain
↳ FormElement
↳ FormInput
↳ FormTemplate
↳ LayerInfo
↳ LegendStyle
↳ PopupDockOptions
↳ PopupVisibleElements
↳ SliderTickConfig
↳ SliderVisibleElements
↳ Widget
↳ HighlightOptions
↳ LayerSearchSourceFilter
↳ LocatorSearchSourceFilter
↳ SearchSource
Implements System.IAsyncDisposable
Fields
MapComponent.AllowRender Field
Whether to allow the component to render on the next cycle.
public bool AllowRender;
Field Value
Properties
MapComponent.ChildContent Property
ChildContent defines the ability to add other components within this component in the razor syntax.
public Microsoft.AspNetCore.Components.RenderFragment? ChildContent { get; set; }
Property Value
Microsoft.AspNetCore.Components.RenderFragment
MapComponent.Id Property
A unique identifier, used to track components across .NET and JavaScript.
public System.Guid Id { get; set; }
Property Value
MapComponent.JsModule Property
The reference to arcGisJsInterop.ts from .NET
public Microsoft.JSInterop.IJSObjectReference? JsModule { get; set; }
Property Value
Microsoft.JSInterop.IJSObjectReference
MapComponent.JsRuntime Property
Represents an instance of a JavaScript runtime to which calls may be dispatched.
public Microsoft.JSInterop.IJSRuntime JsRuntime { get; set; }
Property Value
Microsoft.JSInterop.IJSRuntime
MapComponent.MapRendered Property
A boolean flag that indicates that the current MapView has finished rendering.
To listen for a map rendering event, use OnViewRendered.
public bool MapRendered { get; set; }
Property Value
MapComponent.Parent Property
The parent MapComponent of this component.
public dymaptic.GeoBlazor.Core.Components.MapComponent? Parent { get; set; }
Property Value
MapComponent.ProJsModule Property
Optional JsModule for GeoBlazor Pro
public Microsoft.JSInterop.IJSObjectReference? ProJsModule { get; set; }
Property Value
Microsoft.JSInterop.IJSObjectReference
MapComponent.ProProperties Property
Extension properties for GeoBlazor Pro
public System.Collections.Generic.Dictionary<string,object?>? ProProperties { get; set; }
Property Value
System.Collections.Generic.Dictionary<System.String,System.Object>
MapComponent.View Property
The parent MapView of the current component.
public dymaptic.GeoBlazor.Core.Components.Views.MapView? View { get; set; }
Property Value
MapComponent.Visible Property
Indicates the visibility of the component. Default value: true.
public System.Nullable<bool> Visible { get; set; }
Property Value
System.Nullable<System.Boolean>
Methods
MapComponent.Add(MapComponent) Method
Add a child component programmatically. Calls RegisterChildComponent(MapComponent) internally.
public System.Threading.Tasks.Task Add(dymaptic.GeoBlazor.Core.Components.MapComponent child);
Parameters
child MapComponent
The child component to add
Returns
MapComponent.AddReactiveListener(string, Action, bool) Method
Tracks any properties accessed in the
listenExpression
``` and calls the callback when any of them change.
```csharp
public System.Threading.Tasks.Task AddReactiveListener<T>(string eventName, System.Action<T> handler, bool once=false);
Type parameters
T
The type of return value to expect in the handler.
Parameters
eventName System.String
The name of the event to add a listener for.
handler System.Action<T>
The function to call when there are changes.
once System.Boolean
Whether to fire the callback only once. Defaults to false.
Returns
MapComponent.AddReactiveListener(string, Func<T,Task>, bool) Method
Tracks any properties accessed in the
listenExpression
``` and calls the callback when any of them change.
```csharp
public System.Threading.Tasks.Task AddReactiveListener<T>(string eventName, System.Func<T,System.Threading.Tasks.Task> handler, bool once=false);
Type parameters
T
The type of return value to expect in the handler.
Parameters
eventName System.String
The name of the event to add a listener for.
handler System.Func<T,System.Threading.Tasks.Task>
The function to call when the event triggers.
once System.Boolean
Whether to fire the callback only once. Defaults to false.
Returns
MapComponent.AddReactiveWaiter(string, Action, string, bool, bool) Method
Tracks a value in the
waitExpression
``` and calls the callback when it becomes
<a target="_blank" href="https://developer.mozilla.org/en-US/docs/Glossary/Truthy">truthy</a>.
```csharp
public System.Threading.Tasks.Task AddReactiveWaiter(string waitExpression, System.Action handler, string? targetName=null, bool once=false, bool initial=false);
Parameters
waitExpression System.String
Expression used to get the current value. All accessed properties will be tracked.
handler System.Action
The function to call when the value is truthy.
targetName System.String
The name of the target you are referencing in the
waitExpression
```. For example, if the expression is
"layer?.refresh", then the targetName should be "layer". The type of the target should also match the class on
which this method was called.
<a name='dymaptic.GeoBlazor.Core.Components.MapComponent.AddReactiveWaiter(string,System.Action,string,bool,bool).once'></a>
`once` [System.Boolean](https://docs.microsoft.com/en-us/dotnet/api/System.Boolean 'System.Boolean')
Whether to fire the callback only once.
<a name='dymaptic.GeoBlazor.Core.Components.MapComponent.AddReactiveWaiter(string,System.Action,string,bool,bool).initial'></a>
`initial` [System.Boolean](https://docs.microsoft.com/en-us/dotnet/api/System.Boolean 'System.Boolean')
Whether to fire the callback immediately after initialization, if the necessary conditions are met.
#### Returns
[System.Threading.Tasks.Task](https://docs.microsoft.com/en-us/dotnet/api/System.Threading.Tasks.Task 'System.Threading.Tasks.Task')
#### Exceptions
[UnMatchedTargetNameException](dymaptic.GeoBlazor.Core.Exceptions.UnMatchedTargetNameException.html 'dymaptic.GeoBlazor.Core.Exceptions.UnMatchedTargetNameException')
This exception is thrown when a watchExpression's target object name doesn't match the targetName parameter.
### Remarks
For adding waiters to types other than [MapView](dymaptic.GeoBlazor.Core.Components.Views.MapView.html 'dymaptic.GeoBlazor.Core.Components.Views.MapView') and [SceneView](dymaptic.GeoBlazor.Core.Components.Views.SceneView.html 'dymaptic.GeoBlazor.Core.Components.Views.SceneView'), the default
```csharp
targetName
``` should not be relied upon. Make sure it matches the variable in your
```csharp
waitExpression
MapComponent.AddReactiveWaiter(string, Func, string, bool, bool) Method
Tracks a value in the
waitExpression
``` and calls the callback when it becomes
<a target="_blank" href="https://developer.mozilla.org/en-US/docs/Glossary/Truthy">truthy</a>.
```csharp
public System.Threading.Tasks.Task AddReactiveWaiter(string waitExpression, System.Func<System.Threading.Tasks.Task> handler, string? targetName=null, bool once=false, bool initial=false);
Parameters
waitExpression System.String
Expression used to get the current value. All accessed properties will be tracked.
handler System.Func<System.Threading.Tasks.Task>
The function to call when the value is truthy.
targetName System.String
The name of the target you are referencing in the
waitExpression
```. For example, if the expression is
"layer?.refresh", then the targetName should be "layer". The type of the target should also match the class on
which this method was called.
<a name='dymaptic.GeoBlazor.Core.Components.MapComponent.AddReactiveWaiter(string,System.Func_System.Threading.Tasks.Task_,string,bool,bool).once'></a>
`once` [System.Boolean](https://docs.microsoft.com/en-us/dotnet/api/System.Boolean 'System.Boolean')
Whether to fire the callback only once.
<a name='dymaptic.GeoBlazor.Core.Components.MapComponent.AddReactiveWaiter(string,System.Func_System.Threading.Tasks.Task_,string,bool,bool).initial'></a>
`initial` [System.Boolean](https://docs.microsoft.com/en-us/dotnet/api/System.Boolean 'System.Boolean')
Whether to fire the callback immediately after initialization, if the necessary conditions are met.
#### Returns
[System.Threading.Tasks.Task](https://docs.microsoft.com/en-us/dotnet/api/System.Threading.Tasks.Task 'System.Threading.Tasks.Task')
#### Exceptions
[UnMatchedTargetNameException](dymaptic.GeoBlazor.Core.Exceptions.UnMatchedTargetNameException.html 'dymaptic.GeoBlazor.Core.Exceptions.UnMatchedTargetNameException')
This exception is thrown when a watchExpression's target object name doesn't match the targetName parameter.
### Remarks
For adding waiters to types other than [MapView](dymaptic.GeoBlazor.Core.Components.Views.MapView.html 'dymaptic.GeoBlazor.Core.Components.Views.MapView') and [SceneView](dymaptic.GeoBlazor.Core.Components.Views.SceneView.html 'dymaptic.GeoBlazor.Core.Components.Views.SceneView'), the default
```csharp
targetName
``` should not be relied upon. Make sure it matches the variable in your
```csharp
waitExpression
MapComponent.AddReactiveWatcher(string, Action, string, bool, bool) Method
Tracks any properties accessed in the
watchExpression
``` and calls the callback when any of them change.
```csharp
public System.Threading.Tasks.Task AddReactiveWatcher<T>(string watchExpression, System.Action<T> handler, string? targetName=null, bool once=false, bool initial=false);
Type parameters
T
The type of return value to expect in the handler.
Parameters
watchExpression System.String
Expression used to get the current value. All accessed properties will be tracked.
handler System.Action<T>
The function to call when there are changes.
targetName System.String
The name of the target you are referencing in the
watchExpression
```. For example, if the expression is
"layer?.refresh", then the targetName should be "layer". The type of the target should also match the class on
which this method was called.
<a name='dymaptic.GeoBlazor.Core.Components.MapComponent.AddReactiveWatcher_T_(string,System.Action_T_,string,bool,bool).once'></a>
`once` [System.Boolean](https://docs.microsoft.com/en-us/dotnet/api/System.Boolean 'System.Boolean')
Whether to fire the callback only once.
<a name='dymaptic.GeoBlazor.Core.Components.MapComponent.AddReactiveWatcher_T_(string,System.Action_T_,string,bool,bool).initial'></a>
`initial` [System.Boolean](https://docs.microsoft.com/en-us/dotnet/api/System.Boolean 'System.Boolean')
Whether to fire the callback immediately after initialization, if the necessary conditions are met.
#### Returns
[System.Threading.Tasks.Task](https://docs.microsoft.com/en-us/dotnet/api/System.Threading.Tasks.Task 'System.Threading.Tasks.Task')
#### Exceptions
[UnMatchedTargetNameException](dymaptic.GeoBlazor.Core.Exceptions.UnMatchedTargetNameException.html 'dymaptic.GeoBlazor.Core.Exceptions.UnMatchedTargetNameException')
This exception is thrown when a watchExpression's target object name doesn't match the targetName parameter.
### Remarks
For adding watchers to types other than [MapView](dymaptic.GeoBlazor.Core.Components.Views.MapView.html 'dymaptic.GeoBlazor.Core.Components.Views.MapView') and [SceneView](dymaptic.GeoBlazor.Core.Components.Views.SceneView.html 'dymaptic.GeoBlazor.Core.Components.Views.SceneView'), the default
```csharp
targetName
``` should not be relied upon. Make sure it matches the variable in your
```csharp
watchExpression
MapComponent.AddReactiveWatcher(string, Func<T,Task>, string, bool, bool) Method
Tracks any properties accessed in the
watchExpression
``` and calls the callback when any of them change.
```csharp
public System.Threading.Tasks.Task AddReactiveWatcher<T>(string watchExpression, System.Func<T,System.Threading.Tasks.Task> handler, string? targetName=null, bool once=false, bool initial=false);
Type parameters
T
The type of return value to expect in the handler.
Parameters
watchExpression System.String
Expression used to get the current value. All accessed properties will be tracked.
handler System.Func<T,System.Threading.Tasks.Task>
The function to call when there are changes.
targetName System.String
The name of the target you are referencing in the
watchExpression
```. For example, if the expression is
"layer?.refresh", then the targetName should be "layer". The type of the target should also match the class on
which this method was called.
<a name='dymaptic.GeoBlazor.Core.Components.MapComponent.AddReactiveWatcher_T_(string,System.Func_T,System.Threading.Tasks.Task_,string,bool,bool).once'></a>
`once` [System.Boolean](https://docs.microsoft.com/en-us/dotnet/api/System.Boolean 'System.Boolean')
Whether to fire the callback only once.
<a name='dymaptic.GeoBlazor.Core.Components.MapComponent.AddReactiveWatcher_T_(string,System.Func_T,System.Threading.Tasks.Task_,string,bool,bool).initial'></a>
`initial` [System.Boolean](https://docs.microsoft.com/en-us/dotnet/api/System.Boolean 'System.Boolean')
Whether to fire the callback immediately after initialization, if the necessary conditions are met.
#### Returns
[System.Threading.Tasks.Task](https://docs.microsoft.com/en-us/dotnet/api/System.Threading.Tasks.Task 'System.Threading.Tasks.Task')
#### Exceptions
[UnMatchedTargetNameException](dymaptic.GeoBlazor.Core.Exceptions.UnMatchedTargetNameException.html 'dymaptic.GeoBlazor.Core.Exceptions.UnMatchedTargetNameException')
This exception is thrown when a watchExpression's target object name doesn't match the targetName parameter.
### Remarks
For adding watchers to types other than [MapView](dymaptic.GeoBlazor.Core.Components.Views.MapView.html 'dymaptic.GeoBlazor.Core.Components.Views.MapView') and [SceneView](dymaptic.GeoBlazor.Core.Components.Views.SceneView.html 'dymaptic.GeoBlazor.Core.Components.Views.SceneView'), the default
```csharp
targetName
``` should not be relied upon. Make sure it matches the variable in your
```csharp
watchExpression
MapComponent.AwaitReactiveSingleWatchUpdate(string, string, CancellationToken) Method
Tracks any properties being evaluated by the getValue function. When getValue changes, it returns a Task containing
the value. This method only tracks a single change.
public System.Threading.Tasks.Task<T> AwaitReactiveSingleWatchUpdate<T>(string watchExpression, string? targetName=null, System.Threading.CancellationToken token=default(System.Threading.CancellationToken));
Type parameters
T
The expected return type.
Parameters
watchExpression System.String
The expression to be tracked.
targetName System.String
The name of the target you are referencing in the
waitExpression
```. For example, if the expression is
"layer?.refresh", then the targetName should be "layer". The type of the target should also match the class on
which this method was called.
<a name='dymaptic.GeoBlazor.Core.Components.MapComponent.AwaitReactiveSingleWatchUpdate_T_(string,string,System.Threading.CancellationToken).token'></a>
`token` [System.Threading.CancellationToken](https://docs.microsoft.com/en-us/dotnet/api/System.Threading.CancellationToken 'System.Threading.CancellationToken')
Optional Cancellation Token to abort a listener.
#### Returns
[System.Threading.Tasks.Task<](https://docs.microsoft.com/en-us/dotnet/api/System.Threading.Tasks.Task-1 'System.Threading.Tasks.Task`1')[T](dymaptic.GeoBlazor.Core.Components.MapComponent.html#dymaptic.GeoBlazor.Core.Components.MapComponent.AwaitReactiveSingleWatchUpdate_T_(string,string,System.Threading.CancellationToken).T 'dymaptic.GeoBlazor.Core.Components.MapComponent.AwaitReactiveSingleWatchUpdate<T>(string, string, System.Threading.CancellationToken).T')[>](https://docs.microsoft.com/en-us/dotnet/api/System.Threading.Tasks.Task-1 'System.Threading.Tasks.Task`1')
Returns the value from the evaluated property when it changes.
#### Exceptions
[UnMatchedTargetNameException](dymaptic.GeoBlazor.Core.Exceptions.UnMatchedTargetNameException.html 'dymaptic.GeoBlazor.Core.Exceptions.UnMatchedTargetNameException')
This exception is thrown when a watchExpression's target object name doesn't match the targetName parameter.
<a name='dymaptic.GeoBlazor.Core.Components.MapComponent.DisposeAsync()'></a>
## MapComponent.DisposeAsync() Method
Implements the `IAsyncDisposable` pattern.
```csharp
public virtual System.Threading.Tasks.ValueTask DisposeAsync();
Implements DisposeAsync()
Returns
System.Threading.Tasks.ValueTask
MapComponent.OnReactiveListenerTriggered(string, Nullable) Method
JS-Invokable method that is triggered by the reactiveUtils ‘on’ listeners. This method will dynamically trigger
handlers passed to AddReactiveListener<T>(string, Func<T,Task>, bool)
public void OnReactiveListenerTriggered(string eventName, System.Nullable<System.Text.Json.JsonElement> value);
Parameters
eventName System.String
The tracked event that was triggered.
value System.Nullable<System.Text.Json.JsonElement>
The return value of the watcher callback.
MapComponent.OnReactiveWaiterTrue(string) Method
JS-Invokable method that is triggered by the reactiveUtils waiters. This method will dynamically trigger handlers
passed to AddReactiveWaiter(string, Func<Task>, string, bool, bool)
public void OnReactiveWaiterTrue(string waitExpression);
Parameters
waitExpression System.String
The tracked expression that was triggered.
MapComponent.OnReactiveWatcherUpdate(string, Nullable) Method
JS-Invokable method that is triggered by the reactiveUtils watchers. This method will dynamically trigger handlers
passed to AddReactiveWatcher<T>(string, Func<T,Task>, string, bool, bool)
public void OnReactiveWatcherUpdate(string watchExpression, System.Nullable<System.Text.Json.JsonElement> value);
Parameters
watchExpression System.String
The tracked expression that was triggered.
value System.Nullable<System.Text.Json.JsonElement>
The return value of the watcher callback.
MapComponent.Refresh() Method
Provides a way to externally call StateHasChanged on the component.
public virtual void Refresh();
MapComponent.RegisterChildComponent(MapComponent) Method
Called from dymaptic.GeoBlazor.Core.Components.MapComponent.OnInitializedAsync to “Register” the current component with it’s parent.
public virtual System.Threading.Tasks.Task RegisterChildComponent(dymaptic.GeoBlazor.Core.Components.MapComponent child);
Parameters
child MapComponent
The calling, child component to register
Returns
Exceptions
InvalidChildElementException
Throws if the current child is not a valid sub-component to the parent.
Remarks
This method is an implementation detail and should not be called directly by consumers. In future versions, this may be changed to an internal method. If you see no other way to register a child component, please open an issue on GitHub.
MapComponent.RemoveReactiveListener(string) Method
Removes the tracker on a particular expression.
public System.Threading.Tasks.Task RemoveReactiveListener(string eventName);
Parameters
eventName System.String
The expression to stop tracking.
Returns
MapComponent.RemoveReactiveWaiter(string) Method
Removes the tracker on a particular expression.
public System.Threading.Tasks.Task RemoveReactiveWaiter(string waitExpression);
Parameters
waitExpression System.String
The expression to stop tracking.
Returns
MapComponent.RemoveReactiveWatcher(string) Method
Removes the tracker on a particular expression.
public System.Threading.Tasks.Task RemoveReactiveWatcher(string watchExpression);
Parameters
watchExpression System.String
The expression to stop tracking.
Returns
MapComponent.SetParametersAsync(ParameterView) Method
Sets parameters supplied by the component’s parent in the render tree.
public override System.Threading.Tasks.Task SetParametersAsync(Microsoft.AspNetCore.Components.ParameterView parameters);
Parameters
parameters Microsoft.AspNetCore.Components.ParameterView
The parameters.
Implements SetParametersAsync(ParameterView)
Returns
System.Threading.Tasks.Task
A System.Threading.Tasks.Task that completes when the component has finished updating and rendering itself.
Remarks
Parameters are passed when Microsoft.AspNetCore.Components.ComponentBase.SetParametersAsync(Microsoft.AspNetCore.Components.ParameterView) is called. It is not required that
the caller supply a parameter value for all of the parameters that are logically understood by the component.
The default implementation of Microsoft.AspNetCore.Components.ComponentBase.SetParametersAsync(Microsoft.AspNetCore.Components.ParameterView) will set the value of each property
decorated with Microsoft.AspNetCore.Components.ParameterAttribute or Microsoft.AspNetCore.Components.CascadingParameterAttribute that has
a corresponding value in the Microsoft.AspNetCore.Components.ParameterView. Parameters that do not have a corresponding value
will be unchanged.
MapComponent.SetVisibility(bool) Method
Toggles the visibility of the component.
public System.Threading.Tasks.Task SetVisibility(bool visible);
Parameters
visible System.Boolean
The new value to set for visibility of the component.
Returns
MapComponent.UnregisterChildComponent(MapComponent) Method
Undoes the “Registration” of a child with its parent.
public virtual System.Threading.Tasks.Task UnregisterChildComponent(dymaptic.GeoBlazor.Core.Components.MapComponent child);
Parameters
child MapComponent
The child to unregister
Returns
Remarks
This method is an implementation detail and should not be called directly by consumers. In future versions, this may be changed to an internal method.