Method IdentifyLayerAsync
IdentifyLayerAsync(Layer, Point, Double, Boolean)
Initiates an identify operation on the specified layer which will return the single visible topmost geolement only.
Declaration
public Task<IdentifyLayerResult> IdentifyLayerAsync(Layer layer, Point screenPoint, double tolerance, bool returnPopupsOnly)
Parameters
Type | Name | Description |
---|---|---|
Layer | layer | The layer in which to identify the geoelements. |
Windows.Foundation.Point | screenPoint | The screen coordinates to identify the geoelements. |
System.Double | tolerance | A radius in device-independent pixels (DIP) that specifies how precise the identify operation should be. |
System.Boolean | returnPopupsOnly |
|
Returns
Type | Description |
---|---|
System.Threading.Tasks.Task<IdentifyLayerResult> | A task that represents the asynchronous identify operation on the specified layer. The value of the TResult parameter contains IdentifyLayerResult |
Remarks
As locations from user gestures are not always accurate to the exact pixel, you can define a tolerance for the identify operation. The tolerance parameter sets the radius of a circle, centered at the specified coordinates, in device-independent pixels (DIP). If the tolerance value is 0, identify performs the test at the specified coordinates. If it is greater than 0, identify tests inside the circle. For touch displays a value of 22 is recommended to cover an average finger tap. The maximum allowed value is 100 DIPs.
The result is returned in a single IdentifyLayerResult instance. If the returnPopupsOnly
parameter is true
only Popups is populated. If the layer does not have popups an error is returned.
If the returnPopupsOnly
parameter is false
, both GeoElements and
Popups are populated, if the layer has popups.
Applies to
Platforms and versions
Target | Versions |
---|---|
.NET Windows | 100.13 - 200.5 |
IdentifyLayerAsync(Layer, Point, Double, Boolean, CancellationToken)
Initiates an identify operation on the specified layer which will return the single visible topmost GeoElement only.
Declaration
public Task<IdentifyLayerResult> IdentifyLayerAsync(Layer layer, Point screenPoint, double tolerance, bool returnPopupsOnly, CancellationToken cancellationToken)
Parameters
Type | Name | Description |
---|---|---|
Layer | layer | The layer on which to run the identify. |
Windows.Foundation.Point | screenPoint | The location at which to run identify in screen coordinates. |
System.Double | tolerance | The width and height in screen coordinates of the square centered on screen coordinate that will be used in the identify. |
System.Boolean | returnPopupsOnly |
|
System.Threading.CancellationToken | cancellationToken | A cancellation token that can be used by other objects or threads to receive notice of cancellation. |
Returns
Type | Description |
---|---|
System.Threading.Tasks.Task<IdentifyLayerResult> | A task that represents the asynchronous identify operation on the specified layer. The value of the TResult parameter contains IdentifyLayerResult |
Remarks
As locations from user gestures are not always accurate to the exact pixel, you can define a tolerance for the identify operation. The tolerance parameter sets the radius of a circle, centered at the specified coordinates, in device-independent pixels (DIP). If the tolerance value is 0, identify performs the test at the specified coordinates. If it is greater than 0, identify tests inside the circle. For touch displays a value of 22 is recommended to cover an average finger tap. The maximum allowed value is 100 DIPs.
The result is returned in a single IdentifyLayerResult instance. If the returnPopupsOnly
parameter is true
only Popups is populated. If the layer does not have popups an error is returned.
If the returnPopupsOnly
parameter is false
, both GeoElements and
Popups are populated, if the layer has popups.
Applies to
Platforms and versions
Target | Versions |
---|---|
.NET Windows | 100.13 - 200.5 |
IdentifyLayerAsync(Layer, Point, Double, Boolean, Int64)
Identifies a limited number of geoelements in the specified layer or sublayer, at the given screen point.
Declaration
public Task<IdentifyLayerResult> IdentifyLayerAsync(Layer layer, Point screenPoint, double tolerance, bool returnPopupsOnly, long maximumResults)
Parameters
Type | Name | Description |
---|---|---|
Layer | layer | The layer in which to identify the geoelements. |
Windows.Foundation.Point | screenPoint | The screen coordinates to identify the geoelements. |
System.Double | tolerance | A radius in device-independent pixels (DIP) that specifies how precise the identify operation should be. |
System.Boolean | returnPopupsOnly |
|
System.Int64 | maximumResults | The maximum number of geoelements and/or popups returned in the IdentifyLayerResult. A value of -1 indicates unlimited results. |
Returns
Type | Description |
---|---|
System.Threading.Tasks.Task<IdentifyLayerResult> | A task that represents the asynchronous identify operation on the specified layer. The value of the TResult parameter contains IdentifyLayerResult |
Remarks
As locations from user gestures are not always accurate to the exact pixel, you can define a tolerance for the identify operation. The tolerance parameter sets the radius of a circle, centered at the specified coordinates, in device-independent pixels (DIP). If the tolerance value is 0, identify performs the test at the specified coordinates. If it is greater than 0, identify tests inside the circle. For touch displays a value of 22 is recommended to cover an average finger tap. The maximum allowed value is 100 DIPs.
The result is returned in a single IdentifyLayerResult instance. If the returnPopupsOnly
parameter is true
only Popups is populated. If the layer does not have popups an error is returned.
If the returnPopupsOnly
parameter is false
, both GeoElements and
Popups are populated, if the layer has popups. GeoElements
and Popups provide the results in a top-to-bottom order.
Applies to
Platforms and versions
Target | Versions |
---|---|
.NET Windows | 100.13 - 200.5 |
IdentifyLayerAsync(Layer, Point, Double, Boolean, Int64, CancellationToken)
Initiates an identify operation on the specified layer.
Declaration
public Task<IdentifyLayerResult> IdentifyLayerAsync(Layer layer, Point screenPoint, double tolerance, bool returnPopupsOnly, long maximumResults, CancellationToken cancellationToken)
Parameters
Type | Name | Description |
---|---|---|
Layer | layer | The layer on which to run the identify. |
Windows.Foundation.Point | screenPoint | The location at which to run identify in screen coordinates. |
System.Double | tolerance | The width and height in screen coordinates of the square centered on screen coordinate that will be used in the identify. |
System.Boolean | returnPopupsOnly |
|
System.Int64 | maximumResults | The maximum size of the result set of GeoElements. |
System.Threading.CancellationToken | cancellationToken | A cancellation token that can be used by other objects or threads to receive notice of cancellation. |
Returns
Type | Description |
---|---|
System.Threading.Tasks.Task<IdentifyLayerResult> | A task that represents the asynchronous identify operation on the specified layer. The value of the TResult parameter contains IdentifyLayerResult |
Remarks
As locations from user gestures are not always accurate to the exact pixel, you can define a tolerance for the identify operation. The tolerance parameter sets the radius of a circle, centered at the specified coordinates, in device-independent pixels (DIP). If the tolerance value is 0, identify performs the test at the specified coordinates. If it is greater than 0, identify tests inside the circle. For touch displays a value of 22 is recommended to cover an average finger tap. The maximum allowed value is 100 DIPs.
The result is returned in a single IdentifyLayerResult instance. If the returnPopupsOnly
parameter is true
only Popups is populated. If the layer does not have popups an error is returned.
If the returnPopupsOnly
parameter is false
, both GeoElements and
Popups are populated, if the layer has popups. GeoElements
and Popups provide the results in a top-to-bottom order.
Applies to
Platforms and versions
Target | Versions |
---|---|
.NET Windows | 100.13 - 200.5 |