create annotations

Question

Hi All

I am working to implement an annotation tool，Click the button to display all annotations.Why do I use this code to create annotations, but when the program runs it shows blank space?Am i missing something？

（c sharp code）

CIMLabelClass labelClass = new CIMLabelClass
{Visibility = true };
 labelClasses.Add(labelClass);
layerDef.LabelClasses = labelClasses.ToArray();
layerDef.LabelVisibility = true;
layer.SetDefinition(layerDef);
mapView.Redraw(true);

Thanks!

rs

rs_gs · Answer

Okay, I tried it. The problem still persists. I will try other methods. Thank you for your reply many times.

GKmieliauskas · Answer

Try to put mapView.Redraw(true); in another QueuedTask.Run. Sometimes separating MCT threads helps.

Or use RedrawAsync method outside QueuedTask.Run  which doesn't need MCT thread.

rs_gs · Answer

I've created several tag classes.After the code is run,  tag classes are generated，but it doesn't show.However, without changing any parameters, manually operate ArcGIS pro, click the Apply button, the label will be displayed.

Thanks.

CIMLabelClass labelClass = new CIMLabelClass

{
Name = $"LabelClass_{value}",
Expression = "$feature.Label", 
ExpressionEngine = LabelExpressionEngine.Arcade, 
Priority = 0,
Visibility = true,
WhereClause = $"Label = '{river}'", 
TextSymbol = SymbolFactory.Instance.ConstructTextSymbol(color, 15, "Arial").MakeSymbolReference(),

};

labelClasses.Add(labelClass);

var layerDef = featureLayer.GetDefinition() as CIMFeatureLayer;
layerDef.LabelClasses = labelClasses.ToArray();
featureLayer.SetDefinition(layerDef);
featureLayer.SetLabelVisibility(true);

mapView.Redraw(true);