topic Re: Programatically PanTo / ZoomTo and then Flash features in ArcObjects SDK Questions

Programatically PanTo / ZoomTo and then Flash features

Anonymous User — Sat, 11 Dec 2021 09:15:32 GMT

Hi!

I am trying to programatically pan to a feature and then flash the feature's geometry. For the "Pan To"-function I'm using the following code:

private IFeature m_feature;

public override void OnClick()
        {
            if (m_feature == null) return;

            IMxDocument pMxDoc = m_application.Document as IMxDocument;
            IActiveView activeView = pMxDoc.ActiveView;

            double midX = (m_feature.Extent.XMax + m_feature.Extent.XMin) / 2;
            double midY = (m_feature.Extent.YMax + m_feature.Extent.YMin) / 2;
            IPoint pPoint = new PointClass();
            pPoint.SpatialReference = m_feature.Extent.SpatialReference;
            pPoint.PutCoords(midX, midY);
            pPoint.Project(activeView.Extent.SpatialReference);

            IEnvelope pCurrentEnvelope = activeView.Extent;
            pCurrentEnvelope.CenterAt(pPoint);

            activeView.Extent = pCurrentEnvelope;
            activeView.Refresh();
        }

After panning I'm calling FlashGeometry (taken from here: http://help.arcgis.com/en/sdk/10.0/arcobjects_net/componenthelp/index.html#//004900000075000000).

When executing the code in ArcMap the Flash is always done before the Pan and i don't know why:

A moment before the Pan is visible on screen the feature is flashed in the correct position, but the panning seems not to be finished although I'm calling the methods in the right order.

Please help me :confused:

Regards,
Christian

P.S.: I'm using ArcGIS Desktop 9.3.1. I'm not using ArcGIS Engine.

Solution

Anonymous User — Sat, 11 Dec 2021 09:15:34 GMT

I found a solution myself after searching the old forums 😮

Use IActiveView.Display.UpdateWindow before you run the flash command, this ensures the map has been fully redraw before any other code is executed:

public override void OnClick()
        {
            if (m_feature == null) return;

            IMxDocument pMxDoc = m_application.Document as IMxDocument;
            IActiveView activeView = pMxDoc.ActiveView;

            double midX = (m_feature.Extent.XMax + m_feature.Extent.XMin) / 2;
            double midY = (m_feature.Extent.YMax + m_feature.Extent.YMin) / 2;
            IPoint pPoint = new PointClass();
            pPoint.SpatialReference = m_feature.Extent.SpatialReference;
            pPoint.PutCoords(midX, midY);
            pPoint.Project(activeView.Extent.SpatialReference);

            IEnvelope pCurrentEnvelope = activeView.Extent;
            pCurrentEnvelope.CenterAt(pPoint);

            activeView.Extent = pCurrentEnvelope;
            activeView.Refresh();
            activeView.ScreenDisplay.UpdateWindow();

            IFeatureIdentifyObj featIdentify = new FeatureIdentifyObject();
            featIdentify.Feature = m_feature;
            IIdentifyObj identify = featIdentify as IIdentifyObj;
            identify.Flash(activeView.ScreenDisplay);
        }

Re: Programatically PanTo / ZoomTo and then Flash features

HalilSiddique — Wed, 21 Mar 2012 13:09:14 GMT

I was having the same problem, I'm glad I found this post.

Re: Programatically PanTo / ZoomTo and then Flash features

zhenliu — Sat, 24 May 2014 10:40:23 GMT

I am glad to find the solution!

Re: Programatically PanTo / ZoomTo and then Flash features

ZLIU — Wed, 24 Jun 2015 01:33:44 GMT

Worked for me! Thanks!