topic Re: Callout text overlapping in ArcObjects SDK Questions

Callout text overlapping

JonathanMeyer — Fri, 08 Jul 2011 14:17:52 GMT

Anyone I have any suggestions on how to add some conflict detection for text callouts? I have a custom tool that labels certain features a user has selected. The problem is when these features are close together the labels overlap and must be moved by the user. I am arbitrarily setting an offset for the callouts from the features when creating them so they will display away from the feature. However, I can???t find an easy way to determine if the callout will overlap another callout before placing it on the map.

Re: Callout text overlapping

JonathanMeyer — Wed, 20 Jul 2011 19:24:13 GMT

Ok, so no help.

How bout can someone help me figure out the extent of the callout balloon text so I can at least try and figure out where these things are or should go on the map. Using QueryBounds on the element it�??s not giving me the extent of the callout text. It appears to be returning something that�??s close to the location of anchor point associated with the callout but not exactly.

Re: Callout text overlapping

JeffreyHamblin — Wed, 20 Jul 2011 23:20:15 GMT

Can you post some code that shows how you are constructing and placing the callout element?

Re: Callout text overlapping

JonathanMeyer — Thu, 21 Jul 2011 11:51:52 GMT

I have simiplified this a little bit to post here but you should be able to get the idea:


            double fromX = centerline.FromPoint.X;
            double fromY = centerline.FromPoint.Y;

            ITextElement leftFromTextElement = new TextElementClass();
            IElement leftFromElement = leftFromTextElement as IElement;
            IElementProperties leftFromProperties = leftFromElement as IElementProperties;
            leftFromProperties.Name = "LF:" + OID.ToString();
            leftFromTextElement.Text = "LF " + LeftAddressFrom.ToString();

            ESRI.ArcGIS.Geometry.Point point = new ESRI.ArcGIS.Geometry.Point();

            point.PutCoords(fromX, fromY + mOffset);
            leftFromElement.Geometry = point;

            // Create text symbology
            IFormattedTextSymbol textSymLeftAlign = new TextSymbol() as IFormattedTextSymbol;
            stdole.IFontDisp fontFrom = textSymLeftAlign.Font;
            fontFrom.Size = 8;
            textSymLeftAlign.Font = fontFrom;
            textSymLeftAlign.HorizontalAlignment = esriTextHorizontalAlignment.esriTHALeft;

            ICallout callOut = new BalloonCalloutClass();
            textSymLeftAlign.Background = (ITextBackground)callOut;

            // Set anchor point
            ESRI.ArcGIS.Geometry.Point anchorPTFrom = new ESRI.ArcGIS.Geometry.Point();
            anchorPTFrom.PutCoords(fromX, fromY);
            callOut.AnchorPoint = anchorPTFrom;

            leftFromTextElement.Symbol = textSymLeftAlign;

            IGraphicsContainer graphicsContainer = mMxDoc.ActivatedView as IGraphicsContainer;
            graphicsContainer.AddElement(leftFromElement, 0);
            leftFromElement.Activate(mMxDoc.ActivatedView.ScreenDisplay);

   //Testing to see if I can figure out extent of callout graphic
   IEnvelope elementEnvelope = new EnvelopeClass();
   leftFromElement.QueryBounds(mMxDoc.ActiveView.ScreenDisplay,elementEnvelope);

Re: Callout text overlapping

JeffreyHamblin — Fri, 10 Dec 2021 21:01:18 GMT

I put your code into a test Add-In and made as few modifications as needed to get it to run (just some constant values and document references):


public void PerformTest()
{
    double fromX = 0;
    double fromY = 0;

    ITextElement leftFromTextElement = new TextElementClass();
    IElement leftFromElement = leftFromTextElement as IElement;
    IElementProperties leftFromProperties = leftFromElement as IElementProperties;
    leftFromProperties.Name = "LF:" + "TEST";
    leftFromTextElement.Text = "Sample text to go in a callout to test gettting the size. " +
            "\r\nThis adds some text on a second line." +
            "\r\nThis adds some text on a third line.";


    ESRI.ArcGIS.Geometry.Point point = new ESRI.ArcGIS.Geometry.Point();

    point.PutCoords(fromX, fromY + 0);
    leftFromElement.Geometry = point;


    // Create text symbology
    IFormattedTextSymbol textSymLeftAlign = new TextSymbol() as IFormattedTextSymbol;
    stdole.IFontDisp fontFrom = textSymLeftAlign.Font;
    fontFrom.Size = 8;
    textSymLeftAlign.Font = fontFrom;
    textSymLeftAlign.HorizontalAlignment = esriTextHorizontalAlignment.esriTHALeft;

    ICallout callOut = new BalloonCalloutClass();
    textSymLeftAlign.Background = (ITextBackground)callOut;

    // Set anchor point
    ESRI.ArcGIS.Geometry.Point anchorPTFrom = new ESRI.ArcGIS.Geometry.Point();
    anchorPTFrom.PutCoords(fromX, fromY);
    callOut.AnchorPoint = anchorPTFrom;


    leftFromTextElement.Symbol = textSymLeftAlign;

    IGraphicsContainer graphicsContainer = ArcMap.Document.ActivatedView as IGraphicsContainer;
    graphicsContainer.AddElement(leftFromElement, 0);
    leftFromElement.Activate(ArcMap.Document.ActivatedView.ScreenDisplay);

    //Testing to see if I can figure out extent of callout graphic
    IEnvelope elementEnvelope = new EnvelopeClass();
    leftFromElement.QueryBounds(ArcMap.Document.ActiveView.ScreenDisplay, elementEnvelope);

    System.Diagnostics.Debug.WriteLine("Element: " + elementEnvelope.Width + ", " + elementEnvelope.Height);
}

The output in Page Layout is:
Element: 2.85220000000118, 0.530399999999645

The output in Data View is:
Element: 6608.73942823708, 1228.99884448946

These look to me to correspond to the width and height of the callout box. Isn't that what you are looking for?

Re: Callout text overlapping

JonathanMeyer — Fri, 10 Dec 2021 21:01:20 GMT

I put your code into a test Add-In and made as few modifications as needed to get it to run (just some constant values and document references):


public void PerformTest()
{
    double fromX = 0;
    double fromY = 0;

    ITextElement leftFromTextElement = new TextElementClass();
    IElement leftFromElement = leftFromTextElement as IElement;
    IElementProperties leftFromProperties = leftFromElement as IElementProperties;
    leftFromProperties.Name = "LF:" + "TEST";
    leftFromTextElement.Text = "Sample text to go in a callout to test gettting the size. " +
            "\r\nThis adds some text on a second line." +
            "\r\nThis adds some text on a third line.";


    ESRI.ArcGIS.Geometry.Point point = new ESRI.ArcGIS.Geometry.Point();

    point.PutCoords(fromX, fromY + 0);
    leftFromElement.Geometry = point;


    // Create text symbology
    IFormattedTextSymbol textSymLeftAlign = new TextSymbol() as IFormattedTextSymbol;
    stdole.IFontDisp fontFrom = textSymLeftAlign.Font;
    fontFrom.Size = 8;
    textSymLeftAlign.Font = fontFrom;
    textSymLeftAlign.HorizontalAlignment = esriTextHorizontalAlignment.esriTHALeft;

    ICallout callOut = new BalloonCalloutClass();
    textSymLeftAlign.Background = (ITextBackground)callOut;

    // Set anchor point
    ESRI.ArcGIS.Geometry.Point anchorPTFrom = new ESRI.ArcGIS.Geometry.Point();
    anchorPTFrom.PutCoords(fromX, fromY);
    callOut.AnchorPoint = anchorPTFrom;


    leftFromTextElement.Symbol = textSymLeftAlign;

    IGraphicsContainer graphicsContainer = ArcMap.Document.ActivatedView as IGraphicsContainer;
    graphicsContainer.AddElement(leftFromElement, 0);
    leftFromElement.Activate(ArcMap.Document.ActivatedView.ScreenDisplay);

    //Testing to see if I can figure out extent of callout graphic
    IEnvelope elementEnvelope = new EnvelopeClass();
    leftFromElement.QueryBounds(ArcMap.Document.ActiveView.ScreenDisplay, elementEnvelope);

    System.Diagnostics.Debug.WriteLine("Element: " + elementEnvelope.Width + ", " + elementEnvelope.Height);
}

If you go to the coordinates returned for upper left/right, lower left/right on the elementEnvelope they aren't the four points of the callout box. They aren't even close.

Re: Callout text overlapping

JeffreyHamblin — Fri, 10 Dec 2021 21:01:23 GMT

Running same test code as before. The corner location coordinates are correct in Layout View:

Element Size: 2.85220000000118, 0.530399999999645
UpperLeft:-0.0694000000003143, 0.436700000000201
LowerLeft:-0.0694000000003143, -0.0936999999994441
UpperRight:2.78280000000086, 0.436700000000201
LowerRight:2.78280000000086, -0.0936999999994441

I added this to get the spatial ref and corners:

System.Diagnostics.Debug.WriteLine("  SpatialReference: " + (leftFromTextElement as IGraphicElement).SpatialReference.Name);
System.Diagnostics.Debug.WriteLine("  UpperLeft:" + elementEnvelope.UpperLeft.X + ", " + elementEnvelope.UpperLeft.Y);
System.Diagnostics.Debug.WriteLine("  LowerLeft:" + elementEnvelope.LowerLeft.X + ", " + elementEnvelope.LowerLeft.Y);
System.Diagnostics.Debug.WriteLine("  UpperRight:" + elementEnvelope.UpperRight.X + ", " + elementEnvelope.UpperRight.Y);
System.Diagnostics.Debug.WriteLine("  LowerRight:" + elementEnvelope.LowerRight.X + ", " + elementEnvelope.LowerRight.Y);

In Data View :
Element Size: 6608.73942823708, 1228.99884448946
SpatialReference: NAD_1983_StatePlane_California_VI_FIPS_0406_Feet
UpperLeft:-160.905063271523, 1011.83200590312
LowerLeft:-160.905063271523, -217.16683858633
UpperRight:6447.83436496556, 1011.83200590312
LowerRight:6447.83436496556, -217.16683858633

Using the Go To XY (set to Feet like the SR), and it located the corners correctly.

Re: Callout text overlapping

JonathanMeyer — Fri, 10 Dec 2021 21:01:26 GMT

Running same test code as before. The corner location coordinates are correct in Layout View:

Element Size: 2.85220000000118, 0.530399999999645
UpperLeft:-0.0694000000003143, 0.436700000000201
LowerLeft:-0.0694000000003143, -0.0936999999994441
UpperRight:2.78280000000086, 0.436700000000201
LowerRight:2.78280000000086, -0.0936999999994441

I added this to get the spatial ref and corners:
System.Diagnostics.Debug.WriteLine("  SpatialReference: " + (leftFromTextElement as IGraphicElement).SpatialReference.Name);
System.Diagnostics.Debug.WriteLine("  UpperLeft:" + elementEnvelope.UpperLeft.X + ", " + elementEnvelope.UpperLeft.Y);
System.Diagnostics.Debug.WriteLine("  LowerLeft:" + elementEnvelope.LowerLeft.X + ", " + elementEnvelope.LowerLeft.Y);
System.Diagnostics.Debug.WriteLine("  UpperRight:" + elementEnvelope.UpperRight.X + ", " + elementEnvelope.UpperRight.Y);
System.Diagnostics.Debug.WriteLine("  LowerRight:" + elementEnvelope.LowerRight.X + ", " + elementEnvelope.LowerRight.Y);
In Data View :
Element Size: 6608.73942823708, 1228.99884448946
SpatialReference: NAD_1983_StatePlane_California_VI_FIPS_0406_Feet
UpperLeft:-160.905063271523, 1011.83200590312
LowerLeft:-160.905063271523, -217.16683858633
UpperRight:6447.83436496556, 1011.83200590312
LowerRight:6447.83436496556, -217.16683858633

Using the Go To XY (set to Feet like the SR), and it located the corners correctly.

Ok yes I agree the code you have works and is returning the 4 corners. However, try changing your offset value for Y on the leftFromElement.Geometry to something other then 0. This way the actual callout appears away from the anchor point and will show the tail of the callout. Then see if the returned coordinates match the corners of the box.

Re: Callout text overlapping

JeffreyHamblin — Thu, 21 Jul 2011 19:50:25 GMT

Ok yes I agree the code you have works and is returning the 4 corners. However, try changing your offset value for Y on the leftFromElement.Geometry to something other then 0. This way the actual callout appears away from the anchor point and will show the tail of the callout. Then see if the returned coordinates match the corners of the box.

Yeah, it looks like it returns the envelope surrounding the anchor and the balloon -- which makes sense since the element includes both.

Have you tried ITextBackground.QueryBoundary? Since the background is the ballooncallout, it seems like that should work. I don't have time to test it at the moment...

Re: Callout text overlapping

JonathanMeyer — Thu, 21 Jul 2011 21:11:34 GMT

Yeah, it looks like it returns the envelope surrounding the anchor and the balloon -- which makes sense since the element includes both.

Have you tried ITextBackground.QueryBoundary? Since the background is the ballooncallout, it seems like that should work. I don't have time to test it at the moment...

No, I'll give that a shot tomorrow see if it works.

Re: Callout text overlapping

JonathanMeyer — Fri, 22 Jul 2011 12:46:50 GMT

It seems like ITextBackground.QueryBoundary should work but I'm getting an empty geometry returned. I appreciate all the help by the way.

Re: Callout text overlapping

JeffreyHamblin — Fri, 10 Dec 2021 21:01:28 GMT

It seems like ITextBackground.QueryBoundary should work but I'm getting an empty geometry returned. I appreciate all the help by the way.

I got the same thing (empty geometry) using:


IPolygon poly = new PolygonClass();
textSymLeftAlign.Background.QueryBoundary(ArcMap.Document.ActiveView.ScreenDisplay.get_CacheMemDC(0),
    ArcMap.Document.ActiveView.ScreenDisplay.DisplayTransformation as ITransformation,
    poly);
System.Diagnostics.Debug.WriteLine("Background: " + poly.Envelope.Width + ", " + poly.Envelope.Height);

Looking at the object model, there is another to try: IQueryGeometry.QueryEnvelope. Implemented by BalloonCallout.

I wish I could be more direct help, but I'm trying to figure this one out too. Hopefully we'll nail it in the end.

Re: Callout text overlapping

JeffreyHamblin — Fri, 10 Dec 2021 21:01:31 GMT

Well... I spent some time with IQueryGeometry.QueryEnvelope and keep getting "method or operation not implemented".

I would think there is a way to get the balloon callout's envelope directly, but if you can't get it to work -- or if someone else doesn't jump into this thread with the solution -- I found a cludgy way to get it: First place the element without an anchor and get the bounds of the callout. Then add the anchor.

public void PerformTest()
{

    double fromX = 0;
    double fromY = 0;

    ITextElement textElement = new TextElementClass();
    IElement element = textElement as IElement;
    IElementProperties elementProperties = element as IElementProperties;

    textElement.Text = "Sample text to go in a callout to test getting the size. " +
            "\r\nThis adds some text on a second line." +
            "\r\nThis adds some text on a third line.";


    ESRI.ArcGIS.Geometry.Point point = new ESRI.ArcGIS.Geometry.Point();

    double offSetX = 0;
    double offSetY = 0;
    if (ArcMap.Document.ActivatedView is IPageLayout)
    {
        // inches, page layout units
        offSetX = 0.5;
        offSetY = 1;
    }
    else
    {
        // feet. This worked for my test map's scale.
        offSetX = 800;
        offSetY = 1500;
    }

    // Set the location of the callout balloon (lower-left corner of text)
    point.PutCoords(fromX + offSetX, fromY + offSetY);
    element.Geometry = point;


    // Create text symbology
    IFormattedTextSymbol formattedTextSymbol = new TextSymbol() as IFormattedTextSymbol;
    stdole.IFontDisp fontFrom = formattedTextSymbol.Font;
    fontFrom.Size = 8;
    formattedTextSymbol.Font = fontFrom;
    formattedTextSymbol.HorizontalAlignment = esriTextHorizontalAlignment.esriTHALeft;

    ICallout callOut = new BalloonCalloutClass();
    formattedTextSymbol.Background = (ITextBackground)callOut;

    textElement.Symbol = formattedTextSymbol;
    
    IGraphicsContainer graphicsContainer = ArcMap.Document.ActivatedView as IGraphicsContainer;

    // Add the callout element without a leader to an anchor point
    graphicsContainer.AddElement(element, 0);

    // Get the bounds of callout envelope for just the balloon
    IEnvelope elementEnvelope = new EnvelopeClass();
    element.QueryBounds(ArcMap.Document.ActiveView.ScreenDisplay, elementEnvelope);

    System.Diagnostics.Debug.WriteLine("Element (Before Anchor): " + elementEnvelope.Width + ", " + elementEnvelope.Height);
    System.Diagnostics.Debug.WriteLine("  SpatialReference: " + (textElement as IGraphicElement).SpatialReference.Name);
    System.Diagnostics.Debug.WriteLine("  UpperLeft:" + elementEnvelope.UpperLeft.X + ", " + elementEnvelope.UpperLeft.Y);
    System.Diagnostics.Debug.WriteLine("  LowerLeft:" + elementEnvelope.LowerLeft.X + ", " + elementEnvelope.LowerLeft.Y);
    System.Diagnostics.Debug.WriteLine("  UpperRight:" + elementEnvelope.UpperRight.X + ", " + elementEnvelope.UpperRight.Y);
    System.Diagnostics.Debug.WriteLine("  LowerRight:" + elementEnvelope.LowerRight.X + ", " + elementEnvelope.LowerRight.Y);

    // Set the leader anchor point
    ESRI.ArcGIS.Geometry.Point anchorPTFrom = new ESRI.ArcGIS.Geometry.Point();
    anchorPTFrom.PutCoords(fromX, fromY);
    callOut.AnchorPoint = anchorPTFrom;

    // Must re-assign this or leader to anchor is not created on map and querybounds
    // returns same value as before
    textElement.Symbol = formattedTextSymbol;

    // Get the bounds of the entire callout envelope surrounding balloon and leader
    element.QueryBounds(ArcMap.Document.ActiveView.ScreenDisplay, elementEnvelope);

    System.Diagnostics.Debug.WriteLine("Element (After Anchor): " + elementEnvelope.Width + ", " + elementEnvelope.Height);
    System.Diagnostics.Debug.WriteLine("  SpatialReference: " + (textElement as IGraphicElement).SpatialReference.Name);
    System.Diagnostics.Debug.WriteLine("  UpperLeft:" + elementEnvelope.UpperLeft.X + ", " + elementEnvelope.UpperLeft.Y);
    System.Diagnostics.Debug.WriteLine("  LowerLeft:" + elementEnvelope.LowerLeft.X + ", " + elementEnvelope.LowerLeft.Y);
    System.Diagnostics.Debug.WriteLine("  UpperRight:" + elementEnvelope.UpperRight.X + ", " + elementEnvelope.UpperRight.Y);
    System.Diagnostics.Debug.WriteLine("  LowerRight:" + elementEnvelope.LowerRight.X + ", " + elementEnvelope.LowerRight.Y);
}

Re: Callout text overlapping

JonathanMeyer — Mon, 25 Jul 2011 11:27:22 GMT

Thats the same thing I was seeing Friday. I figured I wasn't calling it correctly and was going to look at it again today.

Re: Callout text overlapping

kyleknoche — Thu, 04 Aug 2011 20:38:28 GMT

Did anyone figure this thing out yet?

I have balloon callouts that I just cannot get the shape for. I've tried everything and nothing works.

Re: Callout text overlapping

JonathanMeyer — Fri, 05 Aug 2011 11:27:18 GMT

Did anyone figure this thing out yet?

I have balloon callouts that I just cannot get the shape for. I've tried everything and nothing works.

I ended up giving up and using the Maplex extension for what I needed to do. Everything I tried ended up returning an empty geometry or method not implemented. One would think this should be possible but it's sure not documented anywhere.

If anyone does figure it out I also would be interested to know for future use.