Latest Contributions by MarkCederholm

Now that ArcGIS Runtime SDK supports annotation in mobile map packages, it would be nice to expose some more functionality.  In particular, it would be useful to be able to change the color. ... View more

Well!  In my previous article, I presented a workaround for a bizarre MMPK bug that reappeared in version 100.5 of the ArcGIS Runtime SDK for .NET; but just when I thought I couldn't find another one even more unthinkably bizarre, up pops this: QueryRelatedFeaturesAsync will return a bad result when the FeatureLayer of a GeodatabaseFeatureTable is a sublayer of a GroupLayer. Huh?  You can check out the attached Visual Studio project for confirmation, but in the meantime we have a conundrum.  It would appear that, just when the GroupLayer class is finally implemented, we have to chuck it right back out until a safer, more effective version is delivered.  I've updated an earlier article of mine to reflect that situation.  Nonetheless, I got to thinking about how Runtime support for querying M:N relationships in a mobile map package didn't even start to appear until 100.4, and what I would need to do in order to support them were I still stuck at 100.3. Or, what if QueryRelatedFeaturesAsync were to fail again in a future version? Supporting one-to-one and one-to-many relationships is actually fairly simple, since the RelationshipInfo class gives the required information, when retrieved from both origin and destination tables.  But many-to-many relationships are entirely another can of worms, because some crucial information is inaccessible via Runtime, even though it's encoded in the geodatabase. Contrary to the wording in the documentation for the RelationshipInfo class [and I quote: "A relationship consists of two and only two tables"], M:N relationships involve a third, intermediate table.  Querying M:N relationships requires knowledge to query that intermediate table, and that's precisely the information which is withheld from the Runtime developer. Let's take a look at how relationships are stored in a mobile map package.  In my previous article, I introduced you to the GDB_ServiceItems table.  The ItemInfo field in that table stores the JSON data used to hydrate the ArcGISFeatureLayerInfo class:     Here's the JSON that describes the RegulatorStation to GasValve relationship from the origin role:     { "id": 4, "name": "Gas Valve", "relatedTableId": 10, "cardinality": "esriRelCardinalityManyToMany", "role": "esriRelRoleOrigin", "keyField": "OBJECTID", "composite": false, "relationshipTableId": 73, "keyFieldInRelationshipTable": "REGSTATIONOBJECTID" }‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍     And here's the description for destination role:     { "id": 4, "name": "Regulator Station", "relatedTableId": 13, "cardinality": "esriRelCardinalityManyToMany", "role": "esriRelRoleDestination", "keyField": "OBJECTID", "composite": false, "relationshipTableId": 73, "keyFieldInRelationshipTable": "GASVALVEOBJECTID" }‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍     The two crucial items that are not included in the RelationshipInfo class are relationshipTableId and keyFieldInRelationshipTable.  But how to get at that information in your app?  Aye, there's the rub.  In short, you need to extract the geodatabase from the mobile map package and query the GDB_ServiceItems table directly.  That's where you need a library such as System.Data.SQLite, which is available via the NuGet Package Manager:     Given the necessary tools, the first step is to extract the geodatabase to a temporary location:     public async Task Init(string sMMPKPath, Geodatabase gdb) { string sGDBPath = gdb.Path; string sGDBName = Path.GetFileName(sGDBPath); string sTempDir = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString()); Directory.CreateDirectory(sTempDir); string sTempPath = Path.Combine(sTempDir, sGDBName); using (ZipArchive zip = ZipFile.OpenRead(sMMPKPath)) { ZipArchiveEntry zipEntry = zip.GetEntry(sGDBPath); zipEntry.ExtractToFile(sTempPath); } ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍     Next, query the desired information, taking the steps necessary to clean up afterwards:     List<string> ItemInfos = new List<string>(); string sConn = "Data Source=" + sTempPath + ";Read Only=True"; string sSQL = "SELECT ItemInfo FROM GDB_ServiceItems"; using (SQLiteConnection sqlConn = new SQLiteConnection("Data Source=" + sTempPath)) { sqlConn.Open(); using (SQLiteCommand sqlCmd = new SQLiteCommand(sSQL, sqlConn)) { using (SQLiteDataReader sqlReader = sqlCmd.ExecuteReader()) { while (sqlReader.Read()) ItemInfos.Add(sqlReader.GetString(0)); sqlReader.Close(); } } sqlConn.Close(); } GC.Collect(); GC.WaitForPendingFinalizers(); Directory.Delete(sTempDir, true); ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍     Finally, combine the missing ingredients with the out-of-the-box information:     _infos = new Dictionary<long, Dictionary<long, ExtendedRelationshipInfo>>(); foreach (string sInfo in ItemInfos) { Dictionary<string, object> info = _js.DeserializeObject(sInfo) as Dictionary<string, object>; if (!info.ContainsKey("relationships")) continue; object[] relationships = info["relationships"] as object[]; if (relationships.Length == 0) continue; long iTableID = Convert.ToInt64(info["id"]); // Get basic table relationship infos GeodatabaseFeatureTable gfTab = gdb.GeodatabaseFeatureTable(iTableID); if (gfTab.LoadStatus != Esri.ArcGISRuntime.LoadStatus.Loaded) await gfTab.LoadAsync(); Dictionary<long, RelationshipInfo> BasicInfos = new Dictionary<long, RelationshipInfo>(); foreach (RelationshipInfo relInfo in gfTab.LayerInfo.RelationshipInfos) BasicInfos[relInfo.Id] = relInfo; // Add extended data Dictionary<long, ExtendedRelationshipInfo> ExtendedInfos = new Dictionary<long, ExtendedRelationshipInfo>(); foreach (object obj in relationships) { Dictionary<string, object> rel = obj as Dictionary<string, object>; long iRelID = Convert.ToInt64(rel["id"]); string sCard = rel["cardinality"].ToString(); long? iRelTableID = null; string sKeyField = null; if (sCard == "esriRelCardinalityManyToMany") { iRelTableID = Convert.ToInt64(rel["relationshipTableId"]); sKeyField = rel["keyFieldInRelationshipTable"].ToString(); } ExtendedRelationshipInfo erInfo = new ExtendedRelationshipInfo() { BasicInfo = BasicInfos[iRelID], RelationshipTableId = iRelTableID, KeyFieldInRelationshipTable = sKeyField }; ExtendedInfos[iRelID] = erInfo; } _infos[iTableID] = ExtendedInfos; } // foreach ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍     Here, then, is the code for querying related features:     public async Task<FeatureQueryResult> QueryRelated(ArcGISFeature feat, long iRelID) { // Get relationship data if (!(feat.FeatureTable is GeodatabaseFeatureTable gfTabSource)) return null; long iTableID = gfTabSource.LayerInfo.ServiceLayerId; if (!_infos.ContainsKey(iTableID)) return null; Dictionary<long, ExtendedRelationshipInfo> ExtendedInfos = _infos[iTableID]; if (!ExtendedInfos.ContainsKey(iRelID)) return null; ExtendedRelationshipInfo extInfoSource = ExtendedInfos[iRelID]; RelationshipInfo infoSource = extInfoSource.BasicInfo; long iRelTableID = infoSource.RelatedTableId; if (!_infos.ContainsKey(iRelTableID)) return null; ExtendedInfos = _infos[iRelTableID]; if (!ExtendedInfos.ContainsKey(iRelID)) return null; ExtendedRelationshipInfo extInfoTarget = ExtendedInfos[iRelID]; RelationshipInfo infoTarget = extInfoTarget.BasicInfo; // Build query string sKeyValSource = feat.GetAttributeValue(infoSource.KeyField).ToString(); Geodatabase gdb = gfTabSource.Geodatabase; GeodatabaseFeatureTable gfTabTarget = gdb.GeodatabaseFeatureTable(iRelTableID); string sKeyFieldTarget = infoTarget.KeyField; Field fieldKeyTarget = gfTabTarget.GetField(sKeyFieldTarget); StringBuilder sb = new StringBuilder(); sb.Append(sKeyFieldTarget); if (infoSource.Cardinality == RelationshipCardinality.ManyToMany) { // Gather key values from intermediate table GeodatabaseFeatureTable gfTabRel = gdb.GeodatabaseFeatureTable(extInfoSource.RelationshipTableId.Value); string sKeyFieldRelSource = extInfoSource.KeyFieldInRelationshipTable; Field fieldRelSource = gfTabRel.GetField(sKeyFieldRelSource); string sWhere = sKeyFieldRelSource + " = " + sKeyValSource; if (fieldRelSource.FieldType == FieldType.Guid) sWhere = sKeyFieldRelSource + " = '" + sKeyValSource + "'"; QueryParameters qpRel = new QueryParameters() { WhereClause = sWhere }; FeatureQueryResult resultRel = await gfTabRel.QueryFeaturesAsync(qpRel); if (resultRel.Count() == 0) return resultRel; string sKeyFieldRelTarget = extInfoTarget.KeyFieldInRelationshipTable; Field fieldRelTarget = gfTabRel.GetField(sKeyFieldRelTarget); sb.Append(" IN ( "); bool bFirst = true; foreach (Feature featRel in resultRel) { if (bFirst) bFirst = false; else sb.Append(", "); string sKeyValTarget = featRel.GetAttributeValue(sKeyFieldRelTarget).ToString(); if (fieldRelTarget.FieldType == FieldType.Guid) sb.Append("'" + sKeyValTarget + "'"); else sb.Append(sKeyValTarget); } sb.Append(" ) "); } else { sb.Append(" = "); if (fieldKeyTarget.FieldType == FieldType.Guid) sb.Append("'" + sKeyValSource + "'"); else sb.Append(sKeyValSource); } // Query related features QueryParameters qp = new QueryParameters() { WhereClause = sb.ToString() }; return await gfTabTarget.QueryFeaturesAsync(qp); }‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍     Needless to say, this is a pretty extreme approach to take.  Nonetheless, you never know when this knowledge may come in useful.     UPDATE:   It occurred to me that since I routinely automate MMPK creation using Python, I could also create companion files containing the many-to-many relationships.  I've added a new attachment that contains both a Python script and a revised version of the RelationshipHelper class that takes advantage of it.  Now it's more feasible to support both group layers and related feature queries.   ... 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In my previous article, I presented a workaround for preserving group layers in a mobile map opened using ArcGIS Runtime SDK for .NET 100.5.  Today's topic involves something a bit nastier.  It can be pretty frustrating when a bug that is fixed in an earlier software version reappears in a later one.  The lesson here is: Never discard your workaround code! The bug in question involves certain multi-layer marker symbols that are not rendered properly when rotated.  For example, see this symbol as shown in the original ArcGIS Pro project:     Here's how it looks when exported to a mobile map package and opened using ArcGIS Runtime (see the attached Visual Studio example project):     Yikes!  This problem was identified at 100.1 and fixed in 100.2, but at 100.5 once more it rears its ugly head.  One workaround is to set ArcGISFeatureTable.UseAdvancedSymbology to false.  This causes marker symbols to be rendered as picture markers.  That's fine until you run into two limitations.  The first is when you set a reference scale and zoom in:     But even more challenging, what if you want to change symbol colors on the fly?  In theory, you can do that with a bitmap, but it's beyond my skill to deal with the dithering:     There's another approach, but until Esri implements more fine-grained class properties and methods, manipulating symbols involves a lot of JSON hacking.  Before I go any further, let's crack open a mobile map package and see where drawing information is stored.  If you examine the mobile geodatabase using a tool such as SQLiteSpy, you will see a table called GDB_ServiceItems:     That's the raw JSON for the data retrieved by ArcGISFeatureTable.LayerInfo.DrawingInfo.  Fortunately, there's no need to hack into the table, because you can get the renderer for a feature layer, retrieve the symbol(s), and convert them to JSON.  Then you make whatever edits you want, and create a new symbol.   public static Symbol UpdateSymbolJSON(MultilayerPointSymbol symOld, Color colorOld, Color colorNew) { string sOldJSON = symOld.ToJson(); Dictionary<string, object> dict = (Dictionary<string, object>)_js.DeserializeObject(sOldJSON); SymbolHelper.ProcessObjectColorJSON(dict, colorOld, colorNew); string sNewJSON = _js.Serialize(dict); Symbol symNew = Symbol.FromJson(sNewJSON); return symNew; } ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍   So what's the workaround?  The nature of the bug seems to be an inability to process offsetX and offsetY correctly.  In fact, they seem to be reversed.  So let's see what happens when the offsets are reversed in the JSON:     Nope.  Not quite there.  What I finally ended up doing is to combine the offset layers into a single layer with no offsets.  Fortunately again, characters are already converted to polygons in the JSON, or I would be doing a lot more work.  First, I collect the offset layers and find the smallest interval (points per coordinate unit):   bool[] Offset = new bool[layers.Length]; List<OffsetLayer> OffsetLayers = new List<OffsetLayer>(); double dInterval = double.MaxValue; for (int i = 0; i < layers.Length; i++) { Dictionary<string, object> lyr = layers[i] as Dictionary<string, object>; // Check for X and/or Y offset bool bOffset = false; double dOffsetX = 0; double dOffsetY = 0; if (lyr.ContainsKey("offsetX")) { dOffsetX = Convert.ToDouble(lyr["offsetX"]); lyr["offsetX"] = 0; bOffset = true; } if (lyr.ContainsKey("offsetY")) { dOffsetY = Convert.ToDouble(lyr["offsetY"]); lyr["offsetY"] = 0; bOffset = true; } Offset[i] = bOffset; if (!bOffset) continue; // Get offset layer data Dictionary<string, object> frame = lyr["frame"] as Dictionary<string, object>; object[] markerGraphics = lyr["markerGraphics"] as object[]; Dictionary<string, object> markerGraphic = markerGraphics[0] as Dictionary<string, object>; Dictionary<string, object> geometry = markerGraphic["geometry"] as Dictionary<string, object>; object[] rings = geometry["rings"] as object[]; int ymin = Convert.ToInt32(frame["ymin"]); int ymax = Convert.ToInt32(frame["ymax"]); double size = Convert.ToDouble(lyr["size"]); double dInt = size / (ymax - ymin); if (dInt < dInterval) dInterval = dInt; OffsetLayer layer = new OffsetLayer() { offsetX = dOffsetX, offsetY = dOffsetY, xmin = Convert.ToInt32(frame["xmin"]), ymin = ymin, xmax = Convert.ToInt32(frame["xmax"]), ymax = ymax, size = size, rings = rings }; OffsetLayers.Add(layer); } // for ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍   Then I set up the combined frame and recalculate the ring coordinates:   int iMinX = 0; int iMinY = 0; int iMaxX = 0; int iMaxY = 0; List<object[]> OffsetRings = new List<object[]>(); foreach (OffsetLayer lyr in OffsetLayers) { double dX, dY; int iX, iY; // Set up transformation double dInt = lyr.size / (lyr.ymax - lyr.ymin); double dOffsetX = lyr.offsetX / dInt; double dOffsetY = lyr.offsetY / dInt; double dScale = dInt / dInterval; dX = (lyr.xmin + dOffsetX) * dScale; iX = (int)dX; if (iX < iMinX) iMinX = iX; dX = (lyr.xmax + dOffsetX) * dScale; iX = (int)dX; if (iX > iMaxX) iMaxX = iX; dY = (lyr.ymin + dOffsetY) * dScale; iY = (int)dY; if (iY < iMinY) iMinY = iY; dY = (lyr.ymax + dOffsetY) * dScale; iY = (int)dY; if (iY > iMaxY) iMaxY = iY; // Recalculate rings foreach (object obj in lyr.rings) { object[] ring = obj as object[]; foreach (object o in ring) { object[] pt = o as object[]; pt[0] = (int)((Convert.ToInt32(pt[0]) + dOffsetX) * dScale); pt[1] = (int)((Convert.ToInt32(pt[1]) + dOffsetY) * dScale); } OffsetRings.Add(ring); } } // foreach double dSize = (iMaxY - iMinY) * dInterval; ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍   Finally, I assemble a new symbol layer list:   List<object> NewLayers = new List<object>(); bool bFirst = true; for (int i = 0; i < layers.Length; i++) { if (!Offset[i]) { NewLayers.Add(layers[i]); continue; } else if (!bFirst) continue; // Update first offset layer Dictionary<string, object> lyr = layers[i] as Dictionary<string, object>; Dictionary<string, object> frame = lyr["frame"] as Dictionary<string, object>; frame["xmin"] = iMinX; frame["ymin"] = iMinY; frame["xmax"] = iMaxX; frame["ymax"] = iMaxY; lyr["size"] = dSize; if (lyr.ContainsKey("offsetX")) lyr["offsetX"] = 0; if (lyr.ContainsKey("offsetY")) lyr["offsetY"] = 0; NewLayers.Add(lyr); object[] markerGraphics = lyr["markerGraphics"] as object[]; Dictionary<string, object> markerGraphic = markerGraphics[0] as Dictionary<string, object>; Dictionary<string, object> geometry = markerGraphic["geometry"] as Dictionary<string, object>; geometry["rings"] = OffsetRings.ToArray(); bFirst = false; } // for return NewLayers.ToArray(); ‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍‍   And here are the results:     Much better.  I can't guarantee that this code will work for every situation, but it seems to work fine for my own complex symbols.  And remember:  even if this bug is fixed at 100.6, hang onto this code, in case you need it again in the future!   ... 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I notice that Arcade expressions for display fields don't come across in a mobile map package.  However, this is a very minor issue, since I can use the same expression in the popup title and it works fine.  It's nice to use PopupManager and see subtype and domain values displaying properly. ... View more

I notice that the GroupLayer class at 100.5 has a quirk similar that of an earlier (pre-10.2.7) release:  when a sublayer has labels enabled and the group layer is initially not visible, the labels still appear.  However, when the layer is made visible and then not visible again, the labels go away.  Is there a better practice for creating and adding group layers? ... View more