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Migrating from v13 to v14

#1

Hi,

I am trying to migrate ThinkGEO XamarinForms to MAUI, it seems the implementation has changed.
Not sure what to do to make the previous code work…

  1. Setting Current Extent
    In v13, we could set the CurrentExtent as below.
    mapView.CurrentExtent = myCustomExtent;
    In v14, CurrentExtent setter seem to be hided. How could I set it in v14?

  2. Touch/Tap event
    In v13, we have below event handlers and the args is TouchMapViewEventArgs

    mapView.MapSingleTap -= mapView_MapClick;
    mapView.MapSingleTap += mapView_MapClick;

    mapView.MapDoubleTap -= mapView_MapDoubleClick;
    mapView.MapDoubleTap += mapView_MapDoubleClick;

But in v14, I think they have changed to
mapView.SingleTap -= mapView_MapClick;
mapView.SingleTap += mapView_MapClick;

mapView.DoubleTap -= mapView_MapDoubleClick;
mapView.DoubleTap += mapView_MapDoubleClick;

However, the eventArgs SingleTapMapViewEventArgs,DoubleTapMapViewEventArgs does not have property, PointInWorldCoordinate anymore. How to retrieve this property in v14?

  1. ZoomMapTool
    In v13, we could hide the zoomMapTool by
    mapView.MapTools.ZoomMapTool.IsEnabled = false;

But in v14, mapView.MapTools.ZoomMapTool is no longer exist, how could I disable the zoomMapTool?

  1. ZoomLevelSet
    In v13, we could do
    var defaultMapScale = mapView.ZoomLevelSet.ZoomLevel12.Scale;
    but in v14, ZoomLevelSet is no longer exist, how could I do the same thing?

Thank you

#2

Hi Jimmy,

  1. In Maui, we use MapView.CenterPoint and MapView.MapScale for the extent, it’s better than CurrentExtent especially when RotationAngle is not 0.

  2. You can use the following line to convert screen coordinates to world coordinates:
    var pointInWorldCoordinate = MapView.ToWorldCoordinate(e.X, e.Y);

In fact let me write it down and we will discuss about it and may add PointInWorldCoordiante back.

  1. in Maui, you can add ZoomMapTool in xaml like following:

         <thinkgeo:MapView Grid.Row="1" x:Name="MapView" Grid.RowSpan="2" 
                       MapRotation="0" SizeChanged="MapView_OnSizeChanged">
         <thinkgeo:MapView.MapTools>
             <thinkgeo:ZoomMapTool />
         </thinkgeo:MapView.MapTools>
     </thinkgeo:MapView>

ZoomMapTool is a standalone Maui component, you can just set IsVisible to show/hide it.

  1. In Maui, zoomLevelSet on MapView is a bit confusing because you can stop the map at any scale, that’s why we removed it. Now we have TileOverlay.ZoomLevelSet, which identifies the zoomlevels of the tiles, is this something you can use? Let me know your scenario and we can give you a better suggestion.

Please play with the Maui HowDoI samples : ThinkGeo / Public / Mobile Maps · GitLab, where you can find lots of good sample codes.

Thanks,
Ben

#3

Thank you Ben.
Just got another question.
I am using XyzTileAsyncLayer in Xamarin app, but somehow in MAUI, the layer is not showing.

After some testing, it seems that Insert function is not working and have to use “Add” otherwise the map is not showing up. Am I missing something or it has a bug?

MapView.Overlays.Insert(0, layerOverlay);

Please find the attached sample.Xyz.xaml (683 Bytes) Xyz.xaml.cs (2.3 KB)

Another issue is the map is sometime not loading…It is loaded after moving the extent, but it will then behavior strange (cannot drag to move etc)
I can see the log as below

java.io.FileNotFoundException: open failed: ENOENT (No such file or directory)
[Glide] at android.os.ParcelFileDescriptor.openInternal(ParcelFileDescriptor.java:363)
[Glide] at android.os.ParcelFileDescriptor.open(ParcelFileDescriptor.java:239)
[Glide] at android.content.ContentResolver.openAssetFileDescriptor(ContentResolver.java:1853)
[Glide] at android.content.ContentResolver.openAssetFileDescriptor(ContentResolver.java:1773)
[Glide] at com.bumptech.glide.load.data.AssetFileDescriptorLocalUriFetcher.loadResource(AssetFileDescriptorLocalUriFetcher.java:20)
[Glide] at com.bumptech.glide.load.data.AssetFileDescriptorLocalUriFetcher.loadResource(AssetFileDescriptorLocalUriFetcher.java:11)
[Glide] at com.bumptech.glide.load.data.LocalUriFetcher.loadData(LocalUriFetcher.java:44)
[Glide] at com.bumptech.glide.load.model.MultiModelLoader$MultiFetcher.loadData(MultiModelLoader.java:100)
[Glide] at com.bumptech.glide.load.engine.SourceGenerator.startNextLoad(SourceGenerator.java:95)
[Glide] at com.bumptech.glide.load.engine.SourceGenerator.startNext(SourceGenerator.java:88)
[Glide] at com.bumptech.glide.load.engine.DecodeJob.runGenerators(DecodeJob.java:311)
[Glide] at com.bumptech.glide.load.engine.DecodeJob.onDataFetcherFailed(DecodeJob.java:416)
[Glide] at com.bumptech.glide.load.engine.SourceGenerator.onLoadFailedInternal(SourceGenerator.java:223)
[Glide] at com.bumptech.glide.load.engine.SourceGenerator$1.onLoadFailed(SourceGenerator.java:108)
[Glide] at com.bumptech.glide.load.model.MultiModelLoader$MultiFetcher.startNextOrFail(MultiModelLoader.java:167)
[Glide] at com.bumptech.glide.load.model.MultiModelLoader$MultiFetcher.onLoadFailed(MultiModelLoader.java:154)
[Glide] at com.bumptech.glide.load.data.LocalUriFetcher.loadData(LocalUriFetcher.java:50)
[Glide] at com.bumptech.glide.load.model.MultiModelLoader$MultiFetcher.loadData(MultiModelLoader.java:100)
[Glide] at com.bumptech.glide.load.engine.SourceGenerator.startNextLoad(SourceGenerator.java:95)
[Glide] at com.bumptech.glide.load.engine.SourceGenerator.startNext(SourceGenerator.java:88)
[Glide] at com.bumptech.glide.load.engine.DecodeJob.runGenerators(DecodeJob.java:311)
[Glide] at com.bumptech.glide.load.engine.DecodeJob.onDataFetcherFailed(DecodeJob.java:416)
[Glide] at com.bumptech.glide.load.engine.SourceGenerator.onLoadFailedInternal(SourceGenerator.java:223)
[Glide] at com.bumptech.glide.load.engine.SourceGenerator$1.onLoadFailed(SourceGenerator.java:108)
[Glide] at com.bumptech.glide.load.model.MultiModelLoader$MultiFetcher.startNextOrFail(MultiModelLoader.java:167)
[Glide] at com.bumptech.glide.load.model.MultiModelLoader$MultiFetcher.onLoadFailed(MultiModelLoader.java:154)
[Glide] at com.bumptech.glide.load.data.LocalUriFetcher.loadData(LocalUriFetcher.java:50)
[Glide] at com.bumptech.glide.load.model.MultiModelLoader$MultiFetcher.loadData(MultiModelLoader.java:100)
[Glide] at com.bumptech.glide.load.engine.SourceGenerator.startNextLoad(SourceGenerator.java:95)
[Glide] at com.bumptech.glide.load.engine.SourceGenerator.startNext(SourceGenerator.java:88)
[Glide] at com.bumptech.glide.load.engine.DecodeJob.runGenerators(DecodeJob.java:311)
[Glide] at com.bumptech.glide.load.engine.DecodeJob.runWrapped(DecodeJob.java:280)
[Glide] at com.bumptech.glide.load.engine.DecodeJob.run(DecodeJob.java:235)
[Glide] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
[Glide] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:644)
[Glide] at com.bumptech.glide.load.engine.executor.GlideExecutor$DefaultThreadFactory$1.run(GlideExecutor.java:424)
[Glide] at java.lang.Thread.run(Thread.java:1012)
[Glide] at com.bumptech.glide.load.engine.executor.GlideExecutor$DefaultPriorityThreadFactory$1.run(GlideExecutor.java:383)

I am using v14.2.1 with Android, not tested with iOS so far.

Thank you

#4

Hi Jimmy,

Thanks for letting us know!

  1. It is a bug that Overlays.Insert doesn’t work. The bug is fixed in 14.3.0-beta071 and later versions, please pull the latest and have another try. (The fix is not included in the latest release v14.2.2)
  2. I couldn’t recreate the map-is-sometime-not-loading-issue, can you pull the latest version and have another try? Here are some settings you can play with:
  • change the overlay.TileType to TileType.MultiTile (it’s singleTile by default), change the tileSize to 256 or 512(default)
  • Show the tile ID on the tiles: ThinkGeoDebugger.DisplayTileId = true;
  • Show more debug info in the Output window:
    ThinkGeoDebugger.LogLevel = ThinkGeoLogLevel.All;
    ThinkGeoDebugger.LogType = ThinkGeoLogType.Rendering;

Please let us know the model or your device/emulation if you still see issue #2.

Thanks,
Ben

#5

Thanks Ben,

It seems issue 2 is not happening in the latest beta version so far…
will keep an eye to see if it happens again.

By the way, may I know if there is any build in clustering feature in the library?
Thank you

#6

Yes, and we have a cluster sample in HowDoI -> Vector Data Styling -> Display Cluster Points

image
image624×1424 72.7 KB

1 Like
#7

Hi Ben,

I am working on the clustering and hope that I could get some ideas on the refresh map.
Currently my map view has 3 overlay

  1. Base overlay where store the map
  2. Marker overlay where store all the marker
  3. Drawing overlay where store all drawing from user

In Marker overlay, there are 3 layer

  1. For all PointStyle feature, that include cluster point
  2. For all AreaStyle feature
  3. For all LineStyle feature

I am now hitting Collection was modified error, probably causing by frequently updating the map.
My question is when should I update the map to reload the features? It has to reload since the cluster points will contains different numbers of children in different zoom level.

Below are the captured log when the error happens

[0:] ThinkGeo Message - 15:19:30.3868405: TileOverlay Draw Start
[0:] ThinkGeo Message - 15:19:30.4134965: TileView 68: 0-0-0 Draw Start
[0:] ThinkGeo Message - 15:19:30.4581910: Animation Start
[0:] ThinkGeo Message - 15:19:30.4966393: Tile 68: 0-0-0 SetImageAsync Start
[0:] ThinkGeo Message - 15:19:30.6082029: TileView 68: 0-0-0 Drawn End
[0:] ThinkGeo Message - 15:19:30.6407391: Single Tile Post Start
[0:] ThinkGeo Message - 15:19:30.6651089: TileView 68: 0-0-0 Post Start
[0:] ThinkGeo Message - 15:19:30.6936471: TileView 68: 0-0-0 Post End
[0:] ThinkGeo Message - 15:19:30.7262708: Animation Completed
[0:] ThinkGeo Message - 15:19:30.7750715: Draw Start
[0:] ThinkGeo Message - 15:19:30.8166265: TileOverlay Draw Start
[0:] ThinkGeo Message - 15:19:30.8305522: TileView 69: 0-0-0 Draw Start
[0:] ThinkGeo Message - 15:19:30.8879045: TileView 69: 0-0-0 Draw Canceled
[0:] ThinkGeo Message - 15:19:30.9180396: TileOverlay Draw Canceled
[0:] ThinkGeo Message - 15:19:30.9458411: Single Tile Post End
[0:] ThinkGeo Message - 15:19:30.9684162: TileOverlay Draw End
[0:] ThinkGeo Message - 15:19:30.9859835: TileOverlay Draw Start
[0:] ThinkGeo Message - 15:19:31.0044164: TileView 70: 0-0-0 Draw Start
[0:] ThinkGeo Message - 15:19:31.0333529: Draw Start
[0:] ThinkGeo Message - 15:19:31.0555145: TileOverlay Draw Start
[0:] ThinkGeo Message - 15:19:31.0779877: TileView 71: 0-0-0 Draw Start
[0:] ThinkGeo Message - 15:19:31.1486210: Tile 70: 0-0-0 SetImageAsync Start
[EGL_emulation] app_time_stats: avg=4.50ms min=1.23ms max=13.08ms count=31
System.InvalidOperationException: 'Collection was modified; enumeration operation may not execute.'v

[0:] ThinkGeo Message - 11:21:59.4341655: Animation Start
[tarn.android] Explicit concurrent mark compact GC freed 276KB AllocSpace bytes, 4(2256KB) LOS objects, 49% free, 13MB/27MB, paused 163us,2.797ms total 21.804ms
[0:] ThinkGeo Message - 11:21:59.6343927: Animation Completed
[0:] ThinkGeo Message - 11:21:59.6707048: Draw Start
[0:] ThinkGeo Message - 11:21:59.7026321: TileOverlay Draw Start
[0:] ThinkGeo Message - 11:21:59.7350229: TileView 18: 0-0-0 Draw Start
[0:] ThinkGeo Message - 11:21:59.7768920: Tile 18: 0-0-0 SetImageAsync Start
[0:] ThinkGeo Message - 11:21:59.8581408: TileView 18: 0-0-0 Drawn End
[0:] ThinkGeo Message - 11:21:59.8903703: Single Tile Post Start
[0:] ThinkGeo Message - 11:21:59.9270476: TileView 18: 0-0-0 Post Start
[0:] ThinkGeo Message - 11:21:59.9631924: TileView 18: 0-0-0 Post End
[0:] ThinkGeo Message - 11:22:00.0223977: Single Tile Post End
[EGL_emulation] app_time_stats: avg=17.23ms min=13.05ms max=36.00ms count=59
[0:] ThinkGeo Message - 11:22:00.0634218: TileOverlay Draw End
[0:] ThinkGeo Message - 11:22:00.1056683: TileOverlay Draw Start
[0:] ThinkGeo Message - 11:22:00.1454603: TileView 19: 0-0-0 Draw Start
[0:] ThinkGeo Message - 11:22:00.1851550: Tile 19: 0-0-0 SetImageAsync Start
[0:] ThinkGeo Message - 11:22:00.2817092: TileView 19: 0-0-0 Drawn End
[0:] ThinkGeo Message - 11:22:00.3260326: Single Tile Post Start
[0:] ThinkGeo Message - 11:22:00.3655159: TileView 19: 0-0-0 Post Start
[0:] ThinkGeo Message - 11:22:00.4077970: TileView 19: 0-0-0 Post End
[0:] ThinkGeo Message - 11:22:00.4686346: Single Tile Post End
[0:] ThinkGeo Message - 11:22:00.5169648: TileOverlay Draw End
[0:] ThinkGeo Message - 11:22:00.5593404: TileOverlay Draw Start
[0:] ThinkGeo Message - 11:22:00.6036609: TileView 20: 0-0-0 Draw Start
[0:] ThinkGeo Message - 11:22:00.9175623: Tile 20: 0-0-0 SetImageAsync Start
[EGL_emulation] app_time_stats: avg=16.97ms min=14.32ms max=36.59ms count=60
[0:] ThinkGeo Message - 11:22:01.0076016: TileView 16: 0-0-0 Post Timeout after 3000 ms
[0:] ThinkGeo Message - 11:22:01.1665241: Single Tile Post End
[0:] ThinkGeo Message - 11:22:01.2103720: TileOverlay Draw End
[0:] ThinkGeo Message - 11:22:01.2527594: TileOverlay Draw Start
[0:] ThinkGeo Message - 11:22:01.2912847: TileView 21: 0-0-0 Draw Start
[0:] ThinkGeo Message - 11:22:01.5792794: Tile 21: 0-0-0 SetImageAsync Start
[tarn.android] Explicit concurrent mark compact GC freed 816KB AllocSpace bytes, 67(9612KB) LOS objects, 49% free, 12MB/25MB, paused 172us,3.155ms total 27.988ms
[tarn.android] Explicit concurrent mark compact GC freed 108KB AllocSpace bytes, 0(0B) LOS objects, 49% free, 12MB/25MB, paused 144us,3.505ms total 21.346ms
[0:] ThinkGeo Message - 11:22:01.7845062: TileView 20: 0-0-0 Drawn End
[0:] ThinkGeo Message - 11:22:01.8235510: Single Tile Post Start
[0:] ThinkGeo Message - 11:22:01.8619871: TileView 20: 0-0-0 Post Start
[0:] ThinkGeo Message - 11:22:01.9054937: TileView 20: 0-0-0 Post End
[0:] Current location result lat=-37.8084 Lon=144.973505
[0:] Adding current location to user location layer
[0:] ThinkGeo Message - 11:22:02.0503605: TileOverlay Draw Start
[EGL_emulation] app_time_stats: avg=16.63ms min=13.62ms max=18.73ms count=61
[0:] ThinkGeo Message - 11:22:02.1050265: TileView 22: 0-0-0 Draw Start
[0:] Current location result lat=-37.8084 Lon=144.973505
[0:] Adding current location to user location layer
[0:] 0d031cc2-fdab-428f-be12-24a0446ede3d complete
[0:] ThinkGeo Message - 11:22:02.3363356: Single Tile Post End
[0:] ThinkGeo Message - 11:22:02.3759755: TileOverlay Draw End
[0:] ThinkGeo Message - 11:22:02.4226263: Draw End
[Choreographer] Skipped 35 frames! The application may be doing too much work on its main thread.
[tarn.android] Explicit concurrent mark compact GC freed 284KB AllocSpace bytes, 0(0B) LOS objects, 49% free, 12MB/25MB, paused 205us,5.089ms total 23.284ms
[0:] ThinkGeo Message - 11:22:02.5003530: TileView 21: 0-0-0 Drawn End
[0:] ThinkGeo Message - 11:22:02.5709452: Single Tile Post Start
[0:] ThinkGeo Message - 11:22:02.6107090: TileView 21: 0-0-0 Post Start
[0:] ThinkGeo Message - 11:22:02.6509705: TileView 21: 0-0-0 Post End
[tarn.android] Explicit concurrent mark compact GC freed 128KB AllocSpace bytes, 0(0B) LOS objects, 49% free, 12MB/25MB, paused 188us,2.653ms total 19.626ms
System.InvalidOperationException: ‘Collection was modified; enumeration operation may not execute.’

#8

Hi Jimmy,

It shouldn’t throw a ‘Collection was modified’ exception; it must be a bug.

Thanks for the log, but sorry I cannot determine the cause. Could you please send a demo project to us or share some code showing how you update the map? (You can either email it or create a ticket and upload it there if you prefer not to disclose it publicly). I’m wondering how you were updating the map, maybe keep updating the marker positions?

Thanks,
Ben

#9

Hi Jimmy,

Yes, the ThinkGeo library does use Microsoft.Data.Sqlite (which includes SQLitePCLRaw.bundle_e_sqlite3) in MAUI versions as well, you can decouple SQLitePCLRaw.bundle_e_sqlite3 and replace it with SQLitePCLRaw.bundle_e_sqlcipher just like you did in Xamarin.Forms.

Thanks,
Ben

#10

Hi Jimmy,

Yes, the ThinkGeo library does use Microsoft.Data.Sqlite (which includes SQLitePCLRaw.bundle_e_sqlite3) by default in MAUI as well, and you can decouple it and replace it with SQLitePCLRaw.bundle_e_sqlcipher just like you did in Xamarin.Forms.

Thanks,
Ben

#11

Hi Team,
my iOS app is crashing after update to 14.3 stable version.
It does not always happen, just occur if I switch from page A to page B quickly. And both pages have their own map

[0:] ThinkGeo Message - 22:57:16.7094190: Tile 11: 0-0-0 SetImageAsync Start
System.NullReferenceException: ‘Loading…’

Thread finished: #206
The thread 206 has exited with code 0 (0x0).
System.NullReferenceException: ‘Object reference not set to an instance of an object.’

2025-05-16 22:57:35.101671+1000 myapp[86274:4124106]
Unhandled Exception:
System.NullReferenceException: Object reference not set to an instance of an object.
at ThinkGeo.Core.MapUtil.GetScale(RectangleShape worldExtent, Double screenWidth, GeographyUnit worldExtentUnit, Single dpi)
at ThinkGeo.UI.Maui.EditInteractiveOverlay.TransformCore(RectangleShape extent, IMapView mapView)
at ThinkGeo.UI.Maui.Overlay.Transform(RectangleShape extent, IMapView mapView)
at ThinkGeo.UI.Maui.MapView.QEc=.R0c=(Double progress)
at Microsoft.Maui.Controls.Animation.<>c__DisplayClass2_0.<.ctor>b__0(Double f)
at Microsoft.Maui.Controls.Animation.b__5_0(Double f)
at Microsoft.Maui.Controls.Animation.b__5_0(Double f)
at Microsoft.Maui.Controls.AnimationExtensions.<>c__DisplayClass21_01[[System.Double, System.Private.CoreLib, Version=9.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].<AnimateInternal>b__0(Double f) at Microsoft.Maui.Controls.AnimationExtensions.HandleTweenerUpdated(Object o, EventArgs args) at Microsoft.Maui.Controls.Tweener.Step(Int64 step) at Microsoft.Maui.Controls.TweenerAnimation.OnTick(Double millisecondsSinceLastUpdate) at Microsoft.Maui.Animations.Animation.Tick(Double milliseconds) at Microsoft.Maui.Animations.AnimationManager.<>c__DisplayClass20_0.<OnFire>g__OnAnimationTick|0(Animation animation) at System.Collections.Generic.List1[[Microsoft.Maui.Animations.Animation, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]].ForEach(Action1 action) at Microsoft.Maui.Animations.AnimationManager.OnFire() at Microsoft.Maui.Animations.PlatformTicker.<Start>b__3_0() at Foundation.NSActionDispatcher.Apply() in /Users/builder/azdo/_work/7/s/macios/src/Foundation/NSAction.cs:line 64 --- End of stack trace from previous location --- at ObjCRuntime.Runtime.ThrowException(IntPtr gchandle) in /Users/builder/azdo/_work/7/s/macios/src/ObjCRuntime/Runtime.cs:line 2831 at UIKit.UIApplication.UIApplicationMain(Int32 argc, String[] argv, IntPtr principalClassName, IntPtr delegateClassName) in /Users/builder/azdo/_work/7/s/macios/src/UIKit/UIApplication.cs:line 75 at UIKit.UIApplication.Main(String[] args, Type principalClass, Type delegateClass) in /Users/builder/azdo/_work/7/s/macios/src/UIKit/UIApplication.cs:line 107 at myapp.Program.Main(String[] args) in C:\Users\Jimmy Pun\Desktop\Projects\myapp-MAUI\myapp\Platforms\iOS\Program.cs:line 13 2025-05-16 22:57:35.108232+1000 myapp[86274:4124106] Unhandled managed exception: Object reference not set to an instance of an object. (System.NullReferenceException) at ThinkGeo.Core.MapUtil.GetScale(RectangleShape worldExtent, Double screenWidth, GeographyUnit worldExtentUnit, Single dpi) at ThinkGeo.UI.Maui.EditInteractiveOverlay.TransformCore(RectangleShape extent, IMapView mapView) at ThinkGeo.UI.Maui.Overlay.Transform(RectangleShape extent, IMapView mapView) at ThinkGeo.UI.Maui.MapView.QEc=.R0c=(Double progress) at Microsoft.Maui.Controls.Animation.<>c__DisplayClass2_0.<.ctor>b__0(Double f) at Microsoft.Maui.Controls.Animation.<GetCallback>b__5_0(Double f) at Microsoft.Maui.Controls.Animation.<GetCallback>b__5_0(Double f) at Microsoft.Maui.Controls.AnimationExtensions.<>c__DisplayClass21_01[[System.Double, System.Private.CoreLib, Version=9.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].b__0(Double f)
at Microsoft.Maui.Controls.AnimationExtensions.HandleTweenerUpdated(Object o, EventArgs args)
at Microsoft.Maui.Controls.Tweener.Step(Int64 step)
at Microsoft.Maui.Controls.TweenerAnimation.OnTick(Double millisecondsSinceLastUpdate)
at Microsoft.Maui.Animations.Animation.Tick(Double milliseconds)
at Microsoft.Maui.Animations.AnimationManager.<>c__DisplayClass20_0.g__OnAnimationTick|0(Animation animation)
at System.Collections.Generic.List1[[Microsoft.Maui.Animations.Animation, Microsoft.Maui, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]].ForEach(Action1 action)
at Microsoft.Maui.Animations.AnimationManager.OnFire()
at Microsoft.Maui.Animations.PlatformTicker.b__3_0()
at Foundation.NSActionDispatcher.Apply() in /Users/builder/azdo/_work/7/s/macios/src/Foundation/NSAction.cs:line 64
— End of stack trace from previous location —
at ObjCRuntime.Runtime.ThrowException(IntPtr gchandle) in /Users/builder/azdo/_work/7/s/macios/src/ObjCRuntime/Runtime.cs:line 2831
at UIKit.UIApplication.UIApplicationMain(Int32 argc, String[] argv, IntPtr principalClassName, IntPtr delegateClassName) in /Users/builder/azdo/_work/7/s/macios/src/UIKit/UIApplication.cs:line 75
at UIKit.UIApplication.Main(String[] args, Type principalClass, Type delegateClass) in /Users/builder/azdo/_work/7/s/macios/src/UIKit/UIApplication.cs:line 107
at myapp.Program.Main(String[] args) in C:\Users\Jimmy Pun\Desktop\Projects\myapp-MAUI\myapp\Platforms\iOS\Program.cs:line 13

=================================================================
Native Crash Reporting

Got a SIGABRT while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.

=================================================================
Native stacktrace:

0x105dd291c - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/B2F371AA-F447-417C-98EA-6DC40EA69E67/myapp.app/libmonosgen-2.0.dylib : mono_dump_native_crash_info
0x105d7f6d8 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/B2F371AA-F447-417C-98EA-6DC40EA69E67/myapp.app/libmonosgen-2.0.dylib : mono_handle_native_crash
0x105f4b350 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/B2F371AA-F447-417C-98EA-6DC40EA69E67/myapp.app/libmonosgen-2.0.dylib : sigabrt_signal_handler.cold.1
0x105dd2200 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/B2F371AA-F447-417C-98EA-6DC40EA69E67/myapp.app/libmonosgen-2.0.dylib : mono_runtime_setup_stat_profiler
0x104b03640 - /usr/lib/system/libsystem_platform.dylib : _sigtramp
0x104f7a2ec - /usr/lib/system/libsystem_pthread.dylib : pthread_kill
0x1801704ec - /Library/Developer/CoreSimulator/Volumes/iOS_22D8075/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS 18.3.simruntime/Contents/Resources/RuntimeRoot/usr/lib/system/libsystem_c.dylib : abort
0x105a77558 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/B2F371AA-F447-417C-98EA-6DC40EA69E67/myapp.app/libxamarin-dotnet-debug.dylib : xamarin_find_protocol_wrapper_type
0x105e63724 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/B2F371AA-F447-417C-98EA-6DC40EA69E67/myapp.app/libmonosgen-2.0.dylib : mono_invoke_unhandled_exception_hook
0x105d42a68 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/B2F371AA-F447-417C-98EA-6DC40EA69E67/myapp.app/libmonosgen-2.0.dylib : mono_jit_exec
0x105a8ba6c - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/B2F371AA-F447-417C-98EA-6DC40EA69E67/myapp.app/libxamarin-dotnet-debug.dylib : xamarin_main
0x1043b4518 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/B2F371AA-F447-417C-98EA-6DC40EA69E67/myapp.app/myapp : main
0x104b31410 - Unknown
0x10486ab4c - Unknown

=================================================================
Basic Fault Address Reporting

Memory around native instruction pointer (0x1058b8874):0x1058b8864 c0 03 5f d6 c0 03 5f d6 10 29 80 d2 01 10 00 d4 ………)…
0x1058b8874 e3 00 00 54 fd 7b bf a9 fd 03 00 91 16 e3 ff 97 …T.{…
0x1058b8884 bf 03 00 91 fd 7b c1 a8 c0 03 5f d6 c0 03 5f d6 …{…….
0x1058b8894 70 0a 80 d2 01 10 00 d4 e3 00 00 54 fd 7b bf a9 p…T.{…

=================================================================
Managed Stacktrace:

=================================================================

#12

Hi Jimmy,

Thanks for the detailed log!

The issue occurs because when the MapView is disposed, the ongoing animations are not properly canceled, and still trying to access properties that have already become invalid. This returned an incorrect value before, but now in v14.3 it returns null, which triggers the crash you’re seeing.

We’ve addressed this in the latest beta by:

  1. Canceling the animation during MapView.Dispose() .
  2. Adding a null check inside Overlay.Transform .

Please pull the latest package ThinkGeo.UI.Maui 14.4.0-beta006 and have another try.

Thanks,
Ben

#13

Hi Ben,

Thank you for the quick response.
I have installed the 14.4.0-beta006 and tried again.
It seems the original bug is gone but there is another one come up.
It happens when I switch to page b, no matter how long i wait for
Below are the log

[0:] ThinkGeo Message - 09:28:36.0488940: Tile 10: 0-0-0 SetImageAsync Start
2025-05-19 09:28:36.068111+1000 myapp[94736:4407647]
Unhandled Exception:
System.NullReferenceException: Object reference not set to an instance of an object.
at ThinkGeo.Core.FeatureLayer.IsDrawingNeededCore(Double currentScale)
at ThinkGeo.Core.LayerBase.IsDrawingNeeded(Double currentScale)
at ThinkGeo.UI.Maui.LayerOverlay.Hz4=.nD8=(LayerBase layer)
at System.Linq.Enumerable.Any[LayerBase](IEnumerable1 source, Func2 predicate)
at ThinkGeo.UI.Maui.LayerOverlay.DrawAsyncCore(OverlayRefreshType refreshType, CancellationToken cancellationToken)
at ThinkGeo.UI.Maui.Overlay.DrawAsync(OverlayRefreshType refreshType, CancellationToken cancellationToken)
at ThinkGeo.UI.Maui.MapView.rEY=(OverlayRefreshType refreshType, Overlay overlay, CancellationToken cancellationToken)
at ThinkGeo.UI.Maui.MapView.W0I=(PointShape centerPoint, OverlayRefreshType refreshType, Boolean skipPost, OverlaysRenderSequenceType overlaysRenderSequenceType, CancellationToken cancellationToken)
at ThinkGeo.UI.Maui.MapView.v0Y=()
at Microsoft.Maui.Dispatching.DispatcherExtensions.<>c__DisplayClass3_0.<b__0>d.MoveNext()
— End of stack trace from previous location —
at Microsoft.Maui.Dispatching.DispatcherExtensions.<>c__DisplayClass2_01.<<DispatchAsync>b__0>d[[System.Boolean, System.Private.CoreLib, Version=9.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext() --- End of stack trace from previous location --- at ThinkGeo.UI.Maui.MapView.RkI=(Object sender, ElapsedEventArgs e) at System.Threading.Tasks.Task.<>c.<ThrowAsync>b__128_1(Object state) at System.Threading.QueueUserWorkItemCallbackDefaultContext.Execute() at System.Threading.ThreadPoolWorkQueue.DispatchItemWithAutoreleasePool(Object workItem, Thread currentThread) at System.Threading.ThreadPoolWorkQueue.Dispatch() at System.Threading.PortableThreadPool.WorkerThread.WorkerThreadStart() at System.Threading.Thread.StartCallback() 2025-05-19 09:28:36.073635+1000 myapp[94736:4407647] Unhandled managed exception: Object reference not set to an instance of an object. (System.NullReferenceException) at ThinkGeo.Core.FeatureLayer.IsDrawingNeededCore(Double currentScale) at ThinkGeo.Core.LayerBase.IsDrawingNeeded(Double currentScale) at ThinkGeo.UI.Maui.LayerOverlay.Hz4=.nD8=(LayerBase layer) at System.Linq.Enumerable.Any[LayerBase](IEnumerable1 source, Func2 predicate) at ThinkGeo.UI.Maui.LayerOverlay.DrawAsyncCore(OverlayRefreshType refreshType, CancellationToken cancellationToken) at ThinkGeo.UI.Maui.Overlay.DrawAsync(OverlayRefreshType refreshType, CancellationToken cancellationToken) at ThinkGeo.UI.Maui.MapView.rEY=(OverlayRefreshType refreshType, Overlay overlay, CancellationToken cancellationToken) at ThinkGeo.UI.Maui.MapView.W0I=(PointShape centerPoint, OverlayRefreshType refreshType, Boolean skipPost, OverlaysRenderSequenceType overlaysRenderSequenceType, CancellationToken cancellationToken) at ThinkGeo.UI.Maui.MapView.v0Y=() at Microsoft.Maui.Dispatching.DispatcherExtensions.<>c__DisplayClass3_0.<<DispatchAsync>b__0>d.MoveNext() --- End of stack trace from previous location --- at Microsoft.Maui.Dispatching.DispatcherExtensions.<>c__DisplayClass2_01.<b__0>d[[System.Boolean, System.Private.CoreLib, Version=9.0.0.0, Culture=neutral, PublicKeyToken=7cec85d7bea7798e]].MoveNext()
— End of stack trace from previous location —
at ThinkGeo.UI.Maui.MapView.RkI=(Object sender, ElapsedEventArgs e)
at System.Threading.Tasks.Task.<>c.b__128_1(Object state)
at System.Threading.QueueUserWorkItemCallbackDefaultContext.Execute()
at System.Threading.ThreadPoolWorkQueue.DispatchItemWithAutoreleasePool(Object workItem, Thread currentThread)
at System.Threading.ThreadPoolWorkQueue.Dispatch()
at System.Threading.PortableThreadPool.WorkerThread.WorkerThreadStart()
at System.Threading.Thread.StartCallback()

=================================================================
Native Crash Reporting

Got a SIGABRT while executing native code. This usually indicates
a fatal error in the mono runtime or one of the native libraries
used by your application.

=================================================================
Native stacktrace:

0x106a3691c - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/273D02B4-BF84-496A-BBEC-AB8806F59BEA/myapp.app/libmonosgen-2.0.dylib : mono_dump_native_crash_info
0x1069e36d8 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/273D02B4-BF84-496A-BBEC-AB8806F59BEA/myapp.app/libmonosgen-2.0.dylib : mono_handle_native_crash
0x106baf350 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/273D02B4-BF84-496A-BBEC-AB8806F59BEA/myapp.app/libmonosgen-2.0.dylib : sigabrt_signal_handler.cold.1
0x106a36200 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/273D02B4-BF84-496A-BBEC-AB8806F59BEA/myapp.app/libmonosgen-2.0.dylib : mono_runtime_setup_stat_profiler
0x105837640 - /usr/lib/system/libsystem_platform.dylib : _sigtramp
0x105f8a2ec - /usr/lib/system/libsystem_pthread.dylib : pthread_kill
0x1801704ec - /Library/Developer/CoreSimulator/Volumes/iOS_22D8075/Library/Developer/CoreSimulator/Profiles/Runtimes/iOS 18.3.simruntime/Contents/Resources/RuntimeRoot/usr/lib/system/libsystem_c.dylib : abort
0x1066db558 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/273D02B4-BF84-496A-BBEC-AB8806F59BEA/myapp.app/libxamarin-dotnet-debug.dylib : xamarin_find_protocol_wrapper_type
0x106ac7724 - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/273D02B4-BF84-496A-BBEC-AB8806F59BEA/myapp.app/libmonosgen-2.0.dylib : mono_invoke_unhandled_exception_hook
0x106b2b18c - /Users/jimmypun/Library/Developer/CoreSimulator/Devices/879C5EF5-2BE4-4A9B-AC50-D9EFDADA0CBC/data/Containers/Bundle/Application/273D02B4-BF84-496A-BBEC-AB8806F59BEA/myapp.app/libmonosgen-2.0.dylib : start_wrapper
0x105f8a5f0 - /usr/lib/system/libsystem_pthread.dylib : _pthread_start
0x105f85998 - /usr/lib/system/libsystem_pthread.dylib : thread_start

=================================================================
Basic Fault Address Reporting

Memory around native instruction pointer (0x106604874):0x106604864 c0 03 5f d6 c0 03 5f d6 10 29 80 d2 01 10 00 d4 ………)…
0x106604874 e3 00 00 54 fd 7b bf a9 fd 03 00 91 16 e3 ff 97 …T.{…
0x106604884 bf 03 00 91 fd 7b c1 a8 c0 03 5f d6 c0 03 5f d6 …{…….
0x106604894 70 0a 80 d2 01 10 00 d4 e3 00 00 54 fd 7b bf a9 p…T.{…

=================================================================
Managed Stacktrace:

=================================================================

#14

Just tried to twist my source code and it seems working now.
The problem is triggered by the IsVisible property of the view (or its parent).
If it is binding to a bool value with default false and load the map, it will create a lot of problem.
But if you set it to true by default and change it to false in code behind, it looks working fine.
Sounds like it is some mixed error with MAUI

#15

Hi Jimmy,

The exception should only be thrown when every zoomlevel in the zoomLevelSet is set to inactive(IsActive == false). I don’t know why it happened when using binding but we added more null check in the latest beta (v14.4.0 - beta006) so it should be working fine even with your original code. Please pull and have another try, and again thanks for your detailed log!

Thanks,
Ben

#16

Hi Team,

Just curious if the map has below features and created following questions

  1. Detecting MapScaleChanging, what I am trying to do is limiting the user zoom level because my tile does not support all zoom level, so I would like to limit the user zooming, I found that there is CurrentScaleChanging event but I guess it is referring to Scale property?

  2. Is there a default double tapped event? I have added my custom event
    mapView.DoubleTap += MapView_DoubleTap;
    It will zoom the user the tapped location with certain zoom level, however, it seems the map has it’s own zooming feature internally. The map will become zooming for 2 times. Not really sure where is the first time zooming fired and my event is always the second time zooming.

Thank you

#17

Hi Jimmy,

Here’s a clearer breakdown of how to handle each:

1. Limiting the user’s zoom level

a. Use MinScale and MaxScale

mapView.MinScale = 10_000;      // cannot zoom in closer than 1:10 000
mapView.MaxScale = 10_000_000;  // cannot zoom out beyond 1:10 000 000

b. Handle CurrentExtentChanging

mapView.CurrentExtentChanging += OnCurrentExtentChanging;

private void OnCurrentExtentChanging(object sender, CurrentExtentChangingMapViewEventArgs e)
{
    // e.IsMapScaleChanging is true if the zoom is changing
    if (e.IsMapScaleChanging)
    {
        // e.Cancel = true;  // uncomment to block the zoom change
    }
}

Note: We should have deprecated the older CurrentScaleChanging/CurrentScaleChanged events because “scale” often adjusts alongside center and rotation (e.g. pinch-stretch gestures). Canceling only the scale (set e.IsCanceled in the CurrentScaleChanging event) led to confusing states. We’ll mark them obsolete to avoid further confusion.

2. Controlling double-tap zoom

The map has a built-in double-tap zoom. If you want full control, you can either disable it or override it:

a. Disable the built-in double-tap

mapView.EventView.DoubleTapMode = MapDoubleTapMode.Disabled;

b. Subclass EventView and override DoubleTapCore

mapView.EventView = new MyEventView();

class MyEventView : EventView
{
    protected override TransformArguments DoubleTapCore(DoubleTapMapViewEventArgs e, IMapView mapView)
    {
        // Build your own zoom/center logic here
        return new TransformArguments();     
    }
}

That way, your handler is the only double-tap behavior.

Thanks,
Ben

1 Like
#18

Thanks Ben.

If we would like to change from RasterTileLayer to VectorTileLayer, is ThinkGeo support pbf file for the vector tile?

#19

Hi Jimmy,

Yes – ThinkGeo supports PBF‑encoded vector tiles via our MvtTilesAsyncLayer , which is available in the latest beta and will ship in v14.3.2 (be releasing by early next week). Here’s how it works:

  1. StyleJson‑driven
    You point MvtTilesAsyncLayer at a StyleJson file that defines both your styling rules and the PBF tile endpoint. The layer will fetch and render standard Mapbox Vector Tiles without any extra conversion.

  2. Sample code & demo
    We’ve included a working example in the WPF “HowDoI”, using JSON from the MapLibre demotiles repo. (Screenshot below for reference.) We’re planning to add the same demo to .NET MAUI samples after v14.3.2 release.

image
image1933×1063 413 KB

  1. Ongoing improvements
    We’re rolling out richer MVT support (performance tweaks, feature filtering, improved styling) in v14.4. It’s a great time to switch over—just let us know if you hit any snags. We are trying to enrich the pbf/mvt support and polish any rough edges.

Hope that helps!
Ben

1 Like