Latest Contributions by wangzhifang

If you find your scale dependent layer does not work as you set in Client api, most likely the data source of your map service�?featureclass�?does not have correct spatial reference. Check the spatial reference of you data source first. ... View more

Actually, you could draw a circle by directly using the Draw class in Silverlight API. If you choose to draw it your self, and if you want the circle to change with the zoom in/out of the Map, you should draw it in map coordinate system; if you want the circle to remain the same size, no matter if the map's zoom in/out, you should draw it in screen coordinate and add it to an ElementLayer. Ref: http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#ElementLayer ... View more

Ah that means you only need to tweak the SDK sample a little bit. I've had this sample for awhile, kindly see attached. The client app will not have any layer visible sub layer until the checkbox is clicked. Hi Jennifer, you must misunderstood what I try to say originally. What I suggested is to use a sublayer(LayerInfo)'s property in binding to control its visibility, but without any code behind. Just don't know if it's worth to do it in API level. Anyway, I've learned your example and really appreciate your project. ... View more

Always double check your graphic�??s attributes. If there is something wrong, such as format doesn't match on serverside, SaveEdits() will do nothing. ... View more

I'm not sure I understand, you want the client app to update visibility on the server? If yes, I think this is a request you may want to post in the ArcGIS Server team. In the SubLayerList sample, you need not make every sub layer show by default. ArcGISDynamicMapServiceLayer.VisibleLayers can be an empty int[] {} that can be updated everytime a checkbox has been checked. Hi jennifer, what I mean is not to update the state of the map service on the server, but just control the exact sublayer's visibility on client side. I guess because of the exportmap operation of the REST sdk, so the behavior to control a sublayer's visibility is due to control of an int array of visible layers. But this is not convenient for binding. If there is additional Visibility dependencypropery on LayerInfo class, we could just control a sublayer's visibility by directly binding a checkbox on UI, rather than writing additional code in .cs file. Maybe in the setter of Visibility denpendencyproperty, construct a new array of visible layers and refresh the Layer is ok. Just a suggestion, don't know if it's worth to do this. 🙂 ... View more

I understand that the newest version fixes bugs and normally I would agree with you to upgrade. However, our client isn't going to allow us to change something so fundamental to the application without regression testing and we don't have time for regression testing. That's why we wanted to make a minimal impact and would prefer to be able to still get the installer for the current version that we're already working with. Sometime we will upgrade but now is (hopefully) not that time. You could download the version 2.1 api here: http://support.esrichina-bj.cn/2010/0917/630.html ... View more

Hi, ArcGISDynamicMapServiceLayer actually means a dynamic(not cached) map service published by ArcGIS Server, which is in REST format. So, to render you own data in silverlight app, all you need to do is to prepare your own ArcGISDynamicMapServiceLayer, which can be done by publishing your data by using ArcGIS Server. TODO list: 1. Prepare your data in arcmap and save them in a mxd file. 2. Using ArcGIS Server to publish the .mxd file as a map service. 3. Got the REST url of your map service. 4. Set the url to ArcGISDynamicMapServiceLayer. However, there have some details you may should know, such as difference between .mxd and .msd file, set resource read permissions to ArcGISSOC account, etc. All of these can be found here: http://help.arcgis.com/en/arcgisserver/10.0/help/arcgis_server_dotnet_help/index.html#/Preparing_resources_for_publishing_as_services/00930000005v000000/ ... View more

You should always upgrade to new version api on the time of its release. Because new version api does not only provide new functionalities, but also fix all the bugs have been reported. Although from version 1.2 to version 2.0, there do is a difference( server side requires 10.0 instead of previous), if you could use version 2.0 api, then you should upgrade to 2.2 final. ... View more

This can be done easily by client side. Just use dist=Math.Square(a*a+b*b) to calculate every distance between your point and each point on the polyline, then you get the nearest point on the polyline. ... View more

Hi, I'm trying to load an image (from local disk) onto a specific location on the map, some sort like placing a geotag image onto a map. I have defined my own layer, inherited from DynamicLayer and tried to override the GetSource method. My bitmap image is able to load, but my question is how do I set / calculate the extent, width and height ( as per GetSource parameters) such that the image extent and size changes proportionaly in size when zoom in / out? thanks! You don't need to do this by yourself. All you need is just an ElementLayer which is ready for use in Silverlight API:) http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#ElementLayer Or you can use MapTip to show your picture on a specific mappoint. http://help.arcgis.com/en/webapi/silverlight/samples/start.htm#GraphicsMapTip ... View more

Hey Zhifang, thanks very much! Actually I am using Silverlight API. I checked the sample and also modified my codes. It is so amazing 😄 I think the cluster method is pretty useful for street layer, zipcode point layer or similar things, especially when the spatial query should return a large number of results which need to be displayed on the graphicslayer later. In my codes, since I need to display the streets, I change the 'MediumMarkerSymbol' to 'MediumLineSymbol' <esri:SimpleLineSymbol x:Key="MediumLineSymbol" Color="Red" Width="4" /> I didn't change the FlareCluster part which I think is so cool 😛 But since the query results will be displayed on a datagrid and now the datagrid can only display 1000 results (and the graphicslayer only shows these 1000 results), if I want to display more than 1000 results, I must modify the service configuration file as you suggested, right? And since I am using the graphics cluster method, modifying the service configuration file won't slow down the performance right? Yes, to return more than 1,000 records while query from server, you need to modify the service configuration file(or change the number on Parameters tab on service properties dialog). However, you should be aware that the more records server returns, the more travel time of the data returns from server. In additaion, cluster is used when graphics are displayed by marker symbols. If you use cluster in line symbols or fill symbols, it may not make any sense. ... View more

Hey Zhifang, thank you for the advice. I can see that adding 1000 results is already slow the performance. So based on your advice I am thinking to use the graphicscluster to display the query results (I mean more than 1000). Could you share some sample codes or some clues on how to implement this? I really don't know how to do step the first step...Thank you very much! If you use ArcGIS API for Javascriipt, I'm sorry that you could not use a out-of-box cluster solution. For Flex API and Silverlight API, you can check the cluster example here and here. If you really need to display large amounts of data in Javascript API, consider using ArcGISDynamicMapServiceLayer which render them on server side. In addition, FYI: http://www.arcgis.com/home/item.html?id=5e32a79350b241f38032f9ca0321ccde ... View more

ArcGIS Server 10 returns max 1000 records while querying, ArcGIS Server 9.3.1 and pre version returns 500. This can be changed by modifying the service configuration file which is under <arcgis server install folder>/server/user directory. Change the <MaxRecordCount> tag, then restart your service. Also can be done in Parameters tab in service properties dialog in AGS 10. One thing you should pay attention to is that graphicslayer will get really stuck when adding more than about 2000 graphics in it. you should always use graphics cluster to display. ... View more