All posts by Jessica Clarke

How do I create a .zip file?

iGIS currently uses .zip files to import and export data.

A zip file  is a compressed folder that saves on space, allowing faster transfers. A zip can be created naturally on modern desktop operating system.  Usually this is done by selecting the items you want to zip, right clicking on them and selecting the option along the lines of “compress” or “send to>compressed (zipped) folder”.

 

For iGIS to use spatial data, the .dbf, .shp and .shx must not be contained in a subfolder within the zip.

Clashing .glc files?

If you have had trouble with your projects using the wrong .glc files, it may be because you have CodeLists that are repeated across multiple .glc files.

It is necessary to ensure all names in the CodeList are unique.

For example, if you have two projects with unique .glc files, that contain the ‘same’ CodeLists (with unique values).

In this case, the .glc will associate with the wrong projects.

To remedy, provide each CodeList name with a unique identifier.

 

 

FAQ – I can’t import my shapefile. ‘Shapefile loading error: near …’

There was an error loading shapefile:
Shapefile loading error: near “-“:
Syntax error

iGIS does not recognise special characters in file names or column headings in the .dbf.
In this example, the import is erroring on the hyphen (-) in either the title of the file, or the column headings in the dbf.
By removing the hyphen, and using an underscore (_) instead, you can avoid this error and load your shapefile successfully.

 

Deleting the Cache manually (updated)

UPDATE: There is now a way to limit the image cache size. Go to iOS Settings>iGIS>Map Display and specify the number of tiles the application will cache.

In order to maintain high performance when panning around your map, iGIS creates a cache of the maptiles.

This cache grows over time, and while it is limited to 1000 maptiles (it will probably only ever reach 450MB), you may find that you need to regain some of that space for various reasons.

Currently, we do not have a feature within the app itself to clear the cache, however, you can do this manually by using the iExplore software.

Please follow these instructions in order to clear the cache.

Download iExplorer http://www.macroplant.com/iexplorer/ (or similar)

  1. Using iExplore, with your iPhone/iPad connected to your computer, navigate to: <*Your Device Name*>\Apps\iGIS\Library\Caches
iExplorer_and_Airmail
Directory Structure

2.  Delete the RMTileCache.db file

3.  Disconnect your device

4.  Run the application – the RMTileCache.db file will be recreated, and will gradually increase as you use iGIS.  You may need to repeat these steps again.

Import from Email – iGIS 7 onwards

To import from email, follow the steps below.

1.  Open the email and tap on the zip file to load it.

Tap_to_load_png

2.  Select the ‘open in’ button as shown in the image below.

tap_to_open

3.  Select the iGIS application to import the data straight to iGIS.  You will be taken straight to the import page where you can then select the projection of your data and import it.

tap_to_import_igis

 


Convert 3D shapes to 2D for use with iGIS in iGIS 7.3

Have you encountered the following  error message while importing data?

Shapefile loading error:
Incompatible shapefile data structure
(iGIS does not support 3D data points)

At this stage, iGIS is unable to handle 3D shapefiles correctly, and your shapefiles will need to be edited to remove the z-value.

In the following example, ArcGIS will be used to convert convert 3D shapes to 2D shapes by using the Feature Class to Feature Class tool. It is possible to also use other GIS applications, such as QGIS.

1.  To locate the tool most easily,  just search for ‘feature class to feature class’.  Select the tool that is highlighted in the image below.

Search for Feature class to Feature class tool

2.   Select the shapefile that contains the 3D features, and load it into the ‘Input Features’ dropdown box.  Enter the ‘save’ location for the new shapefile.

3.  Select the ‘Environments…’ button to access the ‘Z Values’ settings.  This is where you will disable the z-value of your shapefile to create a 2D shape (see the two images following).  Repeat for ‘M Values‘.

Select the environments button
Select ‘DISABLED’ from the Z values section

4.  Click ‘OK’ and you are ready to load your new 2D shapefile into iGIS.

As always, we are happy to assist if you have any concerns or questions regarding this process.  Just email iphone@geometryit.com

 

— extra info http://forums.arcgis.com/threads/77695-w

iCloud Backup

iCloud is utilised by iGIS to store data and subscriptions, if the user allows it.
This short article will outline the pre-requisite settings to take advantage of these features.

If you are in the field, your data will only be saved on the device until you reach Wifi. There is an option to allow iCloud update via your mobile telephone network, should you require that.

1. Go to your iOS Device’s settings, and select iCloud

1. iCloud Settings Menu
1. iCloud Settings Menu

 

 

 

 

 

 

 

 

2. Access the ‘Storage and Backup’ menu at the bottom of the page.

2. Storage Menu
2. Storage Menu

3. a) Ensure that iCloud backup is switched ‘On’ as shown in the image below.  b) Select Manage Storage to select the iGIS application and turn backup ‘On’.

3. Manage Storage options and Backup
3a. Manage Storage options and Backup4. iGIS application found under 'BACKUP OPTIONS' (not shown)3b. iGIS application found under ‘BACKUP OPTIONS’ (not shown)

4. go ‘Back’ and perform a backup while connected to USB power.  The first backup may take a long time. You may want to do this overnight. (Note: you will need to be connected to a Wifi network.

Your device is now set up to allow for subscriptions to be shared, and data to be saved remotely to prevent data loss.

 

Custom data entry forms

The following article will document the process for generating and editing custom .glc files in order to create custom data entry forms in iGIS.

You can import: a .glc with your shapefile; and export it from iGIS.

dataEntryGlcFile

To start using customized forms, we recommend that you follow the following steps:

  • Step 1. Download the below linked sample glc shapefile data and become familiar with the format by; investigating the file in a text editor, importing it into iGIS, editing the shapefile in iGIS.
  • Step 2. Export your shapefile layer from iGIS to automatically create the *.glc.
  • Step 3. Edit your iGIS created *.glc template file with a text editor to add lookup code lists. Use the sample *.glc file from step 1 as a syntax reference.
  • Step 4. Import your shapefile into iGIS with your *.glc file, and begin editing your data with codelists.

Sample Form

We’ve produced a sample .glc file which is available here; FieldPoints3.zip

Use these samples to create your own customized forms. The sample data entry form is:

Projections issues

Some users have reported discrepancies with the location of their data over the basemap imagery in iGIS and/or a desktop GIS tool (such as ArcMap). If you are noticing a shift in your layers, this article may help you.

All vector data in iGIS is stored in the common coordinate system: WGS84 EPSG:4326. All raster data in iGIS (pre-processed through MapTiler software) is stored in the common coordinate system: EPSG:900913. Using these coordinate systems for all source data speeds up rendering in iGIS’s map display.

iGIS uses the open source proj4 library ( http://trac.osgeo.org/proj/ ) to support:

  • the reprojection of vector data on import/export from its original defined input coordinate system to WGS 84 (EPSG:4326)
  • re-projection of displayed iGIS project map centre coordinates from the WGS84 coordinate system into the projection defined for a particular project.

If you are unsure which coordinate system to use when you create a new project, we recommend you use the default EPSG:4326 WGS84 Lat/Lon for vector data.  This will ensure your data collection is not affected by reprojection within the application.

If you find that your points don’t line up with your basemap imagery as expected, it is likely that there is a bug with the proj4 library.  Bugs in the library can be submitted at the Proj4 website http://trac.osgeo.org/proj/ We incrementally update iGIS’s version of the Proj4 library with the latest available version, so when a fix becomes available in the library it will make its way into iGIS. Until then, the only workaround is to transform your data into a supported coordinate system, i.e. EPSG 4326 – WGS 84, with third party software like ArcGIS, prior to iGIS import.