iGIS 8.3.0 Changes

iGIS 8.3.0 lays the groundwork for some potentially revolutionary features for iGIS. We’ve changed the format of data stored in iGIS to allow people to share and merge changes between different devices. This allows for some nifty collaboration that we hope our Pro users will appreciate.  If users like these sharing features, they may be expanded in the future with support for more cloud platforms ( such as Google Drive, OneDrive, etc.) and deeper integration with these services. Please let us know if you have any suggestions or concerns via email.

The major changes in iGIS 8.3.0 are:

  • Implemented the ability to share and merge changes on the same layers between multiple devices. For an in-depth explanation of how this works, please read our guide.
  • Added a “Tips” screen that shows off the latest features of iGIS when a user updates. Pro users may turn this off.
  • Provided a link on the main screen to some basic app settings.
  • Updated the Dropbox API to v2.
  • Some users had noticed the size of their database was not decreasing when they deleted layers. There is now an option to clean out the database on startup.
  • Removed all references to the email newsletter.
  • Some UI changes to make the interface more appealing.
  • Bug fixes and stability improvements.

Sharing Features in iGIS

iGIS 8.3.0 lays the foundation for potentially revolutionary sharing and collaboration features. To see the full list of changes, please read our change log

With iGIS 8.3.0, multiple users are now able to work on the same spatial layers separately and merge the differences. This guide explains how these sharing features work and their limitations.

To explain how sharing works, the example of three people working on the same data will be used.

Untitled Diagram (1)

John is a wildlife park ranger and he wants Sandra and Phil to draw the shapes of buildings in the park. He gives a copy of his data to Sandra and Phil. He has four shapes of the buildings already in his map layer. These are depicted as white rectangles to the right of his blue document icon and they have unique IDs that will come in handy later. Sandra and Phil have exactly the same data as John at this time. All of them have the latest version of iGIS.

Phil goes off to the north of the park and adds some building locations. He realises that John made a mistake on the second record, so he deletes it. iGIS actually doesn’t remove the feature from the database, it only marks it as deleted and no longer draws it on the map.

iGIS_MERGE_2

Sandra goes south and finds a couple of buildings so she adds them to the map. She discovers that incompetent John had made another mistake. She edits the fourth record. Notice the way the IDs are generated. If Sandra had the same username as Phil, iGIS would think that the features were the same!

iGIS_MERGE_3

Sandra and Phil return from their expeditions. Phil wants to get the changes that Sandra made. She exports her data the same way she always does in iGIS and gives a copy of the zip file to Phil.

Phil imports Sandra’s zip file using iGIS. iGIS realises that the data being imported is in the sharing format and that it has the same name as data already on his device. It offers Phil the option to merge the new data with his existing data.

Screen Shot 2017-01-12 at 3.24.08 pm

Phil decides to merge Sandra’s data onto his device. iGIS immediately imports every new item that Sandra added. New items will have unique IDs so it is very important that everyone using iGIS chooses a different username than the people they are sharing with. This username can be changed in Settings.

iGIS also keeps track of when the most recent edit was made. To decide which version of the same feature it has to keep, iGIS will always keep the most recent change. If a feature has no changes, iGIS will skip it.

Sandra’s version of John004 was more recently updated than Phil’s, so it replaces Phil’s copy. Phil’s deletion of John002 was more recent than Sandra’s copy, so it is kept.

If Sandra edited Phil’s deleted copy of John002 after he deleted it, it would have been merged in with his data and would be shown on the map again with Sandra’s edit.

After the merge, Phil’s data will look like it is below (with changes and deletions highlighted).

iGIS_MERGE_2 (1)

 

Phil now has a complete copy of all the data. He can give this to Sandra and John and they will get identical data by either overriding their copies or merging.

 

Note: this explanation simplifies some aspects of the sharing process, such as the length of the IDs. 

iGIS 8.2.0 changes

This update of iGIS contains bug fixes as well as some new features. These include:

This update is not yet on the App Store and will be there shortly (as of 27-6-16)

Width and Colour Attributes of Polygon Outlines

As of iGIS 8.2.0, there is now an option to set the width of a polygon’s outline. There is also a method to set a colour attribute; similar to how a polygon’s fill colour can be assigned an attribute. This post will explain how to do both.

Outline Width

To set the outline width, go to project settings and select the layer you wish to edit. It must be a polygon layer. Scroll down and select “Style/Color”. You will now see a slider for the “Outline Width”. Sliding this will control how thick the polygon’s outline appears on the map. Note: the outline width on the style sample boxes will not change. 

OutlineWidthSlider

Outline Colour Attributes

Go into project settings and navigate to the polygon layer you wish to edit. Now if you select the “Color Attributes”, there are two sections in the table. The first one is the Fill Colour Attribute and the second is the Outline Colour Attribute. To select an outline attribute, scroll down until you get to the outline section and select the attribute you wish to use to colour the outlines of your polygons.

Screen Shot 2016-06-27 at 12.27.39 PM

Label Colour

As of iGIS 8.2.0, you can now choose a colour for a layer’s labels. This makes it easier to know which labels belong to a layer, especially if there are many layers on screen. To choose your label colour, go into project settings, select a layer and scroll down until you get to “Label Color”

LabelColourAndAttrib

Selecting this will bring you to the colour sliders:

Screen Shot 2016-06-27 at 12.01.37 PM

By default, Auto Colour is on. Auto Colour changes between white and black labels depending on the map type (satellite, hybrid, map, etc.). You must switch this off if you want a custom label colour.

Scale Dependant Rendering

As of iGIS 8.2.0, there is now a new way zoom scaling is handled for layers. These changes can be used to dramatically improve performance in your project. For example, you might display low detailed polygons when zoomed out and switch to a highly detailed layer when zooming into the map.

To see the new changes, go into project settings and select a layer. Scrolling down, you should now see two sliders:

AppearsAtDisappearsAtSliders

The “Appears At” slider controls the maximum zoom a layer is visible at. The “Disappears At” slider controls the minimum zoom a layer is visible at. In the screenshot above, the BuildingsPolygon layer will be shown from a state level to 150m. If the user zooms in closer than 150m or zooms out further than the state level, the layer will disappear.

Make a Field Mandatory

From iGIS 8.2.0 onwards, there is now an ability to make feature attribute fields mandatory. This is done via a layer’s .glc file. Here is an example of a working .glc with mandatory fields:

example_glc.zip

The mandatory parameter is passed in the header of an attribute or codelist. In other words, an attribute header that is mandatory will look something like this:

<Attribute column=”asset_id” readable-name=”Asset_ID” mandatory=”YES”>

and a codelist that is mandatory looks something like this:

<CodeList name=”TrueFalseCodes” type=”C” length=”1″ mandatory=”true”>

Notice how it doesn’t matter if you pass “YES” or “true”, iGIS will interpret it as mandatory. In fact, you can use YES, yes, TRUE, true,  1, y or Y to set mandatory.

If there is no mandatory parameter passed, the default is NO. 

If you like, you may explicitly set mandatory to NO, no, false, FALSE, n, N or 0 to ensure the attribute or codelist is not mandatory.

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.

 

 

Retrieving data from iGIS

If you need to recover the data stored in iGIS you can retrieve it from your iPhone or iPad.

iGIS uses two sqlite databases; spatial-store.sqlite and Projects.sqlite. If you retrieve these files they can be used as a permanent backup or sent to Geometry for fault finding purposes.

Get these database files off your device using third party software like iFunBox  http://www.i-funbox.com/en_download.html

Using iFunBox, with your iPhone/iPad connected to your computer, open iTunes File Sharing:

Select iGIS (or iGIS HD) and select Open Sandbox

iFunBox2

Select the .database directory and copy both the Projects.sqlite and spatial-store.sqlite to your PC

iFunBox3

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