In this post, we will use Input app to record tracks. The first step is to set up a project in QGIS.
In this tutorial we are going to set up a new survey project with more advanced features:
To start with, you will need to install the following software applications:
In addition, you will need to register with the Mergin service. The Mergin service allows you to transfer data between your PC/laptop and mobile/table via the cloud. Note that after signing up to the Mergin service, you have to activate the account by clicking on the link sent to your email.
Similar to the previous tutorial, we are going to start with a blank QGIS project. All the data and the project will be stored locally on a folder called recording tracks.
First, start a QGIS project and add the OpenStreetMap layer under XYZ Tiles. You can add also add aerial imagery as an XYZ layer to your QGIS.
Save your project as tracks in the recording tracks folder.
In addition, we need to create a Geopackage survey layer. Below are the attribute columns for your survey layer. Also note that need to select Line as geometry type.
To create a survey layer, in QGIS, from the main menu select Layer > Create Layer > New Geopackage Layer …. A new window will appear:
For Database click on … and select the recording tracks folder then type survey.gpkg for the name of your database.
For Table name, type tracks.
For Geometry type, select Line.
You can select the option to Include Z dimension. The upcoming version of Input app supports capturing altitude from your device (or external GPS device tethered with your phone/tablet).
For Coordinate Reference System (CRS), select WGS 84 / Pseudo-Mercator EPSG:3857.
Add the following Fields. Note, different field types:
Click OK to create and add the layer to your QGIS session.
We are going to style the tracks layer based on Type field and use four categories:
In the Layer Panels right-click on tracks layer and select Properties. A new window will appear. From the left panel, select Symbology. Change the styling from Single to Categorized on the top left section of the window. For the Value, select Type from the drop-down menu.
In the bottom-left section of the window, click on Classify. Then add 4 classes (by adding the green plus adjacent to Classify) for track types. In addition, we can add another class for Other types. Adjust the colours and line style accordingly:
To set up the form, select Attribute forms from the left panel of the layer properties window. Adjust the Widget type as below:
Input app allows you to have a custom pop-up drawer window when you tap on feature. To customise that, you can change the Display settings under the layer properties window. For Display name select Type and in the HTML Map Tip section type:
file:///[%@project_folder%]/[% "Photo" %]
We can set up two different map themes: one with aerial imagery and one with street map. To do that, ensure you have only the following layers are set to visible in your layer panel:
On top of the layers panel, select Manage Map Themes > Add Theme …
A new window will appear. Type Aerial photo for the name of your map theme and press OK.
Now, turn off your Aerial images layer in the layer panel and turn on the OpenStreetMap layer:
You can now add a new map theme and call it Street map.
If you missed a step, you can see the final version of the project here. You can also skip the above section by cloning the project in the above link.
In Input app, download and open Tracks project.
You can easily change between different map themes in Input, by going to (… More) > Map Themes:
To capture tracks, press Record button in the lower panel in Input. A green cross will appear, centred on your GPS location. You can capture a line in two different methods:
You can change the frequency of adding points when streaming GPS location, under Settings in Input. Also note that the GPS streaming can be done for polygon survey layer.
Once you finished capturing the track, press Done and you will be presented with a form:
You can easily fill the form using the drop-down menu for Type and checkbox option for Public.
By tapping on tracks on the map, you will should be able to see a small preview window presenting Type and Photo:
After completion of the survey, you can synchronise your data back through the Mergin and see the results in QGIS desktop.