Documentation

# Further Project Customisation

In this tutorial you will learn how to customise your Mergin Maps project further, making it even more useful. The topics covered here are:

TIP

Previous tutorials already covered the minimum concepts for data collection so feel free to skip ahead to the Working Collaboratively tutorial (and come back here later on) if you're super keen on collecting data right away.

# Opening the project in QGIS

The various changes we will make to the project will be made in QGIS and their effect observed / tested in Mergin Maps Input.

If you already have the trees-and-hedges project open in QGIS, skip to Layer styles.

  1. Open QGIS

  2. Expand the Mergin entry in the Browser panel to show My projects:

  3. Expand My projects and locate the trees-and-hedges project

  4. Right-click it and select Open QGIS project:

The project should now be loaded in QGIS. Don't worry if you cannot see the features you surveyed in the field - this is probably because you've not yet synchronised the project in QGIS.

# Layer styles

When using Mergin Maps Input in the field in the last tutorial, we noticed hedges were difficult to see against the background maps (left image). We'll now fix that so they look more like the right image.

  1. Double-click the hedges layer in QGIS:

    Its layer properties dialog should appear.

  2. Select the Symbology tab on the left hand side

  3. Click the current colour to change it:

  4. Pick a new colour for hedges which stands out better

  5. Click OK

  6. Increase the line width to 0.46mm and click OK

Lines in the hedges layer should now be drawn thicker and in a more prominent colour. In the next section we'll see what these changes look like in Mergin Maps Input.

# Trialing changes in Mergin Maps Input

Seeing what the project changes we make in this tutorial look like in Mergin Maps Input is easy:

  1. In QGIS, save your project:

  2. Use the Synchronise Mergin Project tool:

    QGIS and your project in the cloud should now be synchronised.

  3. Open Mergin Maps Input on your mobile device

  4. Open the Home tab of the Projects page

    You should see a sync icon next to the trees-and-hedges project like this:

  5. If you do not see a sync icon, switch to the My projects tab and back to the Home tab

    This should force Mergin Maps Input to check again for project updates.

  6. Sync the project by pressing the sync icon

  7. Tap the project to open it

    If you zoom in to the hedge you surveyed, you should see it drawn with the new style we made in the last section:

# Labels

Labels can be useful for showing attribute data or other information directly on the map. We'll now add labels to the trees layer so we can see tree species without having to open each tree's attributes:

  1. Double-click the trees layer in QGIS:

    Its layer properties dialog should appear.

  2. Select the Labels tab on the left hand side

  3. Set the labelling mode to Single Labels:

  4. Set the value to the species attribute

  5. Enable Draw text buffer under buffer settings and click OK

  6. Test out these settings in Mergin Maps Input as described in the Trialing changes section above

# Customising the preview panel

We will now learn how to control the content of the preview panel which is shown when you tap a feature in Mergin Maps Input.

The panel for the trees layer looks like the left-hand image below. We will configure it to look like the right-hand image.

  1. Double-click the trees layer in QGIS:

    Its layer properties dialog should appear.

  2. Select the Display tab on the left hand side

  3. Set the display name to species:

    TIP

    If you notice subtle differences in the name / spelling of the the field when you select it in the drop-down list, this is due to the field having been aliased.

  4. Set the HTML map tip to:

     # fields
 condition

  5. Click OK

  6. Test out these settings in Mergin Maps Input as described in the Trialing changes section above

# Controlling layer visibility

You may have noticed that Mergin Maps Input doesn't have a layer switcher. It instead allows users to switch between map themes. A map theme defines which layers will be displayed.

In a moment you'll define the following map themes:

  • All layers
    • Which includes all map layers
  • Hedges
    • Which contains just the hedges layer and background map

  1. In QGIS, click the Manage Map Themes button and select ***Add Theme...***:

  2. Call the theme All layers and click OK

  3. Uncheck the trees and Survey notes layers:

  4. Add another theme like in step 1, calling it Hedges and click OK:

    Switching between the two themes in QGIS should cause the layer visibility to be updated accordingly.

    The themes have now been created.

  5. Test out these settings in Mergin Maps Input as described in the Trialing changes section above

    You can access map themes in Mergin Maps Input from the More menu:

# Project extent

If you experimented with the Zoom to project button in Mergin Maps Input you'll have seen that by default, it zooms to the extent of the somewhat large background map:

This is not very useful so we will learn how to specify the extent that this button will zoom to.

  1. In QGIS, zoom / pan the map to your desired default extent:

  2. Select Project > Properties...

  3. Select the QGIS Server tab and scroll down to WMS capabilities:

  4. Check Advertised extent

  5. Click Use Current Canvas Extent:

  6. Click OK

  7. Test out these settings in Mergin Maps Input as described in the Trialing changes section above

    The Zoom to project button can be found in Mergin Maps Input under the the More menu:

# Learning more

The aim of this tutorial was to introduce you to the main concepts of customising Mergin Maps projects in QGIS and to cover common customisation workflows in a basic way.

← Working Collaboratively →