An Introduction to the QGIS Desktop

In this exercise you will:

  • Add data to the QGIS software
  • Work with map layers
  • Navigate around the map using functions on the Tools toolbar
  • Identify features on the map
  • Dock and undock toolbars
  • Add extra toolbars to the QGIS Desktop.

Add Data to the QGIS Desktop

  1. Start the QGIS Desktop software via the start menu in Windows or Launchpad on your Mac.

  2. To load a vector layer, select Layer > Add Layer > Add Vector Layer from the main menu or click on the Add Vector layer button alt text

  3. In the Add vector layer window, click on the Browse button, find the Exercise2 folder and double click to open it.

  4. Change the filetpe to ‘ESRI Shapefiles (*.shp *.SHP)’ and click on wyorkmap.shp, which contains administrative ward boundaries for West Yorkshire. Select Open followed by Open again on the Add vector layer window.

  5. Repeat the operation to add the schools.shp to this layer, which shows the location of schools in the West Yorkshire region.

Work with Map Layers

  1. Click on the wyorkmap name in the Layers panel (panel on the bottom left) and press F2 (or right click and ‘rename’). Rename this to West Yorkshire.

  2. Click on the schools name in the Layers panel and rename this to Schools.

  3. Although you have changed the name here in QGIS, you have not changed the actual map filenames.

  4. Click the box to the left of the Schools layer in the Layers window. Note how this turns the display of the schools off.

    alt text

  5. Turn the schools layer back on and now repeat with the West Yorkshire layer. You can see how easy it is to control what is displayed in the main map area.

Change the Order of Display

The order of the layers in the Layers window determines the order in which QGIS draws these layers in the main map area. QGIS starts drawing from the bottom upwards so first it draws the West Yorkshire boundaries and then it places the Schools on top of the boundaries.

You can control the order of the layers by dragging them up and down the list.

  1. Click on the Schools layer, dragging it below the West Yorkshire boundaries. What happened to the Schools layer? Why is this? How could you see the Schools layer without dragging the layer back to the top?

  2. Practice dragging the layers up and down a few times until you are happy you can do this with ease.

Zooming enlarges or reduces the display and panning shifts the display to reveal different areas of the map. The zoom and pan buttons are found on the Tools toolbar: alt text

  1. Click on the Zoom In button alt text and then click anywhere on the map to zoom in.

  2. Click on the Zoom Full button alt text to zoom to a full display of all layers regardless of whether you have turned them on or off. For example, if you had a map of Austria and a map of Vienna, the full extent button would zoom out to the Austrian extent.

  3. Click back onto the Zoom In button. Click and hold down the mouse button, dragging across an area on the map.

  4. Click the Zoom to Layer button alt text. This zooms back out to show both layers.

  5. Experiment with the Zoom Out alt text in the same way as you did for the Zoom In.

  6. Click the Pan button alt text. Move your cursor anywhere on the map display. Hold down the left mouse button and drag the mouse in any direction. Release the mouse button.

    Remember you can use the Zoom Full button anytime you want to return to the full map.

  7. Click the Zoom Last button alt text. This will return the map back to its previous extent. You can continue to press this button to go back through all the previous views.

  8. Click the Zoom Next button alt text. This will move you forward through the extents that you viewed. QGIS basically remembers the different extents you viewed in the order that you viewed them.

Identify Features on the Map

This tool allows you to find out information about different features that appear on your map.

  1. Zoom in so that you can see some of the Schools clearly.

  2. Click on the Schools layer in the Layers window on the left.

  3. This will enable the Identify Features button alt text, which you will find in the rows of many buttons near the top of the main QGIS window. Click on this button.

  4. Then click on a school in the map display. What information is revealed to you?

    NOTE: If the school symbols are too small, double-click on the actual symbol to the left of the Schools Layer in the Layers window. This will bring up the Layer Properties window. You will then see an option to change the size in the Style tab.

  5. Now click on the West Yorkshire layer, click on the Identify Features button and then click on the area surrounding a school. What information do you get instead?

Dock and Undock Toolbars

QGIS has many toolbars. These toolbars can be moved around the application and then ‘docked’ in different places to suit the way you work.

  1. Find a toolbar in the application and undock it by dragging it from the left hand side. Move it around your screen.

  2. Try undocking and docking some of the other toolbars. Are there any toolbars that you cannot undock?

  3. Now try undocking the Layers Window and move it around your screen. To dock it again, double click on the title bar of the window.

  4. Can you undock the map display window?

Add Extra Toolbars to the QGIS Desktop

Toolbars can be made visible by selecting View > Toolbars from the main menu. Toolbars that are currently visible will have a check mark in front of their name. You simply check or uncheck the toolbar as they are required.

  1. Select View > Toolbars. What toolbars are currently available to you?

  2. Of these, how many are currently checked?

  3. Check any one of the toolbars that is currently not checked. What happens?

  4. Move this new toolbar around the screen.

  5. Finally, remove this toolbar.

Now move on to exercise three