Book Image

QGIS Python Programming Cookbook, Second Edition - Second Edition

By : Joel Lawhead
Book Image

QGIS Python Programming Cookbook, Second Edition - Second Edition

By: Joel Lawhead

Overview of this book

QGIS is a desktop geographic information system that facilitates data viewing, editing, and analysis. Paired with the most efficient scripting language—Python, we can write effective scripts that extend the core functionality of QGIS. Based on version QGIS 2.18, this book will teach you how to write Python code that works with spatial data to automate geoprocessing tasks in QGIS. It will cover topics such as querying and editing vector data and using raster data. You will also learn to create, edit, and optimize a vector layer for faster queries, reproject a vector layer, reduce the number of vertices in a vector layer without losing critical data, and convert a raster to a vector. Following this, you will work through recipes that will help you compose static maps, create heavily customized maps, and add specialized labels and annotations. As well as this, we’ll also share a few tips and tricks based on different aspects of QGIS.
Table of Contents (16 chapters)
QGIS Python Programming Cookbook - Second Edition
About the Author
About the Reviewer
Customer Feedback

Displaying a message in the status bar

The status bar in QGIS displays a variety of information in all sorts of contexts. It can be used for static information such as the current project projection or for real-time scrolling information such as the mouse coordinates. In this recipe, we'll print the current time to the status bar.

Getting ready

Open the QGIS Python console by selecting the Plugins menu and then clicking on Python Console.

How to do it...

All we need to do is call the status bar message method with the current time:

  1. First, we import the time module:

            import time 
  2. Then, we call the showMessage() method of the status bar with the current time and date:


How it works...

QGIS automatically places the message in an open space on the status bar. We placed a simple message in the status bar, but you can also add pretty much any other widget as well. The following screenshot shows the timestamp on the bottom...