← All projects

Part 6 of this project

Brushes

Switch brush size and hardness-lite

Goal for this part

Switch brush size and hardness-lite.

Treat 06-Brushes as the source of truth for this checkpoint. If your local tree drifted, re-clone that folder rather than mixing files from neighbors.

What you should already know

You do not need prior Qt Quick experience for part 1. Later parts assume you finished the earlier snapshots on the same machine.

  • You can open a terminal and run python3
  • You are comfortable editing a .py file and saving it
  • You have a desktop session (not a headless SSH box without display forwarding)

Why Qt Quick fits Brushnook

Qt Quick (QML) is a different path from widgets—declarative UI plus a Canvas for drawing strokes.

Expose brush settings from Python to QML. Keep the stroke list serializable so undo stays understandable.

Checkpoint

After you run the snapshot, you should recognize the behavior described in the goal—before you move on. If the window (or server) never appears, stop and fix the run steps.

Code shape

Snapshots stay small on purpose. Look for this kind of core call as you read the folder:

ctx.beginPath(); ctx.moveTo(x, y);

How to run it

Clone the teaching repo, open 06-Brushes, install what the README asks for, then run python app.py.

git clone https://github.com/michaeldunga1/fcc-qml-paint.git
cd fcc-qml-paint/06-Brushes
python3 -m venv .venv
source .venv/bin/activate
pip install -r ../requirements.txt
python app.py

Common mistakes

  • Ignoring platform-specific install notes in the snapshot README
  • Updating the UI without writing through to storage
  • Deleting records that still have dependents
  • Leaving dialogs modal with no cancel path

Related tutorials