UNIT 5: APP INVENTOR 2 (LEARN TO MAKE YOUR OWN APP'S)

PaintPot - App Inventor 2 - Intermediate Tutorial

 

This tutorial introduces the Canvas component for creating simple, two-dimensional (2D) graphics.

 

You’ll build PaintPot, an app that lets the user draw on the screen in different  colors, and then update it so that the user can take a picture and draw on that instead. On a historical note, PaintPot was one of the first  programs developed to demonstrate the potential of personal computers, as far back as the 1970s. Back then, making something like this simple drawing app was a very complex undertaking, and the results were pretty unpolished. But now, with App Inventor, anyone can quickly put together a fairly cool drawing app, which is a great starting point for building 2D games.

 

With the PaintPot app, you can:

 

• Dip your finger into a virtual paint pot to draw in that color.

• Drag your finger along the screen to draw a line.

• Poke the screen to make dots.

• Use the button at the bottom to wipe the screen clean.

• Change the dot size to large or small with the buttons at

the bottom.

• Take a picture with the camera and then draw on that picture.

 

What You’ll Learn

 

This tutorial introduces the following concepts:

 

• Using the Canvas component for drawing.

 

• Handling touch and drag events on the device surface.

 

• Controlling screen layout with arrangement components.

 

• Using event handlers that have arguments.

 

• Defining variables to remember things like the dot size

the user has chosen for drawing.