Flash drag and drop tutorial

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Overview

Dragging and dropping objects is a popular brick in edutainment programs. This is part of Flash CS3 tutorials. I will expand this article sometimes. - Daniel K. Schneider 18:13, 9 September 2007 (MEST).

Learning goals

Learn how to create simple drag and drop programs with Flash 9 (CS3) components

Learn a little bit of Action Script 3

Prerequisites

Flash CS3 desktop tutorial

Flash drawing tutorial

flash button tutorial

Moving on

The Flash article has a list of other tutorials.

Flash Video component tutorial

Quality

This text should technical people get going and may not be good enough for self-learning beginners. It can be used as handout in a "hands-on" class. That is what Daniel K. Schneider made it for...

Level

It aims at beginners. More advanced features and tricks are not explained here.

Learning materials

Grab the various *.fla files from here:

http://tecfa.unige.ch/guides/flash/ex/drag-and-drop-intro/ (not yet sorry)

The executive summary

• Draw something on the canevas
• Transform it to a movie symbol (buttons don't work)
• Assign an instance name
• Instance_name.startDrag()
• Instance_name.stopDrag()

Introduction - simple dragging code

Step 1 - Draw an object

• Anything you like

Step 2 - Transform it into a Movie Clip

• Select all if you got several objects, then assemble maybe
• Right-click on the object
• Give it a name in the properties panel !

Step 3 - Adapt code below

Most simple drag and drop

// Register mouse event functions
blue_btn.addEventListener(MouseEvent.MOUSE_DOWN, mouseDownHandler);
blue_btn.addEventListener(MouseEvent.MOUSE_UP, mouseUpHandler);

red_btn.addEventListener(MouseEvent.MOUSE_DOWN, mouseDownHandler);
red_btn.addEventListener(MouseEvent.MOUSE_UP, mouseUpHandler);

// Define a mouse down handler (user is dragging)
function mouseDownHandler(evt:MouseEvent):void {
	var object = evt.target;
	// we should limit dragging to the area inside the canvas
	object.useHandCursor = true;
	object.startDrag();
}

function mouseUpHandler(evt:MouseEvent):void {
	var obj = evt.target;
		obj.stopDrag();
}

Results

• Get the source from http://tecfa.unige.ch/guides/flash/ex/drag-and-drop-intro/