TOE chart

A TOE chart simply means a chart that shows the Tasks, Objects and Events. You compile this chart to help you with your planning process in creating a new program. The benefit of a TOE chart is that you can already decide what names to give your control objects. In addition to this, you can check your TOE chart if you forget or get confused with the name of a control object.

In the task column, you list all the functions that the program needs to perform, e.g. get the name of the client, get the items purchased, displaying the output, ending the program and closing the program. These are all tasks that the program will perform.

The object column will contain a list of objects or controls needed to perform each task of the program, e.g. textboxes, labels, buttons, etc.

The event column will contain a list of the events associated with the listed objects, e.g. a button control will require a click event. Not all objects in a user interface will need an event to occur for the object to perform its assigned tasks.

You can draw the TOE chart on a piece of paper, or you can type it out. This chart will form part of the other documents you use when designing a program. Other documents may include flowcharts, examples of existing documentation that a company uses, like invoices, etc.

When you create a very large program it is often useful to arrange the TOE chart by object. List each object only once. Then list the task and event for each object.

TASK	OBJECT	EVENT
.
Get user information:
Customer name	NameTextBox
Customer surname	SurnameTextBox
Customer telephone number	TelTextBox
.
Get sales information:
Item name	ItemTextBox
Item description	ItemDesTextBox
Item price	ItemPriceTextBox
Number of items	ItemNumTextBox
.
Calculate the total of items purchased	CalcButton	Click
.
Display invoice output:
Customer name	NameLabel
Customer surname	SurnameLabel
Customer telephone number	TelLabel
Item name	ItemLabel
Item description	ItemDesLabel
Item price	ItemPriceLabel
Number of items purchased	ItemNumLabel
Total price	TotalPriceLabel
.
End the program	ExitButton	Click
.
Clear the screen for next sale	ClearButton	Click