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SPEAKER 1: Let's write a program with a
graphical user interface as well as

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a text field that allows the user to
type in some string and hit Enter, at

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which point that string is
provided to my program.

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Much like GetString in the CS50 Library
works, but this time with a

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graphical user interface.

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Let's get started.

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I've already written some skeletal code,
so let's now fill in a blank.

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GTextField, calling it field.

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Assigning it the return value
of newGTextField.

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And specifying that I'd like to see
10 characters from the user on

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the screen at a time.

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Let's next call setActionCommand,
passing in field, passing in say,

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quote unquote "input." In other words,
let's associate with this text field

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unique string "input." just in case my
user interface has multiple text

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fields, this string will uniquely
identify this one.

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Let's next call addToRegion, passing in
window, passing in field, passing

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in quote unquote "SOUTH," a unique
identifier defined in the Stanford

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Portable Library that specifies
the southern or bottom

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region of my user interface.

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Let's next induce an infinite loop.

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And inside of this loop, let's
listen for two events.

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One, the user closing the window.

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Or two, the user typing something
into that text field.

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Let's declare a gActionEvent.

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Calling it event.

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Assigning it the return
value of waitForEvent.

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Specifying that the type of event we'd
like to listen for is an ACTION_EVENT,

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where ACTION_EVENT is a constant
declared in the Stanford Portable

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Library that specifies
that type of event.

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Let's next check if, getEventType,
passing in event, equals equals

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WINDOW_CLOSED, another constant declared
in the Stanford Portable

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Library that indicates that
the window has closed.

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Then let's simply break out
of this infinite loop.

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Otherwise, let's now check whether the
user has typed something into that

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text field.

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If, string compare, getActionCommand,
passing in event, comma quote unquote

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"input" equals equals 0.

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In other words, if the unique identifier
the text field into which

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the user has typed something is equal
to that unique identifier that I

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specified earlier, let's
do the following.

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Printf quote unquote "%s was inputted."
And let's plug-in for that

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%s the return value of getText passing
in the field, where getText is another

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function, defined in the Stanford
Portable Library, that gets the text

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from a field.

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Let's now save, compile,
and run this program.

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Make text.

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./text.

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There's my user interface, and there's
that text field at the bottom.

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Let's type something like
h-e-l-l-o, Enter.

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And there, at the bottom of my
console window, indeed we see

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that "hello" was inputted.

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