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FIGURE 24-6
Sample output from the SBDemo applet
Using a TextField
The TextField class implements a single-line text-entry area, usually called an edit control.
Text fields allow the user to enter strings and to edit the text using the arrow keys, cut and
paste keys, and mouse selections. TextField is a subclass of TextComponent. TextField
defines the following constructors:
TextField( ) throws HeadlessException
TextField(int numChars) throws HeadlessException
TextField(String str) throws HeadlessException
TextField(String str, int numChars) throws HeadlessException
The first version creates a default text field. The second form creates a text field that is
numChars characters wide. The third form initializes the text field with the string contained
in str. The fourth form initializes a text field and sets its width.
TextField (and its superclass TextComponent) provides several methods that allow you
to utilize a text field. To obtain the string currently contained in the text field, call getText( ).
To set the text, call setText( ). These methods are as follows:
String getText( )
void setText(String str)
Here, str is the new string.
The user can select a portion of the text in a text field. Also, you can select a portion of
text under program control by using select( ). Your program can obtain the currently selected
text by calling getSelectedText( ). These methods are shown here:
String getSelectedText( )
void select(int startIndex, int endIndex)
getSelectedText( ) returns the selected text. The select( ) method selects the characters
beginning at startIndex and ending at endIndex1.
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