Text components are available for simple text and for enhanced text and
editing panes. VisualAge provides text beans from the
com.sun.java.swing,
com.sun.java.swing.text, and
java.awt packages. Although Swing and AWT beans can
be mixed, it is inadvisable.
You can add a text bean to enable text input or provide a label.
- Add one of the following text beans:
- Define initial characteristics of the text component.
- Defining label text or initial input text
- Enter text for the text property in the text component's
property sheet. For a multiline text area, use \n to
denote a new line.
- Adding a label graphic
- For a JLabel bean, you can add a graphic to the label. Select a
graphic file for the icon property in the label's property
sheet. Use the horizontalTextPosition property to specify
the position of text relative to the graphic. The position choices are
LEFT, CENTER, and RIGHT. The default
choice is RIGHT. Set the iconTextGap property to
specify the space between the icon and label text.
- Defining keyboard access to an input field
- For Swing text input components, you can define keyboard shortcuts to
place the focus in the input field or area.
- To define an accelerator for a text field, specify the accelerator
character, enclosed in single quotes, for the focusAccelerator
property in the text component's property sheet. If you define
tool tip text for the text field, the accelerator is displayed with the tool
tip text. For example, if you specify 'a' as the
focusAccelerator value, alt+A appears after tool tip
text when the user moves the mouse pointer over the fext field.
- To define a label mnemonic for a text field, specify the mnemonic
character, enclosed in single quotes, for the displayedMnemonic
property in the JLabel's property sheet.
- Aligning text
- Select an alignment choice for the horizontalAlignment or
alignment property in the text component's property
sheet. The alignment choices are LEFT, CENTER,
and RIGHT.
- Selecting initial text
- To select the initial text, set the selectionStart and
selectionEnd properties in the text component's property
sheet. These values are offsets from the beginning of the text, which
is at offset 0. To select all text without determining the initial text
length, specify selection from offset 0 to an offset that you consider to be
larger than the initial text length.
- Defining a minimum size for layout managers
- Some layout managers use a minimum size for placement of
components. To specify a minimum width for a text area, enter the
width, in characters, for the columns property in the text
component's property sheet. To specify a minimum height for a text
area, enter the number of rows for the rows property.
- Hiding input text
- To hide input text, either use a JPasswordField bean or specify an echo
character for the echoChar property in the text component's
property sheet.
- Preventing text modification in a text area
- To prevent any input in a text area, set the editable property
to False in the text component's property sheet.
- Making a text area scrollable
- An AWT TextArea implements scrolling, duplicating the capability of a
ScrollPane. A JTextArea does not implement scrolling itself, but uses
the scrolling capability of a JScrollPane in which it is placed. If you
want a JTextArea to be scrollable, drop it in a JScrollPane.
- Defining tool tip text for a text component
- For Swing components, you can specify tool tip text, also known as
fly-over text or hover help. Enter text for the toolTipText
property in the component's property sheet.
- Defining initial availability
- By default, the component is initially enabled for user
interaction. To initially disable the component, set the
enabled property to False in the component's
property sheet.
- Provide runtime logic for the text component.
- Synchronizing text
- If you need to synchronize user input between two text components, do the
following:
- Connect their text properties.
- Open the connection properties.
- Associate each end of the connection with the
keyReleased(java.awt.event.KeyEvent)
event.
If you need to synchronize text that you set by connection from another
source, make connections to both text components.
- Disabling a text component
- To disable a text component when an event occurs, connect the event to the
component's enabled property and set the connection parameter
value to False.
- Enabling a text component
- To enable a text component when an event occurs, connect the event to the
component's enabled property and set the connection parameter
value to True.
For examples, see the LayoutManagers class in the
com.ibm.ivj.examples.vc.swing.layoutmanagers
and
com.ibm.ivj.examples.vc.layoutmanagers
packages and the Amortization class in the
com.ibm.ivj.examples.vc.swing.mortgageamortizer
and
com.ibm.ivj.examples.vc.mortgageamortizer
packages. These examples are shipped in the IBM Java Examples
project.
Working with Beans Visually
Using VisualAge Beans in Visual Composition
Adding the IBM Java Examples project
Text Beans
LayoutManagers Sample
MortgageAmortizor Sample
