borland Packages  Class Hierarchy  jbcl.control Package  Index 

ChoiceControl component

java.lang.Object
   +----java.awt.Component
           +----java.awt.Choice
                   +----borland.jbcl.view.ChoiceView
                           +----borland.jbcl.control.ChoiceControl

About the ChoiceControl component

Variables  Constructors  Properties  Methods  Event Listeners

Implements AccessListener, ColumnAware, DataChangeListener, DataSetAware, NavigationListener, SingletonModel, SingletonModelListener, WritableSingletonModel, BlackBox, SingletonModelView, KeyListener, ImageObserver, ItemSelectable, MenuContainer, Serializable, EventListener

The ChoiceControl is a drop-down list of choices. The current selection is visible.

If the control is connected to a column in a data set through the dataSet and columnName properties, it displays the values in the specified column of the data set. In this case, ChoiceControl is a data-aware control.

If ChoiceControl is not being used as a data-aware control, the choices available come from the items property. To add items to the control, use the addItem() or add() methods. To insert an item, call insert(). To remove items, call remove() or removeAll(). The itemCount property contains the number of items in the control.

To select an item in the ChoiceControl, call the select() method. The selectedIndex property contains the index number of the selected item in the control, and the selectedItem property contains the String that represents the selected item.

When an item in the choice control is selected, events such as modelContentChanged and itemStateChanged occur. The code that you write in response to one or more of these events determines what happens with the selected item.

Example


// After selecting an animal name from the choice menu, the name appears in
// the text field.
import java.awt.*;
import java.awt.event.*;
import borland.jbcl.control.*;
import borland.jbcl.layout.*;

public class ChoiceEx {

    public ChoiceEx() {
        ChoiceFrame frame = new ChoiceFrame();
        frame.pack();
        frame.setVisible(true);
    }

    static public void main(String[] args) {
        new ChoiceEx();
    }
}

class ChoiceFrame extends DecoratedFrame {
    BevelPanel bev = new BevelPanel();
    ChoiceControl choiceCtrl = new ChoiceControl();
    TextFieldControl textFieldControl = new TextFieldControl();

    public ChoiceFrame() {
        this.setTitle("Animals");
        choiceCtrl.setItems(new String[] {"Koala", "Monkey", "Lark", "Puffin"});
        this.add(bev);
        bev.add(choiceCtrl, new XYConstraints(30, 10, -1, -1));
        bev.add(textFieldControl, new XYConstraints(0, 50, 125, -1));
        textFieldControl.setText("Koala");
        choiceCtrl.addItemListener(new ChoiceControlItemAdapter(this));
    }

    void choiceControlItemStateChanged(ItemEvent itemEvent) {
        textFieldControl.setText((String)choiceCtrl.get());
    }
}

class ChoiceControlItemAdapter implements java.awt.event.ItemListener {

    ChoiceControlItemAdapter(ChoiceFrame choiceframe) {
        this.choiceframe = choiceframe;
    }

    ChoiceFrame choiceframe;

    public void itemStateChanged(ItemEvent itemEvent) {
        choiceframe.choiceControlItemStateChanged(itemEvent);
    }
}

For an example that uses a ChoiceControl, see the project file Cardlayout.jpr located in the jbuilder\samples\borland\samples\jbcl\cardlayout directory of your JBuilder installation. This sample uses a CardLayout panel that is controlled by a ChoiceControl, ListControl, and TabsetControl.


ChoiceControl variables

Variables implemented in java.awt.Component

ChoiceControl constructors

ChoiceControl properties

*Read-only properties **Write-only properties

Properties implemented in this class

Properties implemented in borland.jbcl.view.ChoiceView

Properties implemented in java.awt.Choice

Properties implemented in java.awt.Component

Properties implemented in java.lang.Object

ChoiceControl methods

Methods implemented in this class

Methods implemented in borland.jbcl.view.ChoiceView

Methods implemented in java.awt.Choice

Methods implemented in java.awt.Component

Methods implemented in java.lang.Object

ChoiceControl event listeners


ChoiceControl constructors

ChoiceControl()

  public ChoiceControl()

Constructs a ChoiceControl with default property values.


ChoiceControl properties

columnName

 public String getColumnName()
 public void setColumnName(java.lang.String newColumnName)
Identifies a column of the specified borland.jbcl.dataset.DataSet object that contains the items displayed in the ChoiceControl. setColumnName() sets the model to SingletonDataSetManager using the specified column of the specified DataSet.

dataSet

 public DataSet getDataSet()
 public void setDataSet(borland.jbcl.dataset.DataSet newDataSet)
Specifies a borland.jbcl.dataset.DataSet that contains the column that displays in the ChoiceControl.

model

 public void setModel(borland.jbcl.model.SingletonModel sm)

Checks for a recursive model, then calls borland.jbcl.view.ChoiceView.setModel(SingletonModel), which specifies the model object required for access to a list of choices. ChoiceView requires a VectorModel object.


ChoiceControl methods

addNotify()

  public void addNotify()

Calls addNotify() of java.awt.Choice to create the ChoiceControl's peer. This peer allows changing the look of the ChoiceControl without changing its functionality. Initializes the ChoiceControl if not already initialized. Opens the DataSet supplying items for this ChoiceControl.

Overrides: java.awt.Choice.addNotify()

setItems(borland.jbcl.dataset.DataSet, java.lang.String)

  public void setItems(borland.jbcl.dataset.DataSet dataSet, java.lang.String columnName)

Populates the ChoiceControl using the strings from the specified column of the specified DataSet.

Parameters:

dataSet
The DataSet to use to populate the ChoiceControl.
columnName
The column of dataSet to use.

ChoiceControl event listeners

This component is a source for the following event sets. For information on the standard AWT event sets, see Standard Java events. For information on the JBCL event sets, see Events in JBCL.

component

 public synchronized void addComponentListener(java.awt.event.ComponentListener )
 public synchronized void removeComponentListener(java.awt.event.ComponentListener )

focus

 public synchronized void addFocusListener(java.awt.event.FocusListener )
 public synchronized void removeFocusListener(java.awt.event.FocusListener )

item

 public synchronized void addItemListener(java.awt.event.ItemListener )
 public synchronized void removeItemListener(java.awt.event.ItemListener )

key

 public synchronized void addKeyListener(java.awt.event.KeyListener )
 public synchronized void removeKeyListener(java.awt.event.KeyListener )

model

 public void addModelListener(borland.jbcl.model.SingletonModelListener listener)
 public void removeModelListener(borland.jbcl.model.SingletonModelListener listener)

mouse

 public synchronized void addMouseListener(java.awt.event.MouseListener )
 public synchronized void removeMouseListener(java.awt.event.MouseListener )

mouseMotion

 public synchronized void addMouseMotionListener(java.awt.event.MouseMotionListener )
 public synchronized void removeMouseMotionListener(java.awt.event.MouseMotionListener )