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Java Platform 1.2 Beta 4 |
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SUMMARY: INNER | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Object | +--java.awt.Component | +--java.awt.Choice
Choice
class presents a pop-up menu of choices.
The current choice is displayed as the title of the menu.
The following code example produces a pop-up menu:
Choice ColorChooser = new Choice(); ColorChooser.add("Green"); ColorChooser.add("Red"); ColorChooser.add("Blue");
After this choice menu has been added to a panel, it appears as follows in its normal state:
In the picture, "Green"
is the current choice.
Pushing the mouse button down on the object causes a menu to
appear with the current choice highlighted.
Fields inherited from class java.awt.Component | |
BOTTOM_ALIGNMENT , CENTER_ALIGNMENT , LEFT_ALIGNMENT , RIGHT_ALIGNMENT , TOP_ALIGNMENT |
Constructor Summary | |
Choice()
Creates a new choice menu. |
Method Summary | |
void | add(String item)
Adds an item to this Choice menu. |
void | addItem(String item)
Adds an item to this Choice. |
void | addItemListener(ItemListener l)
Adds the specified item listener to receive item events from this Choice menu. |
void | addNotify()
Creates the Choice's peer. |
int | countItems()
Deprecated. As of JDK version 1.1, replaced by getItemCount() . |
String | getItem(int index)
Gets the string at the specified index in this Choice menu. |
int | getItemCount()
Returns the number of items in this Choice menu. |
int | getSelectedIndex()
Returns the index of the currently selected item. |
String | getSelectedItem()
Gets a representation of the current choice as a string. |
Object[] | getSelectedObjects()
Returns an array (length 1) containing the currently selected item. |
void | insert(String item,
int index)
Inserts the item into this choice at the specified position. |
protected String | paramString()
Returns the parameter string representing the state of this choice menu. |
protected void | processEvent(AWTEvent e)
Processes events on this choice. |
protected void | processItemEvent(ItemEvent e)
Processes item events occurring on this Choice
menu by dispatching them to any registered
ItemListener objects.
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void | remove(int position)
Removes an item from the choice menu at the specified position. |
void | remove(String item)
Remove the first occurrence of item
from the Choice menu. |
void | removeAll()
Removes all items from the choice menu. |
void | removeItemListener(ItemListener l)
Removes the specified item listener so that it no longer receives item events from this Choice menu. |
void | select(int pos)
Sets the selected item in this Choice menu to be the
item at the specified position. |
void | select(String str)
Sets the selected item in this Choice menu
to be the item whose name is equal to the specified string.
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Methods inherited from class java.lang.Object | |
clone , equals , finalize , getClass , hashCode , notify , notifyAll , wait , wait , wait |
Constructor Detail |
public Choice()
By default, the first item added to the choice menu becomes the
selected item, until a different selection is made by the user
by calling one of the select
methods.
select(int)
,
select(java.lang.String)
Method Detail |
public void addNotify()
Toolkit.createChoice(java.awt.Choice)
,
Component.getToolkit()
public int getItemCount()
Choice
menu.getItem(int)
public int countItems()
getItemCount()
.public String getItem(int index)
Choice
menu.
index
- the index at which to begin.getItemCount()
public void add(String item)
Choice
menu.
item
- the item to be addednull
.public void addItem(String item)
item
- the item to be addedpublic void insert(String item, int index)
item
- the item to be inserted
index
- the position at which the item should be insertedpublic void remove(String item)
item
from the Choice
menu.
item
- the item to remove from this Choice
menu.public void remove(int position)
position
- the position of the item.public void removeAll()
remove(java.lang.String)
public String getSelectedItem()
getSelectedIndex()
public Object[] getSelectedObjects()
ItemSelectable
public int getSelectedIndex()
getSelectedItem()
public void select(int pos)
Choice
menu to be the
item at the specified position.
pos
- the positon of the selected item.getSelectedItem()
,
getSelectedIndex()
public void select(String str)
Choice
menu
to be the item whose name is equal to the specified string.
If more than one item matches (is equal to) the specified string,
the one with the smallest index is selected.
str
- the specified stringgetSelectedItem()
,
getSelectedIndex()
public void addItemListener(ItemListener l)
Choice
menu.
l
- the item listener.ItemEvent
,
ItemListener
,
removeItemListener(java.awt.event.ItemListener)
public void removeItemListener(ItemListener l)
Choice
menu.
l
- the item listener.ItemEvent
,
ItemListener
,
addItemListener(java.awt.event.ItemListener)
protected void processEvent(AWTEvent e)
ItemEvent
, it invokes the
processItemEvent
method. Otherwise, it calls its
superclass's processEvent
method.
e
- the event.ItemEvent
,
processItemEvent(java.awt.event.ItemEvent)
protected void processItemEvent(ItemEvent e)
Choice
menu by dispatching them to any registered
ItemListener
objects.
This method is not called unless item events are enabled for this component. Item events are enabled when one of the following occurs:
ItemListener
object is registered
via addItemListener
.
enableEvents
.
e
- the item event.ItemEvent
,
ItemListener
,
addItemListener(java.awt.event.ItemListener)
,
Component.enableEvents(long)
protected String paramString()
Choice
menu.
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Java Platform 1.2 Beta 4 |
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SUMMARY: INNER | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |