// Taken from http://www.java-forums.org/swt/9902-how-use-swt-spinner.html and modified.
package org.atdl4j.ui.swt.util;
import java.math.BigDecimal;
import java.math.RoundingMode;
import org.apache.log4j.Logger;
import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTError;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.graphics.Font;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Text;
import org.eclipse.swt.widgets.TypedListener;
public class SWTNullableSpinner extends Composite
{
private static final Logger logger = Logger.getLogger( SWTNullableSpinner.class );
static final int BUTTON_WIDTH = 20;
Text text;
Button up, down;
BigDecimal minimum, maximum;
BigDecimal increment = new BigDecimal( 1 );
int digits = 0;
public static BigDecimal MIN_INTEGER_VALUE_AS_BIG_DECIMAL = new BigDecimal( -Integer.MAX_VALUE );
public static BigDecimal MAX_INTEGER_VALUE_AS_BIG_DECIMAL = new BigDecimal( Integer.MAX_VALUE );
public SWTNullableSpinner(Composite parent, int style) {
super(parent, style);
/*
GridData gd = new GridData(GridData.FILL_VERTICAL | GridData.HORIZONTAL_ALIGN_BEGINNING);
gd.grabExcessHorizontalSpace = false;
this.setLayoutData(gd);*/
text = new Text(this, SWT.SINGLE | SWT.NONE);
up = new Button(this, SWT.ARROW | SWT.UP);
down = new Button(this, SWT.ARROW | SWT.DOWN);
text.addListener(SWT.Verify, new Listener() {
public void handleEvent(Event e) {
verify(e);
}
});
text.addListener(SWT.Modify, new Listener() {
public void handleEvent(Event e) {
stripExtraDecimalPoints();
}
});
text.addListener(SWT.Traverse, new Listener() {
public void handleEvent(Event e) {
traverse(e);
}
});
up.addListener(SWT.Selection, new Listener() {
public void handleEvent(Event e) {
up();
}
});
down.addListener(SWT.Selection, new Listener() {
public void handleEvent(Event e) {
down();
}
});
addListener(SWT.Resize, new Listener() {
public void handleEvent(Event e) {
resize();
}
});
addListener(SWT.FocusIn, new Listener() {
public void handleEvent(Event e) {
focusIn();
}
});
text.setFont(getFont());
}
void verify(Event e)
{
try
{
if (e.text==null||e.text.equals("")) return;
if ( ( e.text.equals( "." ) ) || ( e.text.endsWith( "." ) ) )
{
// -- Let it go, assume user is entering the decimal place portion and just entered the "." part thus far --
}
else
{
new BigDecimal( e.text ); // validate text as a big decimal
}
}
catch (NumberFormatException ex)
{
e.doit = false;
}
}
void traverse(Event e) {
switch (e.detail) {
case SWT.TRAVERSE_ARROW_PREVIOUS:
if (e.keyCode == SWT.ARROW_UP) {
e.doit = true;
e.detail = SWT.NULL;
up();
}
break;
case SWT.TRAVERSE_ARROW_NEXT:
if (e.keyCode == SWT.ARROW_DOWN) {
e.doit = true;
e.detail = SWT.NULL;
down();
}
break;
}
}
void up()
{
BigDecimal tempValue = getValue();
if ( tempValue == null )
{
if ( ( getMinimum() != null ) && ( ! MIN_INTEGER_VALUE_AS_BIG_DECIMAL.equals( getMinimum() ) ) )
{
setValue( getMinimum() );
}
else
{
setValue( getIncrement() );
}
}
else
{
increment( getIncrement() );
}
notifyListeners(SWT.Selection, new Event());
}
void down()
{
BigDecimal tempValue = getValue();
if ( tempValue == null )
{
if ( ( getMaximum() != null ) && ( ! MAX_INTEGER_VALUE_AS_BIG_DECIMAL.equals( getMaximum() ) ) )
{
setValue( getMaximum() );
}
else
{
setValue( getIncrement() );
}
}
else
{
decrement( getIncrement() );
}
notifyListeners(SWT.Selection, new Event());
}
void focusIn() {
text.setFocus();
}
public void setFont(Font font) {
super.setFont(font);
text.setFont(font);
}
public void setValue(BigDecimal aValue)
{
BigDecimal tempValue = aValue;
// 12/15/2010 Scott Atwell if ( ( getMinimum() != null ) && ( tempValue.compareTo( getMinimum() ) < 0 ) )
if ( ( getMinimum() != null ) && ( tempValue != null ) && ( tempValue.compareTo( getMinimum() ) < 0 ) )
{
tempValue = getMinimum();
}
// 12/15/2010 Scott Atwell else if ( ( getMaximum() != null ) && ( tempValue.compareTo( getMaximum() ) > 0 ) )
else if ( ( getMaximum() != null ) && ( tempValue != null ) && ( tempValue.compareTo( getMaximum() ) > 0 ) )
{
tempValue = getMaximum();
}
// 12/15/2010 Scott Atwell text.setText( tempValue.toPlainString() );
if ( tempValue != null )
{
text.setText( tempValue.toPlainString() );
}
else
{
text.setText( "" );
}
text.selectAll();
text.setFocus();
}
public BigDecimal getValue()
{
if ( ( text.getText()==null ) || ( text.getText().equals("") ) )
{
return null;
}
else
{
// note this is what we had to use in SWTSpinnerWidget when getSelection() returned equiv of BigDecimal.unscaledValue()
// return BigDecimal.valueOf( spinner.getSelection(), spinner.getDigits() );
BigDecimal tempValue = new BigDecimal( text.getText() );
BigDecimal tempValueScaled = tempValue.setScale( getDigits(), RoundingMode.HALF_UP );
if ( ! tempValue.equals( tempValueScaled ) )
{
String tempNewValueString = tempValueScaled.toPlainString();
logger.debug( "tempValue: " + tempValue + " tempValueScaled: " + tempValueScaled + " tempValueScaled.toPlainString(): " + tempNewValueString );
int tempCaretPosition = text.getCaretPosition();
logger.debug( "getCaretPosition(): " + text.getCaretPosition() );
// -- Handle user entering ".12" and formatter converting to "0.12" -- avoid result of "0.21") --
if ( ( tempCaretPosition == 2 ) &&
( text.getText().charAt(0) == '.' ) &&
( tempNewValueString.startsWith( "0." ) ) )
{
// -- we're notified at ".1" but formatted value is converting to "0.1" --
logger.debug("Incrementing CaretPosition (was " + tempCaretPosition + ") to account for formatted string having \".\" converted to \"0.\" automatically." );
tempCaretPosition++;
}
text.setText( tempNewValueString );
text.setSelection( tempCaretPosition, tempCaretPosition );
}
return tempValueScaled;
}
}
void resize() {
Point pt = computeSize(SWT.DEFAULT, SWT.DEFAULT);
int textWidth = pt.x - BUTTON_WIDTH;
int buttonHeight = pt.y / 2;
text.setBounds(0, 0, textWidth, pt.y);
up.setBounds(textWidth, -3, BUTTON_WIDTH, buttonHeight);
down.setBounds(textWidth, pt.y - buttonHeight - 3, BUTTON_WIDTH,
buttonHeight);
}
public Point computeSize(int wHint, int hHint, boolean changed) {
int width = 100;
int height = 20;
if (wHint != SWT.DEFAULT) width = wHint;
if (hHint != SWT.DEFAULT) height = hHint;
return new Point(width, height);
}
public void addSelectionListener(SelectionListener listener) {
if (listener == null)
throw new SWTError(SWT.ERROR_NULL_ARGUMENT);
addListener(SWT.Selection, new TypedListener(listener));
}
public void setDigits(int aDigits) {
digits = aDigits;
}
public int getDigits() {
return digits;
}
public void increment( BigDecimal aIncrement )
{
if ( getValue() != null )
{
setValue( getValue().add( aIncrement ) );
}
else if ( aIncrement != null )
{
setValue( aIncrement );
}
}
public void decrement( BigDecimal aDecrement )
{
if ( getValue() != null )
{
setValue( getValue().subtract( aDecrement ) );
}
else if ( aDecrement != null )
{
setValue( aDecrement );
}
}
/**
* @return the minimum
*/
public BigDecimal getMinimum()
{
return this.minimum;
}
/**
* @param aMinimum the minimum to set
*/
public void setMinimum(BigDecimal aMinimum)
{
this.minimum = aMinimum;
}
/**
* @return the maximum
*/
public BigDecimal getMaximum()
{
return this.maximum;
}
/**
* @param aMaximum the maximum to set
*/
public void setMaximum(BigDecimal aMaximum)
{
this.maximum = aMaximum;
}
/**
* @return the increment
*/
public BigDecimal getIncrement()
{
return this.increment;
}
/**
* @param aIncrement the increment to set
*/
public void setIncrement(BigDecimal aIncrement)
{
this.increment = aIncrement;
}
public void addListener(Listener listener)
{
text.addListener( SWT.Modify, listener );
}
public void removeListener(Listener listener)
{
text.removeListener( SWT.Modify, listener );
}
/**
* Spinners with decimal places use DecimalFormatter to automatically render/re-render the string value.
* When entering a decimal value via keyboard within an empty Spinner text field, the displayed value
* will automatically adjust (eg entering "1.23" in a field with 2 decimal places will render "1.23.00")
* without the use of this adjustment method.
*
* @return true if extra decimal point characters had to be stripped
*/
private boolean stripExtraDecimalPoints()
{
String tempText = text.getText();
if ( tempText.length() > 0 )
{
int tempFirstDecimalPoint = tempText.indexOf( '.', 0 );
if ( tempFirstDecimalPoint >= 0 )
{
int tempNextDecimalPoint = tempText.indexOf( '.', (tempFirstDecimalPoint + 1) );
if ( tempNextDecimalPoint >= 0 )
{
logger.debug(" Multiple decimal points... tempText: " + tempText );
boolean tempDecimalPointFound = false;
StringBuffer tempStringBuffer = new StringBuffer();
for ( int i=0; i < tempText.length(); i++ )
{
if ( tempText.charAt( i ) == '.' )
{
if ( ! tempDecimalPointFound )
{
tempDecimalPointFound = true;
}
else
{
// skip/omit the character
continue;
}
}
tempStringBuffer.append( tempText.charAt( i ) );
}
logger.debug(" text.setText( tempStringBuffer.toString() ): " + tempStringBuffer.toString() );
int tempCaretPosition = text.getCaretPosition();
text.setText( tempStringBuffer.toString() );
text.setSelection( tempCaretPosition, tempCaretPosition );
return true;
}
}
}
return false;
}
}
