import javax.swing.*; import java.awt.event.*; import java.awt.*; import java.util.*; /** * StringSpinControl. * This component creates a spin-control (incr/decr of a list of values accessed * by two arrows (one incr, one decr)) for use in such things as getting user * input relating to dates and values. This spin control only deals with strings * * Copyright (C) 2000 Shazron Abdullah * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * @author Shazron Abdullah (implementation) * @date 1999/01/18 * **/ public class StringSpinControl extends JPanel implements ActionListener { private ArrowButton upArrow,downArrow; private JTextField valueDisplay; private int currentIndex; private Vector valueList; //private static int _defaultWidth = 60; //private static int _defaultHeight = 30; //private static Dimension _defaultDimension = new Dimension( _defaultWidth, _defaultHeight ); private static final int HEIGHT_PADDING = 5; private static final int TEXT_WIDTH_PADDING = 5; private static final int ARROW_WIDTH = 7; private static final int COMPONENT_HEIGHT = 24; /** * * Constructor method which takes in a set of values and prepares the * control for use. * * @value theValues a vector of strings which can be displayed and iterated through by the spincontrol * **/ public StringSpinControl(Vector theValues) { valueList = theValues; currentIndex = 0; // Create the buttons and the displayField createControls(); setupEventListeners(); // set the currentValueStr to the first item in the vector if ( valueList != null ) { setValue ( (String) valueList.elementAt(0) ); } // set it to a default size //setSize(_defaultDimension); determineSizeOfControl(); } /** * Determine the size of this, by getting the width of the * longest string to display */ private void determineSizeOfControl() { int textfield_width = 0; FontMetrics myFontMetrics = valueDisplay.getFontMetrics(valueDisplay.getFont()); // iterate through the list, get the largest width for (Enumeration e = valueList.elements(); e.hasMoreElements();){ String theString = (String) e.nextElement(); textfield_width = Math.max( textfield_width, myFontMetrics.stringWidth(theString) ); } //System.out.println(textfield_width); int final_width = textfield_width + ( 2 * TEXT_WIDTH_PADDING ) + ARROW_WIDTH; int final_height = myFontMetrics.getHeight() + HEIGHT_PADDING; // by now we will have the max width setSize( new Dimension(final_width, final_height)); setPreferredSize(new Dimension(final_width,COMPONENT_HEIGHT)); //setBorder(BorderFactory.createLineBorder(Color.green)); } /** * Create the controls for this component. */ private void createControls() { GridBagLayout gridbag = new GridBagLayout(); GridBagConstraints gc = new GridBagConstraints(); setLayout(gridbag); gc.fill = GridBagConstraints.BOTH; /// --- Init the UP arrow upArrow = new ArrowButton(SwingConstants.NORTH); gc.anchor = GridBagConstraints.SOUTHWEST; gc.ipadx = ARROW_WIDTH/2; gc.gridx = 1; gc.gridy = 0; gc.weighty = 0.5; //request any extra vertical space gc.weightx = 0.0; //request any extra horiz space gc.gridwidth = 1; //1 column wide gridbag.setConstraints(upArrow, gc); this.add(upArrow); /// --- Init the DOWN arrow downArrow = new ArrowButton(SwingConstants.SOUTH); gc.anchor = GridBagConstraints.NORTHWEST; gc.gridx = 1; gc.gridy = 1; gc.weighty = 0.5; //request any extra vertical space gc.weightx = 0.0; //request any extra horiz space gc.gridwidth = 1; //1 column wide gridbag.setConstraints(downArrow, gc); this.add(downArrow); /// --- Init the text field valueDisplay = new JTextField(); gc.anchor = GridBagConstraints.EAST; gc.ipadx = TEXT_WIDTH_PADDING; gc.gridx = 0; gc.gridy = 0; gc.weighty = 1.0; //request any extra vertical space gc.weightx = 1.0; //request any extra horiz space gc.gridwidth = 1; //1 column wide gc.gridheight = 2; //2 rows deep gridbag.setConstraints(valueDisplay, gc); this.add(valueDisplay); } /** * */ private void setupEventListeners() { upArrow.addActionListener(this); downArrow.addActionListener(this); } /** * Set the String value in the textfield. */ public void setValue(String value) { valueDisplay.setText(value); } /** * Get the value in the textfield. */ public String getValue() { return valueDisplay.getText(); } /** * Adds a value to the end of the list. */ public void addListValue(String value) { valueList.addElement(value); } /** * Sets the list value at the index to the value provided. */ public void setListValueAt(int index, String value) throws ArrayIndexOutOfBoundsException { valueList.setElementAt(value, index); } /** * Removes the list value from the list. * * @return true if the value was in the list, false if not. */ public boolean removeListValue(String value) { int objIndex = valueList.indexOf(value); boolean retVal = false; if ( objIndex != -1 ) { // found retVal = valueList.removeElement(value); if ( objIndex > getMaxIndex() ) { currentIndex = getMaxIndex(); } } return retVal; } /** * Removes the list value from the list. * */ public void removeListValueAt(int value) throws ArrayIndexOutOfBoundsException { valueList.removeElementAt(value); if ( value > getMaxIndex() ) { currentIndex = getMaxIndex(); } } /** * * Get the number of values available. * **/ public int getMaxIndex() { return Math.max( (valueList.size() - 1), 0 ); } /** * * Get the value from a specified index point. * **/ public String getListValueAt(int index) { return (String) valueList.elementAt(index); } /** * Up arrow button handler. */ private void upArrow_Clicked(ActionEvent e) { /// --- Check if the value in the textfield is a valid value, /// --- increment to next index int index = valueList.indexOf(getValue()) ; if ( index != -1 ){ currentIndex = index; } if ( currentIndex != getMaxIndex() ) { currentIndex++; setValue( (String) valueList.elementAt(currentIndex) ); } } /** * Down arrow button handler. */ private void downArrow_Clicked(ActionEvent e) { /// --- Check if the value in the textfield is a valid value, /// --- increment to next index int index = valueList.indexOf(getValue()) ; if ( index != -1 ) { currentIndex = index; } if ( currentIndex != 0 ) { currentIndex--; setValue( (String) valueList.elementAt(currentIndex) ); } } /** * ActionListener implementation. */ public void actionPerformed(ActionEvent evt) { Object source = evt.getSource(); if (source instanceof ArrowButton) { ArrowButton pab = (ArrowButton) source; if ( pab.equals(upArrow) ) { upArrow_Clicked(evt); } else if ( pab.equals(downArrow) ) { downArrow_Clicked(evt); } } } // Testing purpose public static void main(String args[]) { JFrame j = new JFrame(); Vector myStrings = new Vector(); myStrings.addElement("jan"); myStrings.addElement("feb"); myStrings.addElement("mar"); myStrings.addElement("apr"); myStrings.addElement("may"); myStrings.addElement("jun"); myStrings.addElement("jul"); myStrings.addElement("aug"); myStrings.addElement("sep"); myStrings.addElement("oct"); myStrings.addElement("nov"); myStrings.addElement("december"); StringSpinControl psc = new StringSpinControl(myStrings); psc.addListValue("foo"); psc.addListValue("bar"); //psc.setSize(40,30); j.getContentPane().setLayout(null); j.getContentPane().add(psc); j.setSize(new Dimension(100,100)); j.setVisible(true); } }