A Different Way to use JPopupMenu

To Swing developers, JPopupMenu must be a familiar component. However, most people only take it as 'right-click popup menu’. Actually, there are much more usages of JPopupMenu, so with the help of it, all the requirement involving popup effects can be met. For example, if we input "import java.util." with development tools and the drop up menu with the probable options listed will pop up automatically when inputting ".".

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Point;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;

import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPopupMenu;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.SwingConstants;
import javax.swing.SwingUtilities;

import twaver.TWaverUtil;

public class PopupTipDemo extends JFrame {

    String[] messages = new String[] {
            "getTWaverJava()",
            "getTWaverWeb()",
            "getTWaverFlex()",
            "getTWaverDotNET()",
            "getTWaverGIS()",
            "getTWaverHTML5()",
            "getTWaverJavaFX()",
            "getTWaver...", };

    JLabel label = new JLabel("TWaver makes everything easy!");
    JList list = new JList(messages);
    JComponent tip = new JScrollPane(list);
    JTextArea text = new JTextArea();
    JPopupMenu popup = new JPopupMenu();

    public PopupTipDemo() {
        super("www.servasoftware.com");
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.getContentPane().setLayout(new BorderLayout());
        this.getContentPane().add(new JScrollPane(text), BorderLayout.CENTER);
        this.tip.setPreferredSize(new Dimension(230, 80));
        this.label.setForeground(Color.BLUE);
        this.label.setHorizontalAlignment(SwingConstants.CENTER);
        this.popup.setLayout(new BorderLayout());
        this.popup.add(label, BorderLayout.NORTH);
        this.popup.add(tip, BorderLayout.CENTER);

        this.text.setText("// Try to press '.'\nimport twaver.Node;\nimport twaver.Link;\nimport twaver.network");
        this.text.setBackground(Color.WHITE);
        this.text.setForeground(Color.BLUE);
        this.text.setCaretColor(Color.RED);

        this.text.addKeyListener(new KeyAdapter() {
            public void keyReleased(KeyEvent e) {
                if (popup.isShowing()) {
                    popup.setVisible(false);
                } else if (e.getKeyCode() == KeyEvent.VK_PERIOD) {
                    Point point = text.getCaret().getMagicCaretPosition();
                    if (point != null) {
                        popup.show(text, point.x, point.y);
                    }
                    text.requestFocus();
                }
            }
        });
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                PopupTipDemo demo = new PopupTipDemo();
                demo.setSize(400, 200);
                TWaverUtil.centerWindow(demo);
                demo.setVisible(true);
            }
        });
    }
}

In fact, in Demo of TWaver Java, QuickSearch (the well-encapsulated component--twaver.swing.TDropDownSelector) is equipped with the feature described above. Through the following several lines of codes in demo.DemoUtil can realize the drop-down effect. What you need to do is only to focus on the contents you want to show on the menu.

// create drop down selector
final TDropDownSelector selector = new TDropDownSelector(txtSearch, new JScrollPane(list)){
    public Dimension getSelectorSize(){
        int width = this.getSize().width;
        if(width < 200){
            width = 200;
        }
        return new Dimension(width, 320);
    }
};

To Test the Memory Usage of TWaver Java

We have already seen the high performance of TWaver Java, but what about its memory usage? What about it with different amounts of data? How does view component have effects on memory? We have tested the following amounts of data respectively:

• to only add elements into the DataBox
• to add elements into DataBox and show them on Network
• to add elements into the DataBox and show them on Tree
• to add elements into the DataBox and show them on Tree and Network

The following is the four situations of the memory usage of different number of elements. (x-axis: the number of nodes, unit: K; y-axis: the memory that elements take, unit: MB)

1. To only add elements into the DataBox:
   
2. To add elements into DataBox and show them on Network：
   
3. To add elements into the DataBox and show them on Tree：
   
4. To add elements into the DataBox and show them on Tree and Network:
   

We can see from the graphs above: the view components do have effects on the memory. But it is good that 100 thousand of nodes take only less than 500MB. During the process of the test, we find that system environment has had affected the results. (Here we have taken the average value.)

Bundled links in Flex

We have already introduced the link-bundles in TWaver Java and found that there are quite some functions therein. More powerful functions have been provided in link-bundles in TWaver Flex.
Now let's first see the similar functions offered in TWaver Java:

link.setStyle(Styles.LINK_BUNDLE_ENABLE,false); //to judge whether the link is in a link-bundle or not
link.setStyle(Styles.LINK_BUNDLE_EXPANDED,false);  //to set whether the link-bundle is expanded or not
link.setStyle(Styles.LINK_BUNDLE_GAP,10); //to set the gap between every two links in the link-bundle
link.setStyle(Styles.LINK_HANDLER_YOFFSET, -5); //to set the vertical offset when bundled
link.setStyle(Styles.LINK_HANDLER_XOFFSET, -5); //to set the horizontal offset when bundled

 What's more, the grouped link-bundles are available in TWaver Flex as follows:

link.setStyle(Styles.LINK_BUNDLE_INDEPENDENT,true); //to set whether the link is bundled independently
link.setStyle(Styles.LINK_BUNDLE_ID, 0);  //to set the index of the groups of link-bundles

More functions supplied in bundleHandler:

link.setStyle(Styles.LINK_HANDLER_POSITION, position); //to set the position of the link handler and the value of position can be obtained from Consts
link.setStyle(Styles.LINK_HANDLER_COLOR, 0xFF0000);  //to set the color of the texts in the link handler
link.setStyle(Styles.LINK_HANDLER_FILL, true); //whether the link handler has the background color
link.setStyle(Styles.LINK_HANDLER_FILL_COLOR, 0x00FFFF); //to set the background color in the link handler
link.setStyle(Styles.LINK_HANDLER_XOFFSET, -5);   //to set the horizontal offset of the link handler
link.setStyle(Styles.LINK_HANDLER_YOFFSET, -5);  //to set the vertical offset of the link handler

The label of BundleHandle can be set by linkHandlerFunction of network to implement the functions mentioned in the last article.

In addition, the label which is used to be double-clicked to expand the bundled links can be set as being gradient, bold, italic and underlined.

link.setStyle(Styles.LINK_HANDLER_GRADIENT,Consts.GRADIENT_LINEAR_EAST); //to set the gradient type of the background color in the link handler
link.setStyle(Styles.LINK_HANDLER_GRADIENT_COLOR,0xFF00FF); //to set the gradient color of the background in the link handler
link.setStyle(Styles.LINK_HANDLER_BOLD,true); //to set the text in the link handler as bold
link.setStyle(Styles.LINK_HANDLER_ITALIC,true); //to set the text in the link handler as italic
link.setStyle(Styles.LINK_HANDLER_UNDERLINE,true); //to set the text in the link handler to be underlined

There are functions on looped link different from those on link in TWaver Flex:

link.setStyle(Styles.LINK_LOOPED_GAP, 10); //to set the gap between every two looped links

link.setStyle(Styles.LINK_LOOPED_TYPE, type); //to set the style of the looped links

link.setStyle(Styles.LINK_LOOPED_DIRECTION, direction); //to set the direction of looped links