htmlviewerhelpdialog.java

Java实例入门

/*
 * Copyright (c) 1996-2001 Borland Software Corporation. All Rights Reserved.
 *
 * This SOURCE CODE FILE, which has been provided by Borland Software as part
 * of an Borland Software product for use ONLY by licensed users of the product,
 * includes CONFIDENTIAL and PROPRIETARY information of Borland Software.
 *
 * USE OF THIS SOFTWARE IS GOVERNED BY THE TERMS AND CONDITIONS
 * OF THE LICENSE STATEMENT AND LIMITED WARRANTY FURNISHED WITH
 * THE PRODUCT.
 *
 * IN PARTICULAR, YOU WILL INDEMNIFY AND HOLD BORLAND SOFTWARE, ITS
 * RELATED COMPANIES AND ITS SUPPLIERS, HARMLESS FROM AND AGAINST ANY
 * CLAIMS OR LIABILITIES ARISING OUT OF THE USE, REPRODUCTION, OR
 * DISTRIBUTION OF YOUR PROGRAMS, INCLUDING ANY CLAIMS OR LIABILITIES
 * ARISING OUT OF OR RESULTING FROM THE USE, MODIFICATION, OR
 * DISTRIBUTION OF PROGRAMS OR FILES CREATED FROM, BASED ON, AND/OR
 * DERIVED FROM THIS SOURCE CODE FILE.
 */
//------------------------------------------------------------------------------
// Copyright (c) 1996-2001 Borland Software Corporation.  All Rights Reserved.
//------------------------------------------------------------------------------

package com.borland.samples.dbswing.htmlviewer;

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.net.*;
import javax.swing.*;

import com.borland.dbswing.*;
import com.borland.dx.dataset.*;
import com.borland.jbcl.control.*;

public class HtmlViewerHelpDialog extends JDialog {
  // Data Express
  TableDataSet urlTds = new TableDataSet();
  Column urlNodeIdCol = new Column();
  Column urlUrlCol = new Column();
  Column urlHtmlPageCol = new Column();

  // Visual components
  JSplitPane jSplitPane1 = new JSplitPane();
  JSplitPane jSplitPane2 = new JSplitPane();
  JdbNavTree urlNameTree = new JdbNavTree();
  JdbTable jdbTable1 = new JdbTable();
  JdbEditorPane jdbEditorPane1 = new JdbEditorPane();
  JdbStatusLabel statusBar = new JdbStatusLabel();

  // Layout
  JPanel dialogPanel = new JPanel();
  BorderLayout borderLayout1 = new BorderLayout();
  JScrollPane treeScrollPane = new JScrollPane();
  TableScrollPane tableScrollPane = new TableScrollPane();
  JScrollPane editorPaneScrollPane = new JScrollPane();

  // Data for tree nodes and URLs
  String protocol = "file:";
  String[][] nodeData =
    { { "<root>",                                           "/",                     ""                               },
      { "/",                                                "Help system overview",  "Overview.html"                  },
      { "/Help system overview",                            "Concepts",              "Concepts.html"                  },
      { "/Help system overview/Concepts",                   "Tree basics",           "Concepts_TreeBasics.html"       },
      { "/Help system overview/Concepts",                   "The user data object",  "Concepts_TreeDataObject.html"   },
      { "/Help system overview/Concepts",                   "JdbEditorPane",         "Concepts_JdbEditorPane.html"    },
      { "/Help system overview",                            "Building help",         "BuildingHelp.html"              },
      { "/Help system overview/Building help",              "JSplitPane",            "BuildingHelp_JSplitPane.html"   },
      { "/Help system overview/Building help",              "Scroll panes",          "BuildingHelp_ScrollPanes.html"  },
      { "/Help system overview/Building help",              "Loading the tree",      "BuildingHelp_LoadTree.html"     },
      { "/Help system overview",                            "Using help",            "UsingHelp.html"                 }};

  //Construct the dialog
  public HtmlViewerHelpDialog(Frame parent) {
  super(parent);
    enableEvents(AWTEvent.WINDOW_EVENT_MASK);
    try  {
      jbInit();
      setup();
    }
    catch(Exception e) {
      DBExceptionHandler.handleException(e);
    }
    pack();
  }

  //Component initialization
  private void jbInit() throws Exception  {
    this.setTitle("Sample Help Window");
    dialogPanel.setLayout(borderLayout1);

    // DataSet columns
    urlNodeIdCol.setColumnName("NodeId");
    urlNodeIdCol.setDataType(Variant.STRING);
    urlNodeIdCol.setCaption("Node ID");
    urlUrlCol.setColumnName("URL");
    urlUrlCol.setDataType(Variant.STRING);
    urlUrlCol.setCaption("URL");
    urlHtmlPageCol.setColumnName("HtmlPage");
    urlHtmlPageCol.setDataType(Variant.OBJECT);
    urlHtmlPageCol.setCaption("HTML Page");

    urlNameTree.setCellRenderer(new HtmlViewerTreeRenderer());
    urlNameTree.setRootVisible(false);
    urlNameTree.setDataSet(urlTds);

    jdbEditorPane1.setDataSet(urlTds);
    jdbEditorPane1.setEnableFileLoading(false);
    jdbEditorPane1.setEnableURLLoading(false);

    // See note for urlTds_updating() method
    jdbTable1.setDataSet(urlTds);

        urlTds.addEditListener(new com.borland.dx.dataset.EditAdapter() {

      public void updating(DataSet dataSet, ReadWriteRow newRow, ReadRow oldRow) throws Exception {
        //urlTds_updating(dataSet, newRow, oldRow);
      }
    });

    jSplitPane1.setOrientation(JSplitPane.VERTICAL_SPLIT);
    treeScrollPane.setMinimumSize(new Dimension(100, 100));
    treeScrollPane.setPreferredSize(new Dimension(175, 300));
    editorPaneScrollPane.setMinimumSize(new Dimension(200, 100));
    tableScrollPane.setMinimumSize(new Dimension(0, 0));
    this.getContentPane().add(dialogPanel, null);
    dialogPanel.add(statusBar, BorderLayout.SOUTH);
    dialogPanel.add(jSplitPane1, BorderLayout.CENTER);
    jSplitPane1.add(tableScrollPane, JSplitPane.RIGHT);
    jSplitPane1.add(jSplitPane2, JSplitPane.LEFT);
    tableScrollPane.getViewport().add(jdbTable1, null);
    jSplitPane2.add(editorPaneScrollPane, JSplitPane.RIGHT);
    jSplitPane2.add(treeScrollPane, JSplitPane.LEFT);
    treeScrollPane.getViewport().add(urlNameTree, null);
    editorPaneScrollPane.getViewport().add(jdbEditorPane1, null);

    urlTds.setColumns(new Column[] { urlNodeIdCol, urlUrlCol, urlHtmlPageCol });
    statusBar.setDataSet(urlTds);
  } // jbInit

  private void setup() {
    // Create a tree model from our data and assign it to our tree. Load the
    // data set of URLs; this leaves the data set open and at the first row.
    // Now that we're done navigating, connect the two so tree selection
    // navigates the data set. Also connect the editor pane to the data set
    // so navigation to a new data set row loads its html page.  We load the
    // first one manually because we don't do any navigation that would trigger
    // the load.
    urlNameTree.setModel(new TreeModelMaker(nodeData).getModel());
    loadDataSet();
    urlNameTree.setDataSet(urlTds);
    urlNameTree.setColumnName("NodeId");
    // Add listener here so we don't try to load pages when creating the table,
    // only afterwards, when user requests a page
    urlTds.addNavigationListener(new com.borland.dx.dataset.NavigationListener() {

      public void navigated(NavigationEvent e) {
        urlTds_navigated(e);
      }
    });

    jdbEditorPane1.setDataSet(urlTds);
    jdbEditorPane1.setColumnName("HTMLPage");
    jdbEditorPane1.setColumnNameURL("URL");

    // Load the first page
    try {
      jdbEditorPane1.setPageURL(urlTds.getString("URL"));
    }
    catch (DataSetException dse) {
      DBExceptionHandler.handleException(dse);
    }
  }

  // Don't load root because it's not visible in tree.  To get the effect of a
  // root, have a single child under the root. Leaves dataset open and at first row.
  private void loadDataSet() {
    try {
      urlTds.open();
      URL url = this.getClass().getResource("HtmlViewerHelpDialog.class");
      String path = protocol + url.getFile().substring(0, url.getFile().length() - "classes/com/borland/samples/dbswing/htmlviewer/HtmlViewerHelpDialog.class".length()) + "helpcontent/";
      for (int i = 1; i < nodeData.length; ++i) {
        urlTds.insertRow(false);
        urlTds.setString("NodeId", (nodeData[i][0].equals("/") ? "" : nodeData[i][0]) + "/" + nodeData[i][1]);
        System.out.println("HtmlViewerHelpDialog.loadDataSet() loading help content from: " + path + nodeData[i][2]);
        urlTds.setString("URL", path + nodeData[i][2]);
        urlTds.post();
      }
      urlTds.first();
    }
    catch (DataSetException dse) {
      DBExceptionHandler.handleException(dse);
    }
  }

  protected void processWindowEvent(WindowEvent e) {
    if(e.getID() == WindowEvent.WINDOW_CLOSING) {
      dispose();
    }
    super.processWindowEvent(e);
  }

  void urlTds_navigated(NavigationEvent e) {
    try {
      if (urlTds.isNull("HtmlPage")) {
        jdbEditorPane1.setPageURL(urlTds.getString("URL"));
      }
    }
    catch (DataSetException dse) {
      DBExceptionHandler.handleException(dse);
    }
  }

  // Our goal in this application is to use a data set as a cache for HTML pages.
  // However, reloading a cached page involves deserializing a complex serialized
  // object, and Swing is often unable to do this. As a workaround, we've disabled
  // caching by clearing the HTML column whenever a value is saved to it.  We still
  // bind our JdbEditorPane's to two columns, because we need to use the column containing
  // a URL to load our HTML pages.  For this application, performance is acceptable
  // without a caching because our help files are small and can be loaded quickly.
  // JdbEditorPane may not be useful for more demanding applications.
  void urlTds_updating(DataSet dataSet, ReadWriteRow newRow, ReadRow oldRow) throws Exception {
    if (oldRow.getObject("HtmlPage") != null) {
      newRow.setUnassignedNull("HtmlPage");
    }
  }

}