Hi. I was wondering if someone could help me here, i don't know where to start. I've got this project to complete and basically have to create a text editor. Its pretty much completed but just had to add the "open", "save", "cut", "copy", "paste" options. I just wanted to know if someone could help me with the few of the above commands - as i dont know where to place them in the code. Have copied 2 of the .java files that i need to add to. If someone can just lead me to the right path that would be great!!
----First is Editor.java---
/* * comp285 Editor class */ import java.awt.*; import java.awt.event.*; /** * * @author Ian A. Mason. * @see CenteredFrame * @see java.awt.Frame * @version 1.1 * @since 13/03/03 */
class Editor extends CenteredFrame { /** * A boolean flag used to turn on/off error messaging to System.err. * A static flag, accessed via the class, not an instance!! * This protected constant can be used by the other classes in this * application. You can turn it off once you think your program * is ready to ship! */ protected static final boolean VERBOSE = true; /** * The labels for the items in the file pulldown menu. * Static data, accessed via the class, not an instance!! * This protected constant can be used by the other classes in this * application. These are used by the EditorMenuHandler object to * decide which item has been selected. */ protected static final String[] fileLabels = { "Open", "Save", "Search", "Quit" }; /** * The labels for the items in the edit pulldown menu. * Static data, accessed via the class, not an instance!! * This protected constant can be used by the other classes in this * application. These are used by the EditorMenuHandler object to * decide which item has been selected. */ protected static final String[] editLabels = { "Cut", "Copy", "Paste"}; /** * The TextArea instance textArea is the little workhorse of the editor. * <em>Note that it is private, and must remain so!</em> Only the editor object * is permitted to talk to this object. * @see java.awt.TextArea * @see java.awt.TextComponent */ private final TextArea textArea = new TextArea("", 40, 80, TextArea.SCROLLBARS_BOTH); /** * The MenuBar instance menuBar is the toplevel widget at the top of the editor * that contains the pull down menus. <em>Note that it is private, and must * remain so! Only the editor object is permitted to talk to this object.</em> * @see java.awt.MenuBar */ private final MenuBar menuBar = new MenuBar(); /** * The file menu is the thing that one clicks on to pull down the menu items. * @see java.awt.Menu */ private final Menu fileMenu = new Menu("File"); /** * The items in the pull down file menu belong to this array. Its length is determined * by the static final array of file item labels. * @see java.awt.MenuItem */ private final MenuItem[] fileItem = new MenuItem[fileLabels.length]; /** * The edit menu is the thing that one clicks on to pull down the menu items. * @see java.awt.Menu */ private final Menu editMenu = new Menu("Edit"); /** * The items in the pull down edit menu belong to this array. Its length is determined * by the static final array of edit item labels. * @see java.awt.MenuItem */ private final MenuItem[] editItem = new MenuItem[editLabels.length]; /** * This is the name we use to refer to the object that handles the editors * events. Though we will not actually ever send it any messages, just merely * register it with Java as a listener to the appropriate events. * * @see EditorMenuHandler */ private EditorMenuHandler menuHandler; /** * An auxiliary procedure for initializing the pull down menus. It eliminates * a small amount of code duplication. */ private void initMenu(MenuItem[] menuItems, String[] menuLabels, Menu menu, EditorMenuHandler menuHandler, MenuBar menuBar){ for(int i = 0; i < menuItems.length; i++){ menuItems = new MenuItem(menuLabels); menu.add(menuItems); menuItems.addActionListener(menuHandler); } menuBar.add(menu); } /** * The private Editor object constructor is where most of the work gets done. * Making the CenteredFrame part using the super construct (i.e by calling the * CenteredFrame constructor. It also makes the other * important toplevel object, the menuHandler. * It also must make * all the awt components that are part of the editor: the text area, the * pull down menus, and register the menuHandler with the widgets that it * needs to listen to (the events that they generate). */ private Editor(){ super("Text Editor"); menuHandler = new EditorMenuHandler(this); textArea.setFont(new Font("SansSerif", Font.PLAIN, 15)); setMenuBar(menuBar); // make the pull down file menu initMenu(fileItem,fileLabels,fileMenu,menuHandler,menuBar); // make the pull down edit menu initMenu(editItem,editLabels,editMenu,menuHandler,menuBar); //set the layout manager to be a BorderLayout object setLayout(new BorderLayout()); //put the textArea in the center add(textArea, BorderLayout.CENTER); //validate the layout validate(); //make the editor visible setVisible(true); } /** * The main method that creates an Editor instance, and * thus starts the whole kit and kaboodle. */ public static void main(String[] args){ Editor editor = new Editor(); //the reason this doesn't exit immediately is because //this is actually a multithreaded application. The other //thread sitting in the background is the <em>event handler thread</em> } }
/** * This method opens a file on the local file system and returns its contents * as a String */ protected String openFile(String filename) {
results = in_file.getAbsolutePath() + " is too large for this application to open."; fileOpened = false;
}
return results;
}
-------The second is Edithandler.java----
/* * comp285 EditorMenuHandler class */ import java.awt.*; import java.awt.event.*; /** * The EditorMenuHandler that handles the events generated by the * menu of the Editor class. * @author Ian A. Mason. * @version 1.1 * @since 13/03/03 * @see java.awt.event.ActionListener * @see java.awt.event.ItemListener */ class EditorMenuHandler implements ActionListener, ItemListener { /** * This is the name of the Editor instance whose events this EditorMenuHandler instance is * listening to. It will need to ask it to perform certain tasks according to what * type of event it hears has happened. */ private Editor editor; /** * This constructs a EditorMenuHandler instance who handles the events of the * particular Editor instance. * */ protected EditorMenuHandler(Editor editor){ this.editor = editor; } /** * This here is where all the events of interest get handled. It will be here * that you will have to ask the editor to do the appropriate things. * @see java.awt.event.ActionListener */ public void actionPerformed(ActionEvent ae){ FileDialog filedialog; final SearchDialog searchDialog; String arg = (String)ae.getActionCommand(); // the Open ... case if(arg.equals(Editor.fileLabels[0])){ if(Editor.VERBOSE) System.err.println(Editor.fileLabels[0] + " has been selected"); filedialog = new FileDialog(editor, "Open File Dialog", FileDialog.LOAD); filedialog.show(); if(Editor.VERBOSE){ System.err.println("Exited filedialog.setVisible(true);"); System.err.println("Open file = " + filedialog.getFile()); System.err.println("Open directory = " + filedialog.getDirectory()); } } //the Save ... case if(arg.equals(Editor.fileLabels[1])){ if(Editor.VERBOSE) System.err.println(Editor.fileLabels[1] + " has been selected"); filedialog = new FileDialog(editor, "Save File Dialog", FileDialog.SAVE); filedialog.show(); if(Editor.VERBOSE){ System.err.println("Exited filedialog.setVisible(true);"); System.err.println("Save file = " + filedialog.getFile()); System.err.println("Save directory = " + filedialog.getDirectory()); } } //the Search ... case if(arg.equals(Editor.fileLabels[2])){ if(Editor.VERBOSE) System.err.println(Editor.fileLabels[2] + " has been selected"); searchDialog = new SearchDialog(editor); searchDialog.show(); if(Editor.VERBOSE) System.err.println("searchDialog.show(); has exited"); } //the Quit ... case if(arg.equals(Editor.fileLabels[3])){ if(Editor.VERBOSE) System.err.println(Editor.fileLabels[3] + " has been selected"); System.exit(0);
} //the Cut case if(arg.equals(Editor.editLabels[0])){ if(Editor.VERBOSE) System.err.println(Editor.editLabels[0] + " has been selected"); } //the Copy case if(arg.equals(Editor.editLabels[1])){ if(Editor.VERBOSE) System.err.println(Editor.editLabels[1] + " has been selected"); } //the Paste case if(arg.equals(Editor.editLabels[2])){ if(Editor.VERBOSE) System.err.println(Editor.editLabels[2] + " has been selected"); } } /** * This needs to be here since we need to implement the ItemListener * interface * @see java.awt.event.ItemListener */ public void itemStateChanged(ItemEvent ie){ //shouldn't need to do anything here. } }
Clipboard myclipboard = Toolkit.getDefaultToolkit().getSystemClipboard();
/** cut deletes selected text and stores the text into a string variable
*/
publicvoid cut(){
selectedtext = textArea.getSelectedText();
if (selectedtext != null){
StringSelection clipboardstring = new StringSelection(selectedtext);
myclipboard.setContents(clipboardstring,clipboardstring);
int startmark = textArea.getSelectionStart();
int endmark = textArea.getSelectionEnd();
textArea.replaceRange("",startmark,endmark);
}
}
/** copy() stores the selected text into a string variable
*/
publicvoid copy(){
selectedtext = textArea.getSelectedText();
if (selectedtext != null){
StringSelection clipboardstring = new StringSelection(selectedtext);
myclipboard.setContents(clipboardstring,clipboardstring);
}
}
/** paste() inserts the string stored from copy or cut at
* the current caret position
*/
publicvoid paste(){
Transferable clipboarddata = myclipboard.getContents(this);
try{
selectedtext = (String) clipboarddata.getTransferData(DataFlavor.stringFlavor);
}catch(Exception e){
System.err.println("Exception: " + e.getMessage());
}
textArea.insert(selectedtext,textArea.getCaretPosition());
}
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