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ContentProposalAdapter prevent new line on select proposal

I use the ContentProposalAdapter to provide content assist to my StyledText fields. I wrote an adapter that implements IControlContentAdapter, IControlContentAdapter2 to support the StyledText. My problem is that, when I press return to insert the proposal the return key is inserted into the StyledText and after that the proposal is inserted.
Why are the UP and DOWN arrows not traversed, but the return key is.
How to prevent the return key from begin inserted into the StyledText field when used to select a proposal.

maybe the question is old, but as I googled and this Post nearly covered my problem, but without a solution, I thought to provide my solution I found now.
My Problem was exactly the same but the newline got inserted after the selected proposal.
Selecting the proposal via double click works just fine so I agreed with you that it´s probably the StyledTextWidget that gets notified about the Enter...
First I tried setPropagateKeys(false) on my ContentProposalAdapter, as the doc says it "indicates whether key events (including auto-activation characters) received by the content proposal popup should also be propagated to the adapted control when the proposal popup is open". But this does not work either.
What actually worked for me is the following:
I added an VerifyKeyListener to the StyledTextWidget and just filtered the Enter Event when the ProposalPopup is open. I thought that maybe wouldn´t work as the newline gets inserted after the proposal but on my program it works fine so it seems the closure of the proposal popup is done after the Enter Key is passed to the StyledTextWidget.
Heres the code:
styledText.addVerifyKeyListener(new VerifyKeyListener() {
#Override
public void verifyKey(VerifyEvent arg0) {
try {
KeyStroke k = KeyStroke.getInstance("Enter");
if(k.getNaturalKey() == arg0.keyCode && contentProposalAdapter.isProposalPopupOpen()) {
arg0.doit = false;
}
} catch (ParseException e) {
e.printStackTrace();
}
} });

I don't know how did you implement IControlContentAdapter, IControlContentAdapter2 in your code. Did you try this? I use that in my custom StyledText implementation. But all of them are SWT.SINGLE Text fields. I hope it may help you.

How to capture key events

All of the examples for key listeners I have been able to find deal with components other than the main panel such as a text box or Menu.
I know how to use setMnemonic to program Menu hotkeys but this method does not seem to be available and the link to the oracle keylistener tutorial is broken.
When I do a Right Click > Events > Key > KeyPressed on the main form I get the following but none of keys cause mainPanelKeyPressed.
What is the correct way to use the key events to trigger an action independent of the focus?
mainPanel.addKeyListener(new java.awt.event.KeyAdapter() {
public void keyPressed(java.awt.event.KeyEvent evt) {
mainPanelKeyPressed(evt);
}
});
private void mainPanelKeyPressed(java.awt.event.KeyEvent evt) {
// Added to help find the ID of each 'arrow' key
JOptionPane.showMessageDialog(null, "mainPanelKeyPressed");
}

What is the correct way to use the key events to trigger an action independent of the focus?
See: How to Use Key Bindings
Or use a JMenuBar with menus and menu items.

the focus is important. you may need to click around and experiment, and use component.requestFocusInWindow() to help.

IPhone password field in AWT/SWT?

I want to create a special Password Dialog for my eclipse product, which is used with an on screen keyboard.
It would be very nice, if i could use a component like the IPhone Password field. In this field, the added character is shown for a second and after the second it is converted into the '*' character for hiding the complete password.
Did a jar/library exists, this is implemented in AWT or SWT?
Edit:
I could trying to implement it from scratch (SWT), but for these i would have to create a very special and complicated KeyListener for the password Text component. I would have to catch the keyReleased event and set the characters manually into the field.
So far i was not able to find any libraries in the web. Suggestion how this can be implemented are welcome too.

This is not really a full answer, rather than a discussion starter and I don't know of any out-of-the-box widgets which can do that.
My first idea was to inheriting the swt Text widget and overriding setEchoChar et al., but after looking at the code this doesn't really seem feasible, because this method is merely a wrapper around:
OS.SendMessage (handle, OS.EM_SETPASSWORDCHAR, echo, 0);
If anyone would know the OS specific low-level implementation, that might be helpful.
Anyway, on to a different approach. I would avoid the KeyListener and use a ModifyListener on the Text-Widget.
void addModifyListener(ModifyListener listener)
You could then build a wrapper which catches the entered text using this listener, appends it to a locally held string/stringbuffer (or e.g. the Eclipse Preferencestore) and send a modified full text to the Text widget using setText(String s), replacing all characters except the last by an echo character (e.g. *).
myText.setText((s.substring(0, s.length()-1)).replaceAll("[\\s\\S]","*")+s.charAt(s.length()-1));
This is a bit of a kludge, but it should work.
The not so straightforward bit is the 1 second timing, without stalling the whole view...

Depending on what Jules said the following code is some kind of working.
The code is quick and fast and i would like to have a more thread safe solution.
originalString = new StringBuffer();
passwordField.addModifyListener(new ModifyListener() {
public void modifyText(ModifyEvent e) {
synchronized (passwordField) {
String s = passwordField.getText();
String newS = s.replaceAll("[\\s\\S]", "*");
if (newS.equals(s)) {
while (originalString.length() > s.length()) {
originalString = originalString.deleteCharAt(originalString.length() - 1);
}
usernameField.setText(originalString.toString());
return;
}
if (originalString.length() < s.length()) {
originalString.append(s.charAt(s.length() - 1));
}
try {
Thread.sleep(500);
} catch (InterruptedException e1) {
}
passwordField.setText(newS);
}
passwordField.redraw();
passwordField.setSelection(passwordField.getText().length());
}
});
Key Events are cached, so you can add more characters, also when the Thread is waiting.
Another Problem is the Cursor handling. the Cursor always moves to the first position, when you set the Text.
I think when this is working it is very near to the iphone solution.

SWT, Maintain default tab ordering when adding Key Listner

I've been creating a custom TabFolder extension that adds a key listener to allow quick tab switching using an ALT + # hotkey.
By adding the KeyAdapter to my TabFolder, the event handler works properly only when you have a tab header selected (in which case the ALT + ARROW_LEFT/ARROW_RIGHT also work.). I need this hot key to be active when any Widget with-in the TabFolder is active; however, it shouldn't be active if the selection is in a different tab folder or widget outside of a tab folder.
In an attempt to solve this, I wrote a simple recursive function to apply the key listener to all of the children of the tab folder:
public void applyQuickSwitchKeyBindings() {
removeKeyListener(ka);
addKeyListener(ka);
for(Control c: getChildren())
applyQuickSwitchKeyBindingsToChildren(c);
}
private void applyQuickSwitchKeyBindingsToChildren(Control c) {
if(c==null) return;
if(c instanceof Composite) {
Control[] controls = ((Composite)c).getChildren();
for(Control c2: controls)
applyQuickSwitchKeyBindingsToChildren(c2);
if(controls.length < 1) {
c.removeKeyListener(ka);
c.addKeyListener(ka);
}
}
}
Then i call the applyQuickSwitchKeyBindings() after I add the controls to each TabItem in the tab group.
The good news was that the quick switch hot key (ALT + #) worked great!
The bad news was that the original TAB ordering based on z-index is now gone. When you hit the SWT.TAB key you lose focus on your current text box and don't gain focus on anything else...
Questions:
1.) Can each control only have one KeyListener?
2.) Why is the original TAB traversal not working anymore?
Thanks in advance!

to 1) I'm pretty sure that more than one KeyListener is allowed.
to 2) I'm not sure, that depends on what you're doing in your KeyAdapter. Maybe you can post that too?
I just the tab order is broken somehow, you can reset ( or change ) it with a call to setTabList( Control[] ).
setTablList( new Control[] {
control1,
control2,
control3,
....
} );

So after more time learning and developing with SWT i've discovered my problem. When you add a listener it is applied to the widget/control you call the addXXXListener function on. So if that control is not active the listeners will not be fired.
The solution seems to be SWT's global Filter mechanism which allows you to add global application(Display) scope listeners.
Display.getCurrent().addFilter(SWT.keyPress, new KeyPressListener());
Pardon the incorrectness of this line, but if you google it you'll see what i mean.
I have also read to use this sparingly.

Hide certain actions from Swing's undo manager

I am trying to write a JTextPane which supports some sort of coloring: as the user is typing the text, I am running some code that colors the text according to a certain algorithm. This works well.
The problem is that the coloring operations is registered with the undo manager (a DefaultDocumentEvent with EventType.CHANGE). So when the user clicks undo the coloring disappears. Only at the second undo request the text itself is rolled back.
(Note that the coloring algorithm is somewhat slow so I cannot color the text as it is being inserted).
If I try to prevent the CHANGE events from reaching the undo manager I get an exception after several undo requests: this is because the document contents are not conforming to what the undoable-edit object expects.
Any ideas?

You could intercept the CHANGE edits and wrap each one in another UndoableEdit whose isSignificant() method returns false, before adding it to the UndoManager. Then each Undo command will undo the most recent INSERT or REMOVE edit, plus every CHANGE edit that occurred since then.
Ultimately, I think you'll find that the styling mechanism provided by JTextPane/StyledDocument/etc. is too limited for this kind of thing. It's slow, it uses too much memory, and it's based on the same Element tree that's used to keep track of the lexical structure of the document. It's okay (I guess) for applications in which the styles are applied by the user, like word processors, but not for a syntax highlighter that has to update the styles constantly as the user types.
There are several examples out there of syntax-highlighting editors based on custom implementations of the Swing JTextComponent, View and Document classes. Some, like JEdit, re-implement practically the whole javax.swing.text package, but I don't think you need to go that far.

How are you trying to prevent the CHANGE events from reaching the undo manager?
Can you not send the UndoManager a lastEdit().die() call immediately after the CHANGE is queued?

I can only assume how you are doing the text colouring. If you are doing it in the StyledDocuments change character attribute method you can get the undo listener and temporarily deregister it from the document for that operation and then once the colour change has finshed then you can reregister the listener.
Should be fine for what you are trying to do there.
hope that helps

I have just been through this problem. Here is my solution:
private class UndoManagerFix extends UndoManager {
private static final long serialVersionUID = 5335352180435980549L;
#Override
public synchronized void undo() throws CannotUndoException {
do {
UndoableEdit edit = editToBeUndone();
if (edit instanceof AbstractDocument.DefaultDocumentEvent) {
AbstractDocument.DefaultDocumentEvent event = (AbstractDocument.DefaultDocumentEvent) edit;
if (event.getType() == EventType.CHANGE) {
super.undo();
continue;
}
}
break;
} while (true);
super.undo();
}
#Override
public synchronized void redo() throws CannotRedoException {
super.redo();
int caretPosition = getCaretPosition();
do {
UndoableEdit edit = editToBeRedone();
if (edit instanceof AbstractDocument.DefaultDocumentEvent) {
AbstractDocument.DefaultDocumentEvent event = (AbstractDocument.DefaultDocumentEvent) edit;
if (event.getType() == EventType.CHANGE) {
super.redo();
continue;
}
}
break;
} while (true);
setCaretPosition(caretPosition);
}
}
It is an inner class in my custom JTextPane, so I can fix the caret position on redo.