I currently have a combo where a user can choose between different heading options to apply to a text. The problem I'm having is that the selection listener gets triggered every time the user traverses through the list with arrow keys.
I found out that widgetDefaultSelected allows you to wait for a certain confirmation, oftentimes pressing the 'Enter' key, before the selection will be made.
public ComboBuilder add(String text, Consumer<TypedEvent> onSelect) {
widget.add(text);
final int index = widget.getItemCount() - 1;
widget.addSelectionListener(new SelectionAdapter(){
#Override
public void widgetDefaultSelected(SelectionEvent e){
if (widget.getSelectionIndex() == index) {
onSelect.accept(e);
}
}
});
return this;
}
This stalls out the selection but then now the user is having to hit 'Enter' twice or mouse click + 'Enter'. What is the proper way to be able to traverse through the Combo selection (with the keyboard) while not having to go through these extra steps upon selection?
Related
I'm trying to stop the tree from collapsing or expanding when the user double clicks a column on a tree. It should only be allowed if the user clicks on the first column.
See, if a user double clicks the checkbox on node2 world1, the tree expands or collapses. I don't want that to happen. My tree needs SWT.FULL_SELECTION to detect the clicks on each of the columns, so that's not the way to go.
My listener looks like this
tree.addTreeListener(new TreeListener() {
#Override
public void treeExpanded(TreeEvent e) {
TreeItem parent = (TreeItem) e.item;
Point p = new Point (e.x, e.y);
int column = CheckboxClickListener.getColumn(p,parent);
if (column > 0) {
e.doit = false;
}
}
#Override
public void treeCollapsed(TreeEvent e) {
TreeItem parent = (TreeItem) e.item;
Point p = new Point (e.x, e.y);
int column = CheckboxClickListener.getColumn(p,parent);
if (column != 0) {
e.doit = false;
}
}
});
Problem is, the mouse event that generated the click is not the same as the TreeEvent that expands the tree. Thus, the e.x and e.y are both zero, making my Point detection useless. Listening to the mouse event and maintaining the last x and y to check here in the TreeExpand event seems bug-prone since the user may also expand the tree using the keyboard (thus the x and y may not reflect the user action). I also considered adding a time constraint to check that but seems like a bad way to handle the issue.
How can I detect which mouse event triggered the expand event?
PS: e.doit=false does nothing, even outside the if condition, so help with stopping the tree from expanding/collapsing would be appreciated as well :)
Thank you!
I found someone saying this is a bug at this link http://www.eclipse.org/forums/index.php/t/257325/
The following code stops the tree from expanding on doubleclick but I'm not sure why or what are the side effects.
tree.addListener (SWT.MeasureItem, new Listener(){
#Override
public void handleEvent(Event event) {}
});
This stops the expanding when doubleclicking ANY column. Clicking on the small arrow at the left of the TreeItem still expands the tree (as it should).
How do I catch double click event in gxt tree grid?
I already try this from :
Click Handlers for Trees in GXT 3?
tree.getSelectionModel().setSelectionMode(SelectionMode.SINGLE);
tree.getSelectionModel().addSelectionHandler(new SelectionHandler<MenuView.MenuDto>() {
public void onSelection(SelectionEvent<MenuDto> event) {
MenuDto mnu = event.getSelectedItem();
Info.display("Tree Handler", mnu.getDescripcion());
}
});
But it only works for single click, not double click.
I want if user press double click, pop up will show.
Selection has specific meaning in this case - are you sure you want doubleclick to cause selection to happen, and only then you want to be notified?
Instead, look at grid.addRowDoubleClickHandler - your handler will be given the row index that was clicked, and you can then ask the store what item is in that row.
Relevant GXT Javadoc:
grid.addRowDoubleClickHandler(...)
RowDoubleClickEvent
This is the code, i only test to see info display :
tree.addRowDoubleClickHandler(new RowDoubleClickHandler() {
#Override
public void onRowDoubleClick(RowDoubleClickEvent event) {
Info.display("hello", "double click");
}
});
I have a panel just with a Jtextfield that only accept numbers. So, when I press enter will load a user profile. this is just to see his profile.
What I want: When I press ENTER again all the profile will be cleared, and when I press the numbers and press ENTER again and load the profile again and again...
My problem: I pressed enter and the profile is cleared (Ok all fine), but when I enter the number and press the ENTER, The numbers are cleared and nothing happens, it is like a loop in matriculaTxt.addKeyListener(new KeyAdapter() { ... }
Sorry for my bad English.
private void matriculaTxtActionPerformed(java.awt.event.ActionEvent evt)
{
String matricula = matriculaTxt.getText().trim();
if (!matricula.matches("[0-9]+")) {
matriculaTxt.setText("");
} else {
fc = new FrequenciaController();
matriculaTxt.setEditable(false);
matriculaTxt.requestFocus();
fc.checkinManual(Integer.parseInt(matricula));
}
// the problem is here.
matriculaTxt.addKeyListener(new KeyAdapter() {
public void keyPressed(KeyEvent evt) {
if (evt.getKeyCode() == KeyEvent.VK_ENTER) {
nomeTxt.setText("");
statusTxt.setText("");
imageLb.setIcon(null);
acessoLabel.setText("");
matriculaTxt.setText("");
observacaoTxt.setText("");
System.err.println("ENTER");
PendenciasTableModel ptm = new PendenciasTableModel();// vazio
pendenciasTabela.setModel(ptm);
matriculaTxt.setEditable(true);
matriculaTxt.requestFocus();
}
}
});
}
What I wanted to do was simple. The user types in the text field their numbers, pressing ENTER: their data are loaded. requestFocus() into the text field and it will not be editable anymore, because when I press Enter again the field will be editable but everything will be deleted, and so on.
First off, you should never use a KeyListener for this sort of thing. Consider instead using either a JFormattedTextField or using a DocumentFilter to prevent non-numeric entry. Next, you should use an ActionLIstener to have the JTextField accept and react to the user's pressing the Enter key.
Edit
You state:
my exact requirements is, when i press ENTER again all data will be cleaned for a new data be inserted.
Why not simply have in your JTextField's ActionLIstener:
#Override
public void actionPerformed(ActionEvent e) {
// get the text
JTextComponent textComp = (JTextComponent) e.getSource();
String text = textComp.getText();
// do what you want with text here
// clear the text
textComp.setText("");
}
Again, you should not use a KeyListener for any of this stuff.
Edit 2
If you want a multi-state action listener, one that reacts differently depending on the state of the program, then give it some if blocks to allow it to react to the state of the JTextField. If the field is empty, do one thing, if it has numbers, do another, if it has text, show a warning and clear it:
#Override
public void actionPerformed(ActionEvent e) {
// get the text
JTextComponent textComp = (JTextComponent) e.getSource();
String text = textComp.getText().trim(); // trim it to rid it of white space
if (text.isEmpty()) {
// code to show a profile
return; // to exit this method
}
// if we're here, the field is not empty
if (!text.matches("[0-9]+")) {
// show a warning message here
} else {
// numeric only data present
// do action for this state
}
// clear the text
textComp.setText("");
}
The key again is to not use a KeyListener, but rather to "listen" for the enter key press with the ActionListener only, but to react differently depending on the state of the program, here likely being depending on what content is present in the JTextField.
I think that your problem that the KeyListener it'll not trigger, it will not execute the code inside it, because whenever you press ENTER it will trigger the matriculaTxtActionPerformed then declared the KeyLister, so the ENTER will effect it.
Let 'x' be an item in the JList. When I click it for the first time, the event fires, when I click it again, the event does not fire. I have to click some other item and then come back to 'x'.
How can I fire the event repeatedly from 'x' without having to deal with other items.
This is my code:
public void valueChanged(ListSelectionEvent e) {
if (e.getValueIsAdjusting() == false) {
if (list.getSelectedIndex() == -1) {} else {
String clicked = (String)list.getSelectedValue();
//method to fire is here
}
}
updateDisplays();
}
The ListSelectionListener reflects changes to the lists selection, you could use a MouseListener instead...
For example...
MouseListener ml = new MouseAdapter() {
#Override
public void mouseClicked(MouseEvent evt) {
if (SwingUtilities.isLeftMouseButton(evt) && evt.getClickCount() == 1) {
if (list.getSelectedIndex() != -1) {
int index = list.locationToIndex(evt.getPoint());
System.out.println("You clicked item # " + index);
}
}
}
}
list.addMouseListener(ml);
You can add a MouseListener and watch for clicks. Note that a click that changes the selection will fire both the MouseListener and your ListSelectionListener.
Another option is to immediately clear the selection from your ListSelectionListener; that way the next click will reselect and retrigger, although you will lose the ability to navigate through items with the keyboard.
It seems like sort of an unusual UX decision, though, to assign significance to a click on an already selected item in a list.
Adding based on your question comments: If you go the MouseListener route, I recommend looking for double-clicks instead of single-clicks if the click is going to execute an action (especially if the action changes data and is not undoable). Also note that your ListSelectionListener will execute actions as you navigate through the list with the keyboard, which may not be what you intend.
If your commands in your history list are typed, you could also consider using a drop-down combo box for both command entry and the history list, where a selection from history fills in the command text but does not execute. You'd also have an opportunity to add auto-complete from command history.
Currently, I have a JList listen to list selection listener.
private void jList1ValueChanged(javax.swing.event.ListSelectionEvent evt) {
// When the user release the mouse button and completes the selection,
// getValueIsAdjusting() becomes false
if (evt.getValueIsAdjusting()) {
/*
In certain situation, I may want to prevent user from selecting other
than current selection. How can I do so?
*/
}
}
In certain situation, I may want to prevent user from selecting other than current selection. How can I do so?
It seems too late when I receive ListSelectionEvent. But, if I want to do it before ListSelectionEvent happen, I do not know that user is trying to select other.
Here is one of the senario.
The JList is contains list of project name.
So, whenever user select new list item, we need to turn the View, from current project, and display new project.
However, current project may be unsaved yet.
Hence, if current project unsaved yet, we will ask for user confirmation, "Save Project?" (Yes, No, Cancel)
When user select cancel, this means he want to cancel his "select to another project" action. He want to stick with current JList selection.
We will pop up the confirmation dialog box in jList1ValueChanged event handle.
But when we try to stick with current JList selection, it is already too late.
I've implemented this as follows for the same workflow use-case. While it works sufficiently for me, I do wish there was a simpler and more elegant approach where the selection event could be vetoed before proceeding. If I have time to investigate and figure that out I'll repost, but it might rank as a case where the return on investment isn't worth it (i.e. customizing Swing classes, handling lower level mouse/keyboard events directly, etc). Anyway what I'm doing currently is saving the last good 'validated' selection, and reverting back to it if the user cancels a future selection. It's admittedly not the prettiest solution, but it works:
// save the last good (i.e. validated) selection:
private ProjectClass lastSelectedProj;
// listing of available projects:
private JList list;
// true if current selected project has been modified without saving:
private boolean dirty;
list.addListSelectionListener(new ListSelectionListener() {
public void valueChanged(ListSelectionEvent evt) {
if (evt.getValueIsAdjusting()) return;
// first validate this selection, and give the user a chance to cancel.
// e.g. if selected project is dirty show save: yes/no/cancel dialog.
if (dirty) {
int choice = JOptionPane.showConfirmDialog(this,
"Save changes?",
"Unsaved changes",
JOptionPane.YES_NO_CANCEL_OPTION,
JOptionPane.WARNING_MESSAGE);
// if the user cancels the selection event revert to previous selection:
if (choice == JOptionPane.CANCEL_OPTION) {
dirty = false; // don't cause yet another prompt when reverting selection
list.setSelectedValue(lastSelectedProj, true);
dirty = true; // restore dirty state. not elegant, but it works.
return;
} else {
// handle YES and NO options
dirty = false;
}
}
// on a validated selection event:
lastSelectedProj = list.getSelectedValue();
// proceed to update views for the newly selected project...
}
}
I think you would need to override the setSelectionInterval(...) method of JList to do nothing under your special situations.
Handling it at the event level is too late as the event has already occured.
I would suggest that you implement a custom ListSelectionModel.
table.setSelectionModel(new DefaultListSelectionModel(){
#Override
public void setSelectionInterval(int index0, int index1) {
if (dragState==0 && index0==index1 && isSelectedIndex(index0)) {
// Deny all clicks that are one row & already selected
return;
} else {
super.setSelectionInterval(index0, index1);
}
}
});