I made simple listview in javafx. If I press a key, loaded the data from database to list from like query. Now I want to select the 1st item in list view at key released. I try to do this from listview.getselectionmodel ().selectfirst () method. It select the 1st item as temporary. If I want to move up or down on the list, I happen to give a mouse click to list and then I can move up or down from arrow keys. But I don't want this manner. I want, if I give key released,the data loaded and that moment i can up or down on listview from arrow keys. What should I do? Please help me
To move focus to your ListView, call requestFocus().
// in your handler
listView.getItems().addAll(Arrays.asList("item1", "item2", "item3"));
listView.getSelectionModel().selectFirst();
Platform.runLater(listView::requestFocus);
Focused ListView will accepts key operations immediately.
Related
The case:
I have Activities as datamodel.
I have set Activities to have many-to-many relationship with themselves to represent a Parent / Child relationship.
I have set up an accordion widget. Each row of the accordion contain basic data about the Activity record + some buttons.
I have set one of the button's onClick functions to open a popup, which allows me to edit the Activity detail in a form.
When I click a different record from the same accordion, the form from the popup reflects the data in the selected record.
The problem:
I have nested accordions which represent the "Child" Activities of the Parent Activity.
I have also added a similar button, which opens a popup. I can open the popup, which targets the child records, but cannot make it open the specific record, from which I pressed the button.
So the popup open by default on the first child.
Please help - how can I make the popup change naturally to reflect the datasource / selected record of even nested datasources?
What I tried:
In order to try and make to popup work I have tried to set the datasource based on the relationship:
Activities: Sub_Activities(relation)
This works to the extent of showing the related items, but popup content does not dynamically change on clicking a different child record or clicking the button from a different child record.
In both cases what is shown is the first child record.
What I understand is that you have a set up in which you click a button and a popup shows. The popup should let you view/edit the record referenced in the row where the button is. If that is the case, then probably you already have almost everything setup for the next thing to work. First, add a string custom property to the popup and name it selectedKey. Then, on the onClick event of the button that opens the popup, add something like this:
var key = widget.datasource.item._key;
app.popups.MYPOPUP.properties.selectedKey = key;
app.popups.MYPOPUP.visible = true;
Now, go to the popup content and add the following on the onAttach event handler:
var key = widget.root.properties.selectedKey;
widget.datasource.selectKey(key);
This is the general idea of how to make it work; However, in order for it to work, your datsources in the widgets should be properly set up. Good luck!
I start with the question and then describe the problem more in detail:
Question:
Is there a way to receive events from the listview of a JavaFx ComboBox directly (ComboBox consists of a listview and a textfield as far as I understand)? I would like to find out which element of the list has been clicked by mouse or which element was selected when the user pressed enter on the keyboard (after navigating with Up/Down Arrows in the list). I therefore need to receive the mouse click event or the keypress event on the listview, but all I can get so far are events on the combobox itself which turned out to be only changes in the textfield of the combobox.
Detailed problem description:
I have a JavaFx Application with a combobox where the idea is that the value is directly added to another list when the user clicks on an entry in the combobox list (when the popup of the combobox is open). Additionally, when the user navigates in the combobox list with the arrow keys on the keyboard and he presses enter, the currently selected value should be taken and added to the other list. However so far I have not found out how I can implement this feature with the standard JavaFx combobox.
Tried:
The first solution I tried was to add a change listener on the combobox's valueProperty (this is the value that is displayed in the textfield when the popup is closed). So when the user clicks on a listentry, the popup closes and the clicked entry is put into the value field, changes the value and therefore fires my change listener. This worked well with the mouse, but keyboard navigation did not work correctly because everytime the user navigates down or up on the list, the value field of the combobox is updated with the currently selected listentry and therefore fires my changelistener every time (which in turn adds the value to my other list, while it should only be added on enter keypress).
The next solution was to not add a listener to the valueProperty, but to the showingProperty. Everytime the combobox popup closes, the current value of the value field is taken and added to the other list. This works again well with the mouse, but still has issues with keyboard navigation. While it now correctly handles up/down navigation in the list and enter keypresses, the problem is now when you try to cancel the selection. When you press escape, the value is taken as well and added to the other list like you would have pressed enter. The problem with this approach is that I cannot find out with which keypress the popup has been closed.
So the next idea I had is to add an event filter to the combobox itself with the addEventFilter Method of the ComboBox with code similar to the following (also proposed here StackOverflow):
ComboBox comboBox = new ComboBox();
comboBox.addEventFilter(KeyEvent.KEY_PRESSED, (event) -> {
// do stuff
});
But the event filter never gets called when the combobox popup is open. It is only called when the popup is closed, which leads me to the assumption that the event is consumed by the listview. So the only solution to the problem seems to be to somehow capture the events from the listview itself. And that leads back to the question at the beginning of this post. Sorry for the long explanation.:-)
Came across this question while looking for something else. It touches on something I've worked on before so assuming I understand what you're trying to accomplish and also that this is still relevant here are a couple of ideas.
To keep the other list (list #2) in sync with the combo box for mouse clicks try:
A ChangeListener on the selectedItem property for the combo box's selectionModel. Clicking an item in the popup (drop-down) list view will change the selectedItem value and close the Window that 'owns' the list view, or
An event handler to the combo box for the event type ComboBoxBase.ON_HIDDEN which gets fired when the list view closes (or better said 'becomes hidden').
The ChangeListener may be problematic inasmuch as the selection models for the combo box and the list view are linked at a low level, so that changes to the selectedItem value for the list view which will be triggered when navigating with key strokes will necessarily be handled by the ChangeListener. Since you want to sync the combo box and list #2 only when the ENTER key is pressed, this will probably not work. But that still leaves the event handler idea to try.
As for ENTER key press, you need to get a handle for the list view itself, and then add whatever behavior (listeners/event handlers) as needed. You do this by getting the skin for the combo box, which should be an instance of ComboBoxListViewSkin, and then get the list view by invoking the getPopupContent() method for the skin; it returns the popup list view as a Node so you'll to recast the returned value but no big deal.
Hope this helps.
The idea of the below code is that ListView is created once the combobox is loaded in the JavaFX scene. Therefore, we add a listener on the combobox to check when it appears on the scene, and then through "lookup" method we get its listview and add a listener to it.
In the example, I have set a MouseEvent listener but you can easily adjust it for keys as well.
private EventHandler<MouseEvent> cboxMouseEventHandler;
private void initComboBox() {
ComboBox<String> comboBox = new ComboBox<String>();
comboBox.getItems().add("Item 1");
comboBox.getItems().add("Item 2");
comboBox.getItems().add("Item 3");
comboBox.sceneProperty().addListener((a,oldScene,newScene) -> {
if(newScene == null || cboxMouseEventHandler != null)
return;
ListView<?> listView = (ListView<?>) comboBox.lookup(".list-view");
if(listView != null) {
cboxMouseEventHandler = (e) -> {
Platform.runLater(()-> {
String selectedValue = (String) listView.getSelectionModel().getSelectedItem();
if(selectedValue.equals("Item 1"))
System.out.println("Item 1 clicked");
});
}; // cboxMouseEventHandler
listView.addEventFilter(MouseEvent.MOUSE_PRESSED, cboxMouseEventHandler);
} // if
});
} // initComboBox
In my application, I have one tableview of items, and a side-panel "preview":ing the latest selected item.
I want clicking on an item to change the selection, and double-clicking to cause a "run"-action to be performed. More specifically, I want the "run"-action (including key-navigation and pressing enter) to be bound to the "activation" of the item in the table-row.
My problem is; single-clicks does not only change the selection, but fires the "activated" signal on the item. I would like to tweak it such that:
Navigation Keys, Single Mouse Click: Selection-change, update preview-panel
Enter Key, Double Mouse Click: Activate/run/open action triggered.
Is there a nice clean way to do it, or are overriding the onclick/doubleclick events my best option? Or is there some other tabular list-widget better suiting my needs?
I would connect the slot for the preview action to the currentChanged() signal of the table view's selectionModel(). This covers single clicks and key navigation.
Then there's two options for the double clicks and Enter key presses:
Subclass your tableview, override doubleClickEvent() and keyPressEvent() and fire your custom signal in there, with maybe the model index or something else as an argument. Then just connect your run method to your own signal as you have full control over when it is fired.
If you don't want to subclass, you can use the installEventFilter() mechanism.
Either I'm getting your approach wrong or I'm too tired, but if you want to trigger a run event you should avoid the activated signal completely. Set the signal slot mechanism so that your double click and Enter key press event trigger your run() function, and then the single click/nav buttons should trigger the 'activated' slot which will return your index in the tableview.
I'm pretty certain Qt wants you to be explicit about which signal points to which slot or it'll ignore it or point to a default.
I have a list control and i want the user to be able to select many items at a time. Thus I want it to act that if the control key is pressed while he is clicking. Eg if he clicks on a selected row it should become unselected and if he clicks on a unselected row it should become selected.
Do you have any idea how to do this?
Thanks,
Dennis
If you want to follow standard UI Precedent; then set allowMultipleSelection to true and teach your users to use the control and/or shift button to select multiple items.
If you want to select multiple items without having the using press the shift or control button you'll have to extend the List class. I did a sample a while ago using the DataGrid:
http://www.flextras.com/blog/index.cfm/2009/7/23/Flextras-Friday-Lunch--Episode-22--07032009--Auto-Select-DataGrid
http://www.flextras.com/labs/AutoSelectDataGrid/
http://www.flextras.com/labs/AutoSelectDataGrid/srcview/index.html
You can probably use the same technique with a List. But, I don't recommend this approach.
I just want to clarify, weather the feature is present or not in Qt.
The scenario is like this,
I have a list view with items, I want to place the icon to the listview when the item is selected.
The selection I mean is, first time when I click item should be selected, next time if I click the same item then it should display some icon. Please note
It is not the double click. again if do select some other item same feature should continue
So is there any feature which handles this feature by default, any property or flag which I need to set to listview to behave like this or manual implementation
Is required for this.
No problem (: Now I understand what you mean... So if you click on an item it should be selected (for example highlighted in blue) and then when you click on this item again, an icon should be displayed.
I can't think of a regualar way to do this, there is no such flag or something.
The easiest way I can think of would be to store the index in a QList when you select it. And when you deselect it, you delete the index from the list. SO, when you click on an item you can check if it is in that list and if so you can display your icon.
Another way would be to create your own type of QModelIndex. Everytime, this index is selected, you set a bool like is_already_selected on true. When clicking on this item again you check this bool and then decide whether an icon should be displayed or not.
For further information, see: QListView, QAbstractItemView::currentIndex, QModelIndex