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How to get Values from the JFX Table

I need to get all values from JFX Table View. Tell me to way for that. it's very important to me. below has that table.

If you want to get all items in the TableView you can use the getItems method. Otherwise if you want only the selected data, you can use a SelectionModel to get the selected item.

JavaFx with scenebuilder-which container or controls should I use for bus seat structure?

Bus Seat Structure
I need to implement a bus structure which will be generated using number of row and column given, I used a scrollpan as the structure may grow. Each seat is needed to be selected by user. I know I have to generate a matrix, But how can I design the UI that will represent the matrix, each cell will be a button.

You could use a TableView for this. You can create the columns as you like, add a style to it to fit your needs and perhaps add an empty column in the middle to achieve the same as in your picture. Here is also a good tutorial on the TableView.
You can also add columns to other columns. So in your example picture, you could add a "door" column which has a "left" and "right" column.

Dynamic columns for JTreeTable

I am building a JTreeTable. I found some starter code and have come pretty far. In the end my goal is to be able to have different data at different levels like a hierarchical list.
Currently, I have it working with data at different levels. However, I am running up against a wall when it comes to changing the columns as a next goal. From where I currently stand I have 3 more milestones:
Show different set of columns for different levels
Ability to adjust column widths for different levels
Ensure the JTree part of the table always stays to left
I am getting close to closing out this task but again stuck at the first of these 3.
Since creating a JTreeTable is complex, the minimum example leverages several class listed below in the image:
I am happy to post the code to any of those classes but I also did not want clog the question with useless code. First let me show the functionality I want.
The first image is when the top level is selected and the second image is when the second level is selected. Notice how the columns are different. That is what I want to happen in my application.
Top level selected:
Second level selected:
So one way I tried to solve this problem, is when the list selection is changed inside this section of code:
ListSelectionListener listener = (ListSelectionEvent e) -> {
TreeTableModelAdapter adapter = (TreeTableModelAdapter) JTreeTable.this.getModel();
//Need to see why this breaks.
JTreeTable.this.getTableHeader().setColumnModel(adapter.getColumnModel());
};
this.getSelectionModel().addListSelectionListener(listener);
This code is in the initialization of the JTreeTable. I have tried setting the column model on both the TableHeader and the table as well. Below is what happens then when I select a row:
The columns just disappear on me. The creation of the column model is happening in the TreeTableModelAdapter class with the following method:
public TableColumnModel getColumnModel(){
DefaultTableColumnModel model = new DefaultTableColumnModel();
for(int i=0;i<getColumnCount();i++){
TableColumn column = new TableColumn();
column.setIdentifier(getColumnName(i));
model.addColumn(column);
}
return model;
}
Any direction would be very helpful. Again happy to post any code you think could be helpful to answer the question. Just put a comment in and I will add it right away.

I will add the milestones as I find them in case this helps others, but for now this question is answered.
Milestone 1
I was actually able to solve the first milestone. The key is to trigger the creation of the columns of the column model, not to create a new column model. Below is the code for when the row selection is changed:
//Change columns depending on row
ListSelectionListener listener = (ListSelectionEvent e) -> {
createDefaultColumnsFromModel();
};
this.getSelectionModel().addListSelectionListener(listener);
This code creates the columns based on the row selected in the JTree part of the JTreeTable. The TreeTableModelAdapter implements the getColumnCount() and getColumnName() methods by also passing the selected row in the JTree to the JTreeTableModel so that the columns and their names are dynamically retrieved based on a particular node in the JTree. The key for this for me was trigger those to be called again to update the JTreeTable.
Milestone 2
Adjusting column widths based on the data level proved to be much more difficult than I had originally anticipated. In order to retain the cells state when the column model changed I had to disconnect the painting of the cells from it. This is a hairy process because this is done inside BasicTableUI and the method that gets the rectangle of the cell is private. So I had to subclass it, overload the paint() method and create my own methods that get called inside the paint method. There was a lot of copy pasting so that I could call normally private methods. I just renamed them and referenced these methods instead. The way the ui class was designed did not make it very flexible. Below is 2 images where I am selecting different levels and the columns are obviously different widths at different levels.
Milestone 3
I was able to make this work by keeping track of the view in the model. This seems very dirty to me as the model should separated from the view. Since the tree column's class is unique, I just returned the right class if that column was the first in the view.
The one problem I have with this technique is that I get unexpected behavior where the value returned is not consistent. I attempted to resolve this by overriding JTree.covertValueToText(). Since a JTree only expects 1 value and depending on the sequence of columns in the view this value could change. So in overriding this method I check the stored index for the JTree column's value. Again this causes the unexpected behavior. I will update the post if I find the fix.

When to use convertRowIndexToModel

I have some JDialogs displaying JTables.
When the header columns are clicked a sort occurs on that column.
My question is : how can I know when a column header has been clicked and thus made a sort active.
When the sort is active, I know I should user the .convertRowIndexToModel method.
But how do I detect that a column is sorting in order not to mess the correct index if no sort is active?

Generally speaking, you should ALWAYS uses the convertRowIndexToModel when you take an index value from the view (JTable) and try and look up some value within the model. The JTable does this automatically when you use it's methods, but incase you're not, you need to take care of it yourself.
There's no need to know if the view is sorted or not...
If you "really" want to know when a table is sorted, you could attach a RowSorterListener to the TableRowSorter used by the table.
You could also use the TableRowSorter#getSortKeys to see which columns are included in the sort...

I have used it for my selection table. When the auto order is activated (setAutoCreateRowSorter(true))
the indices of the model table and the visual change, so you have to tell it to look for it within the model with respect to the one you are seeing.
((CustomTable)form.getAvailListView().getModel()).data.get(form.getListView().convertRowIndexToModel(i))

How to Mirror Edits across a Table Cell and Text Field

The desired behavior is akin to the mirrored text editing field provided in Excel when a given cell is selected, allowing more space to view the contents of the cell. I have a JTable with 5 columns and n rows. Column 2 holds expressions that can be arbitrarily long, thus I'd like to provide a separate JTextField to work with for editing the contents of the expression cell per row. The other fields are directly editable in the table. When the user clicks on a field in column 2, however, I want to send them to the text field. Any contents preexisting in the cell should be appear in the text field and additional edits in the text field should be mirrored in the table cell. Likewise, if someone double-clicks on the cell and edits it directly, I want those changes reflected in the text field. Thus, the user can choose to edit in either space and both are updated. Ideally, they are updated per keystroke, but update upon hitting return is acceptable.
So, far I've got the JTable, TableModel, TableModelListener, JTextField, ListSelectionListener, and AbstractAction, working together to provide most of the functionality described above. I'm missing the reflection of direct table cell edits to the text field and per-keystoke updates.
Are their ideas on how best to construct this behavior?

Well, if you want to get data from the table to the cell then you add the code to your TableModel's setValueAt() function, which should run when the user changes the content in an editable cell. I don't think that will update per-keystroke though.
If you want to move data from the textbox to the table cell use code like this
myJTextField.getDocument().addDocumentListener(new MyDocumentListener());
Where MyDocumentListener is an implementation of the javax.swing.event.DocumentListener interface
That will get you per-keystroke updates from the box to the table. But for the other way around it's a bit trickier.
There are two ways you might be able to go about doing it
1) Add a key listener to the table, and when the user starts typing check to see what table element is active, and intercept keystrokes as they type. That's kind of messy, though.
2) Another option might be to try to grab or replace the component that the table is using to actually let the user make the changes. I think that JTable actually allows you to change the editor component if you dig around.