JavaFX 2 Automatic Column Width

Question

I have a JavaFX 2 table that is displaying contact details for people, lets imagine there are three columns: first name, last name and email address. When my application starts it populates the table with several rows of data about the people already in the system.

The problem is that the column widths are all the same. Most of the time the first and last name is displayed in full but the email address is getting clipped. The user can double click the divider in the header to resize the column but that will become tedious quickly.

Once the table has been pre-populated I would like to programatically resize all the columns to display the data they contain but I can't figure out how to achieve this. I can see that I can call col.setPrefWidth(x) but that doesn't really help as I would have to guess the width.

Answer 1

Also, a very simple trick based on an AnchorPane will be a good solution.

We gonna wrap the TableView into a AnchorPane but also we gonna anchor the left and right side of the TableView like this:

AnchorPane wrapper = new AnchorPane();

AnchorPane.setRightAnchor(table, 10.0);
AnchorPane.setLeftAnchor(table, 10.0);
wrapper.getChildren().add(table);

This simple code will stretch the TableView in both directions (right and left) also, it will adjust whenever the scrollbar is added.

You can get an idea of how this works watching this animated gif.

Now you can resize the columns, adding these lines:

fnColumn.setMaxWidth( 1f * Integer.MAX_VALUE * 30 ); // 30% width
lnColumn.setMaxWidth( 1f * Integer.MAX_VALUE * 40 ); // 40% width
emColumn.setMaxWidth( 1f * Integer.MAX_VALUE * 30 ); // 30% width

Answer 2

After 3 years, finally I found the solution, javafx column in tableview auto fit size

import com.sun.javafx.scene.control.skin.TableViewSkin;
import javafx.scene.control.Skin;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

public class GUIUtils {
    private static Method columnToFitMethod;

    static {
        try {
            columnToFitMethod = TableViewSkin.class.getDeclaredMethod("resizeColumnToFitContent", TableColumn.class, int.class);
            columnToFitMethod.setAccessible(true);
        } catch (NoSuchMethodException e) {
            e.printStackTrace();
        }
    }

    public static void autoFitTable(TableView tableView) {
        tableView.getItems().addListener(new ListChangeListener<Object>() {
            @Override
            public void onChanged(Change<?> c) {
                for (Object column : tableView.getColumns()) {
                    try {
                        columnToFitMethod.invoke(tableView.getSkin(), column, -1);
                    } catch (IllegalAccessException | InvocationTargetException e) {
                        e.printStackTrace();
                    }
                }
            }
        });
    }
}