Overview

Table is a WidgetGroup that sets the position and size of its children using a logical table, similar to HTML tables. Tables are intended to be used extensively in scene2d.ui to layout widgets, as they are easy to use and much more powerful than manually sizing and positioning widgets. Table-based layouts don’t rely on absolute positioning and therefore automatically adjust to different widget sizes and screen resolutions. TableLayout for libGDX (by the same author). TableLayout provides the same functionality as Table but for other UI toolkits (Swing, Android, etc).

• Quickstart
• Root table
• Debugging
• Adding cells
• Logical table
• Cell properties
• Expand
• Alignment
• Fill
• Widget size
• Padding
• Spacing
• Colspan
• Uniform
• Defaults
• Cell defaults
• Column defaults
• Row defaults
• Values
• Overlapping widgets
• Inserting cells
• Notes

  Quickstart

    Label nameLabel = new Label("Name:", skin);    TextField nameText = new TextField("", skin);    Label addressLabel = new Label("Address:", skin);    TextField addressText = new TextField("", skin);    Table table = new Table();    table.add(nameLabel);    table.add(nameText).width(100);    table.row();    table.add(addressLabel);    table.add(addressText).width(100);

  add method returns a Cell, which has methods to control layout. The table sizes and positions its children, so setting the width of the text fields to 100 is done on the table cell, not on the text fields themselves.

  Root table

  When doing UI layout, a UI widget does not set its own size. Instead, it provides a minimum, preferred, and maximum size. The widget’s parent uses its own size along with these hints to size the widget. Many layouts will use a single table at the root which has a fixed size, often the whole screen. Widgets and nested tables are added to the root table, resulting in a responsive layout that doesn’t rely on fixed positions or fixed sizes. setFillParent method can be used to easily size the root table to the stage (but should generally only be used on the root table):

    Table table = new Table();    table.setFillParent(true);    stage.addActor(table);

  Debugging

  Table can draw debug lines to visualize what is happening in the layout. It is enabled following way:

  table.setDebug(true); // turn on all debug lines (table, cell, and widget)

  Adding cells

  add method. This adds a cell to the current row. To move to the next row, call the row method.

    table.add(nameLabel);    table.add(nameText);    table.row();    table.add(addressLabel);    table.add(addressText);

  add method returns a Cell, which has properties that control the layout. Every method on the cell returns the cell, allowing calls to be chained.

    table.add(nameText).padLeft(10).width(100);

  Logical table

  The cells make up a logical table, but it is not sized to the table widget. The outer blue rectangle shows the size of the table widget. The inner blue rectangle shows the size of the logical table, which is aligned to center by default. The alignment can be changed using methods on the table. The table methods return the table, so can be chained just like the cell methods.

    table.right().bottom();

  Cell properties

  Expand

  cells will receive the extra space.

    table.add(nameLabel).expandX();    table.add(nameText).width(100);    table.row();    table.add(addressLabel);    table.add(addressText).width(100);

  The red lines show the cell bounds and the green lines show the widget bounds. Note that the left column has received all of the extra space in the x direction. Only one cell needs to have expand to cause the entire column or row to expand. If multiple columns expand, the extra space is distributed evenly.

    table.add(nameLabel).expandX();    table.add(nameText).width(100).expandX();    table.row();    table.add(addressLabel);    table.add(addressText).width(100);

  expandY method. The expand method causes expand to happen in both directions.

    table.add(nameLabel).expand();    table.add(nameText).width(100);    table.row();    table.add(addressLabel);    table.add(addressText).width(100);

  Alignment

  Similar to aligning the logical table, a widget can be aligned inside the cell.

    table.add(nameLabel).expand().bottom().right();    table.add(nameText).width(100).top();    table.row();    table.add(addressLabel);    table.add(addressText).width(100);

  Fill

  fill method causes a widget to be sized to the cell. Like expand, there are also fillX and fillY methods.

    table.add(nameLabel).expand().bottom().fillX();    table.add(nameText).width(100).top();    table.row();    table.add(addressLabel);    table.add(addressText).width(100);

  Note the red cell lines are drawn on top of the green widget lines.

  Widget size

  fill methods won’t make a widget larger than the widget’s maximum size. It is a common beginner’s mistake to attempt to size or position a widget in a table by setting the size on the widget. The table sizes and positions its children using their preferred, minimum, or maximum size, so the table will overwrite any size or position set previously. preferred, minimum, or maximum size on the cell containing the widget and your value will be used instead of the widget’s value.

    table.add(nameLabel);    table.add(nameText).minWidth(100);    table.row();    table.add(addressLabel);    table.add(addressText).prefWidth(999);

  prefWidth of 999 is larger than the table, so it is sized down to fit. width is a shortcut method for setting minWidth, prefWidth, and maxWidth to the same value. height is a shortcut method for setting minHeight, prefHeight, and maxHeight to the same value. The size method takes a width and a height and sets all six properties.

  Padding

  extra space around the edges of a cell.

    table.add(nameLabel);    table.add(nameText).width(100).padBottom(10);    table.row();    table.add(addressLabel);    table.add(addressText).width(100).pad(10);

  Note that padding between cells combines, so there are 20 pixels between the text fields. The debug lines don’t necessarily show which cell the padding comes from, since it is not important for the layout of the table. Padding can also be applied to the edges of the table.

    table.pad(10);

  Spacing

  spacing between cells does not combine, instead the larger of the two is used. Also, spacing is not applied at the edge of the table. Spacing makes it easy to have consistent space between cells, eg for forms.

    table.add(nameLabel);    table.add(nameText).width(100).spaceBottom(10);    table.row();    table.add(addressLabel);    table.add(addressText).width(100).space(10);

  Note that the spacing between cells doesn’t combine, so there are 10 pixels between the text fields. Also note that there is no spacing under the bottom text field because spacing isn’t applied around the edge of the table.

  Colspan

  A cell can span multiple columns.

    table.add(nameLabel);    table.add(nameText).width(100).spaceBottom(10);    table.row();    table.add(addressLabel).colspan(2);

  Note that there is no rowspan. To acheive this, use a nested table.

  Uniform

  uniform set to true will be the same size.

    table.add(nameLabel).uniform();    table.add(nameText).width(100).uniform();    table.row();    table.add(addressLabel);    table.add(addressText).width(100);

  Defaults

  Cell defaults

  defaults method on the table returns a cell whose properties are the defaults for all cells.

    table.defaults().width(100);    table.add(nameLabel);    table.add(nameText);    table.row();    table.add(addressLabel);    table.add(addressText);

  Column defaults

  columnDefaults method on the table returns a cell whose properties are the defaults for all cells in that column. Any properties set here will override the cell default properties. Columns are indexed starting at 0.

    table.columnDefaults(1).width(150);    table.add(nameLabel);    table.add(nameText);    table.row();    table.add(addressLabel);    table.add(addressText);

  Row defaults

  row method is called, it returns a cell whose properties are the defaults for all cells in that row. Any properties set here will override both the cell default properties and the column default properties. Note it is allowed to call row before any cells are added. This allows the first row to have row default properties.

    table.row().height(50);    table.add(nameLabel);    table.add(nameText);    table.row().height(100);    table.add(addressLabel);    table.add(addressText);

  Values

  Value instances. When numeric values are used, Value.Fixed is used. Value allows for more flexibility, eg to base a size or padding on another widget.

    table.add(nameLabel);    table.add(nameText).pad(new Value.Fixed(10));    table.row();    table.add(addressLabel).width(Value.percentWidth(0.33f));    table.add(addressText);

  Overlapping widgets

  Stack can be used.

  Inserting cells

  clearChildren to remove all children and cells, then add them all to the Table again. VerticalGroup or HorizontalGroup can be used.

  Notes

• Table#setRound(false) to change it.