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package javafx.scene.layout;

import static javafx.scene.layout.Region.USE_COMPUTED_SIZE;
import static javafx.scene.layout.Region.USE_PREF_SIZE;
import javafx.beans.property.BooleanProperty;
import javafx.beans.property.BooleanPropertyBase;
import javafx.beans.property.DoubleProperty;
import javafx.beans.property.DoublePropertyBase;
import javafx.beans.property.ObjectProperty;
import javafx.beans.property.ObjectPropertyBase;
import javafx.geometry.HPos;



Defines optional layout constraints for a column in a GridPane. If a ColumnConstraints object is added for a column in a gridpane, the gridpane will use those constraint values when computing the column's width and layout. 

For example, to create a GridPane with 5 columns 100 pixels wide:


    GridPane gridpane = new GridPane();
    for (int i = 0; i < 5; i++) {
        ColumnConstraints column = new ColumnConstraints(100);
        gridpane.getColumnConstraints().add(column);
    }


Or, to create a GridPane where columns take 25%, 50%, 25% of its width:


    GridPane gridpane = new GridPane();
    ColumnConstraints col1 = new ColumnConstraints();
    col1.setPercentWidth(25);
    ColumnConstraints col2 = new ColumnConstraints();
    col2.setPercentWidth(50);
    ColumnConstraints col3 = new ColumnConstraints();
    col3.setPercentWidth(25);
    gridpane.getColumnConstraints().addAll(col1,col2,col3);


Note that adding an empty ColumnConstraints object has the effect of not setting
any constraints, leaving the GridPane to compute the column's layout based
solely on its content's size preferences and constraints.

Since:JavaFX 2.0
/**
 * Defines optional layout constraints for a column in a {@link GridPane}.
 * If a ColumnConstraints object is added for a column in a gridpane, the gridpane
 * will use those constraint values when computing the column's width and layout.
 * <p>
 * For example, to create a GridPane with 5 columns 100 pixels wide:
 * <pre>{@code
 *     GridPane gridpane = new GridPane();
 *     for (int i = 0; i < 5; i++) {
 *         ColumnConstraints column = new ColumnConstraints(100);
 *         gridpane.getColumnConstraints().add(column);
 *     }
 * }</pre>
 * Or, to create a GridPane where columns take 25%, 50%, 25% of its width:
 * <pre>{@code
 *     GridPane gridpane = new GridPane();
 *     ColumnConstraints col1 = new ColumnConstraints();
 *     col1.setPercentWidth(25);
 *     ColumnConstraints col2 = new ColumnConstraints();
 *     col2.setPercentWidth(50);
 *     ColumnConstraints col3 = new ColumnConstraints();
 *     col3.setPercentWidth(25);
 *     gridpane.getColumnConstraints().addAll(col1,col2,col3);
 * }</pre>
 *
 * Note that adding an empty ColumnConstraints object has the effect of not setting
 * any constraints, leaving the GridPane to compute the column's layout based
 * solely on its content's size preferences and constraints.
 *
 * @since JavaFX 2.0
 */
public class ColumnConstraints extends ConstraintsBase {

    
Create a column constraint object with no properties set.

/**
     * Create a column constraint object with no properties set.
     */
    public ColumnConstraints() {
        super();
    }

    
Creates a column constraint object with a fixed width.
This is a convenience for setting the preferred width constraint to the
fixed value and the minWidth and maxWidth constraints to the USE_PREF_SIZE
flag to ensure the column is always that width.

Params:
  • width – the width of the column
/**
     * Creates a column constraint object with a fixed width.
     * This is a convenience for setting the preferred width constraint to the
     * fixed value and the minWidth and maxWidth constraints to the USE_PREF_SIZE
     * flag to ensure the column is always that width.
     *
     * @param width the width of the column
     */
    public ColumnConstraints(double width) {
        this();
        setMinWidth(USE_PREF_SIZE);
        setPrefWidth(width);
        setMaxWidth(USE_PREF_SIZE);
    }

    
Creates a column constraint object with a fixed size range.
This is a convenience for setting the minimum, preferred, and maximum
width constraints.

Params:
  • minWidth – the minimum width
  • prefWidth – the preferred width
  • maxWidth – the maximum width
/**
     * Creates a column constraint object with a fixed size range.
     * This is a convenience for setting the minimum, preferred, and maximum
     * width constraints.
     *
     * @param minWidth the minimum width
     * @param prefWidth the preferred width
     * @param maxWidth the maximum width
     */
    public ColumnConstraints(double minWidth, double prefWidth, double maxWidth) {
        this();
        setMinWidth(minWidth);
        setPrefWidth(prefWidth);
        setMaxWidth(maxWidth);
    }

    
Creates a column constraint object with a fixed size range, horizontal
grow priority, horizonal alignment, and horizontal fill behavior.

Params:
  • minWidth – the minimum width
  • prefWidth – the preferred width
  • maxWidth – the maximum width
  • hgrow – the horizontal grow priority
  • halignment – the horizonal alignment
  • fillWidth – the horizontal fill behavior
/**
     * Creates a column constraint object with a fixed size range, horizontal
     * grow priority, horizonal alignment, and horizontal fill behavior.
     *
     * @param minWidth the minimum width
     * @param prefWidth the preferred width
     * @param maxWidth the maximum width
     * @param hgrow the horizontal grow priority
     * @param halignment the horizonal alignment
     * @param fillWidth the horizontal fill behavior
     */
    public ColumnConstraints(double minWidth, double prefWidth, double maxWidth, Priority hgrow, HPos halignment, boolean fillWidth) {
        this(minWidth, prefWidth, maxWidth);
        setHgrow(hgrow);
        setHalignment(halignment);
        setFillWidth(fillWidth);
    }

    
The minimum width for the column.
This property is ignored if percentWidth is set.


The default value is USE_COMPUTED_SIZE, which means the minimum width
will be computed to be the largest minimum width of the column's content.

/**
     * The minimum width for the column.
     * This property is ignored if percentWidth is set.
     * <p>
     * The default value is USE_COMPUTED_SIZE, which means the minimum width
     * will be computed to be the largest minimum width of the column's content.
     */
    private DoubleProperty minWidth;

    public final void setMinWidth(double value) {
        minWidthProperty().set(value);
    }

    public final double getMinWidth() {
        return minWidth == null ? USE_COMPUTED_SIZE : minWidth.get();
    }

    public final DoubleProperty minWidthProperty() {
        if (minWidth == null) {
            minWidth = new DoublePropertyBase(USE_COMPUTED_SIZE) {

                @Override
                protected void invalidated() {
                    requestLayout();
                }

                @Override
                public Object getBean() {
                    return ColumnConstraints.this;
                }

                @Override
                public String getName() {
                    return "minWidth";
                }
            };
        }
        return minWidth;
    }

    
The preferred width for the column.
This property is ignored if percentWidth is set.


The default value is USE_COMPUTED_SIZE, which means the preferred width
will be computed to be the largest preferred width of the column's content.

/**
     * The preferred width for the column.
     * This property is ignored if percentWidth is set.
     * <p>
     * The default value is USE_COMPUTED_SIZE, which means the preferred width
     * will be computed to be the largest preferred width of the column's content.
     */
    private DoubleProperty prefWidth;

    public final void setPrefWidth(double value) {
        prefWidthProperty().set(value);
    }

    public final double getPrefWidth() {
        return prefWidth == null ? USE_COMPUTED_SIZE : prefWidth.get();
    }

    public final DoubleProperty prefWidthProperty() {
        if (prefWidth == null) {
            prefWidth = new DoublePropertyBase(USE_COMPUTED_SIZE) {

                @Override
                protected void invalidated() {
                    requestLayout();
                }

                @Override
                public Object getBean() {
                    return ColumnConstraints.this;
                }

                @Override
                public String getName() {
                    return "prefWidth";
                }
            };
        }
        return prefWidth;
    }

    
The maximum width for the column.
This property is ignored if percentWidth is set.


The default value is USE_COMPUTED_SIZE, which means the maximum width
will be computed to be the smallest maximum width of the column's content.

/**
     * The maximum width for the column.
     * This property is ignored if percentWidth is set.
     * <p>
     * The default value is USE_COMPUTED_SIZE, which means the maximum width
     * will be computed to be the smallest maximum width of the column's content.
     */
    private DoubleProperty maxWidth;

    public final void setMaxWidth(double value) {
        maxWidthProperty().set(value);
    }

    public final double getMaxWidth() {
        return maxWidth == null ? USE_COMPUTED_SIZE : maxWidth.get();
    }

    public final DoubleProperty maxWidthProperty() {
        if (maxWidth == null) {
            maxWidth = new DoublePropertyBase(USE_COMPUTED_SIZE) {

                @Override
                protected void invalidated() {
                    requestLayout();
                }

                @Override
                public Object getBean() {
                    return ColumnConstraints.this;
                }

                @Override
                public String getName() {
                    return "maxWidth";
                }
            };
        }
        return maxWidth;
    }

    
The width percentage of the column.  If set to a value greater than 0,
the column will be resized to this percentage of the gridpane's available
width and the other size constraints (minWidth, prefWidth, maxWidth, hgrow)
will be ignored.
The default value is -1, which means the percentage will be ignored.

/**
     * The width percentage of the column.  If set to a value greater than 0,
     * the column will be resized to this percentage of the gridpane's available
     * width and the other size constraints (minWidth, prefWidth, maxWidth, hgrow)
     * will be ignored.
     *
     * The default value is -1, which means the percentage will be ignored.
     */
    private DoubleProperty percentWidth;

    public final void setPercentWidth(double value) {
        percentWidthProperty().set(value);
    }

    public final double getPercentWidth() {
        return percentWidth == null ? -1 : percentWidth.get();
    }

    public final DoubleProperty percentWidthProperty() {
        if (percentWidth == null) {
            percentWidth = new DoublePropertyBase(-1) {

                @Override
                protected void invalidated() {
                    requestLayout();
                }

                @Override
                public Object getBean() {
                    return ColumnConstraints.this;
                }

                @Override
                public String getName() {
                    return "percentWidth";
                }
            };
        }
        return percentWidth;
    }


    
The horizontal grow priority for the column.  If set, the gridpane will
use this priority to determine whether the column should be given any
additional width if the gridpane is resized larger than its preferred width.
This property is ignored if percentWidth is set.


This default value is null, which means that the column's grow priority
will be derived from largest grow priority set on a content node.

/**
     * The horizontal grow priority for the column.  If set, the gridpane will
     * use this priority to determine whether the column should be given any
     * additional width if the gridpane is resized larger than its preferred width.
     * This property is ignored if percentWidth is set.
     * <p>
     * This default value is null, which means that the column's grow priority
     * will be derived from largest grow priority set on a content node.
     */
    private ObjectProperty<Priority> hgrow;

    public final void setHgrow(Priority value) {
        hgrowProperty().set(value);
    }

    public final Priority getHgrow() {
        return hgrow == null ? null : hgrow.get();
    }

    public final ObjectProperty<Priority> hgrowProperty() {
        if (hgrow == null) {
            hgrow = new ObjectPropertyBase<Priority>() {

                @Override
                protected void invalidated() {
                    requestLayout();
                }

                @Override
                public Object getBean() {
                    return ColumnConstraints.this;
                }

                @Override
                public String getName() {
                    return "hgrow";
                }
            };
        }
        return hgrow;
    }

    
The horizontal alignment for the column. If set, will be the default
horizontal alignment for nodes contained within the column.


The default value is null, which means the column alignment will fall
back to the default halignment set on the gridpane.

/**
     * The horizontal alignment for the column. If set, will be the default
     * horizontal alignment for nodes contained within the column.
     * <p>
     * The default value is null, which means the column alignment will fall
     * back to the default halignment set on the gridpane.
     */
    private ObjectProperty<HPos> halignment;

    public final void setHalignment(HPos value) {
        halignmentProperty().set(value);
    }

    public final HPos getHalignment() {
        return halignment == null ? null : halignment.get();
    }

    public final ObjectProperty<HPos> halignmentProperty() {
        if (halignment == null) {
            halignment = new ObjectPropertyBase<HPos>() {

                @Override
                protected void invalidated() {
                    requestLayout();
                }

                @Override
                public Object getBean() {
                    return ColumnConstraints.this;
                }

                @Override
                public String getName() {
                    return "halignment";
                }
            };
        }
        return halignment;
    }

    
The horizontal fill policy for the column.  The gridpane will
use this property to determine whether nodes contained within the column
should be expanded to fill the column or kept to their preferred widths.


The default value is true.

/**
     * The horizontal fill policy for the column.  The gridpane will
     * use this property to determine whether nodes contained within the column
     * should be expanded to fill the column or kept to their preferred widths.
     * <p>
     * The default value is true.
     *
     */
    private BooleanProperty fillWidth;

    public final void setFillWidth(boolean value) {
        fillWidthProperty().set(value);
    }

    public final boolean isFillWidth() {
        return fillWidth == null ? true : fillWidth.get();
    }

    public final BooleanProperty fillWidthProperty() {
        if (fillWidth == null) {
            fillWidth = new BooleanPropertyBase(true) {

                @Override
                protected void invalidated() {
                    requestLayout();
                }

                @Override
                public Object getBean() {
                    return ColumnConstraints.this;
                }

                @Override
                public String getName() {
                    return "fillWidth";
                }
            };
        }
        return fillWidth;
    }

    
Returns a string representation of this ColumnConstraints object. 
Returns:a string representation of this ColumnConstraints object.
/**
     * Returns a string representation of this {@code ColumnConstraints} object.
     * @return a string representation of this {@code ColumnConstraints} object.
     */
    @Override public String toString() {
        return "ColumnConstraints percentWidth="+getPercentWidth()+
                " minWidth="+getMinWidth()+
                " prefWidth="+getPrefWidth()+
                " maxWidth="+getMaxWidth()+
                " hgrow="+getHgrow()+
                " fillWidth="+isFillWidth()+
                " halignment="+getHalignment();
    }
}