com.vaadin.client.widgets

Class Grid.Column<C,T>

java.lang.Object

com.vaadin.client.widgets.Grid.Column<C,T>

Type Parameters:

C - the column type

T - the row type

Direct Known Subclasses:

ColumnConnector.CustomColumn, Grid.SelectionColumn

Enclosing class:

Grid<T>

public abstract static class Grid.Column<C,T>
extends Object

Base class for grid columns internally used by the Grid. The user should use Grid.Column when creating new columns.

Constructor Summary

Constructors

Constructor and Description
Column() Constructs a new column with a simple TextRenderer.
Column(Renderer<? super C> renderer) Constructs a new column with a custom renderer.
Column(String caption) Constructs a new column with a simple TextRenderer.
Column(String caption, Renderer<? super C> renderer) Constructs a new column with a custom renderer.

Method Summary

Modifier and Type	Method and Description
Grid.Column<C,T>	clearExpandRatio() Clears the column's expand ratio.
String	getAssistiveCaption() Returns the current header aria-label for this column.
int	getExpandRatio() Gets the expand ratio for this column.
String	getHeaderCaption() Returns the current header caption for this column.
String	getHidingToggleCaption() Gets the hiding toggle caption for this column.
double	getMaximumWidth() Gets the maximum width for this column.
double	getMinimumWidth() Gets the minimum width for this column.
Renderer<? super C>	getRenderer() The renderer to render the cell with.
abstract C	getValue(T row) Returns the data that should be rendered into the cell.
double	getWidth() Returns the pixel width of the column as given by the user.
double	getWidthActual() Returns the effective pixel width of the column.
boolean	isEditable() Returns whether the values in this column are editable by the user when the row editor is active.
boolean	isHandleWidgetEvents() Returns whether Grid should handle events from Widgets in this Column.
boolean	isHidable() Is it possible for the the user to hide this column.
boolean	isHidden() Returns whether this column is hidden.
boolean	isMinimumWidthFromContent() Gets whether the width of the contents in the column should be considered minimum width for this column.
boolean	isResizable() Returns whether this column can be resized by the user.
boolean	isSortable() Returns whether the user can sort the grid by this column.
Grid.Column<C,T>	setAssistiveCaption(String caption) Sets the header aria-label for this column.
protected void	setDefaultHeaderContent(Grid.HeaderCell cell) Resets the default header cell contents to column header captions.
Grid.Column<C,T>	setEditable(boolean editable) Sets whether the values in this column should be editable by the user when the row editor is active.
Grid.Column<C,T>	setExpandRatio(int ratio) Sets the ratio with which the column expands.
void	setHandleWidgetEvents(boolean handleWidgetEvents) Sets whether Grid should handle events from Widgets in this Column.
Grid.Column<C,T>	setHeaderCaption(String caption) Sets a header caption for this column.
Grid.Column<C,T>	setHidable(boolean hidable) Set whether it is possible for the user to hide this column or not.
Grid.Column<C,T>	setHidden(boolean hidden) Hides or shows the column.
Grid.Column<C,T>	setHidingToggleCaption(String hidingToggleCaption) Sets the hiding toggle's caption for this column.
Grid.Column<C,T>	setMaximumWidth(double pixels) Sets the maximum width for this column.
Grid.Column<C,T>	setMinimumWidth(double pixels) Sets the minimum width for this column.
void	setMinimumWidthFromContent(boolean minimumWidthFromContent) Sets whether the width of the contents in the column should be considered minimum width for this column.
Grid.Column<C,T>	setRenderer(Renderer<? super C> renderer) Sets a custom Renderer for this column.
Grid.Column<C,T>	setResizable(boolean resizable) Sets whether this column can be resized by the user.
Grid.Column<C,T>	setSortable(boolean sortable) Sets whether the column should be sortable by the user.
Grid.Column<C,T>	setWidth(double pixels) Sets the pixel width of the column.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Column

public Column()

Constructs a new column with a simple TextRenderer.

Column

public Column(String caption)
       throws IllegalArgumentException

Constructs a new column with a simple TextRenderer.

Parameters:

caption - The header caption for this column

Throws:

IllegalArgumentException - if given header caption is null

Column

public Column(Renderer<? super C> renderer)
       throws IllegalArgumentException

Constructs a new column with a custom renderer.

Parameters:

renderer - The renderer to use for rendering the cells

Throws:

IllegalArgumentException - if given Renderer is null

Column

public Column(String caption,
              Renderer<? super C> renderer)
       throws IllegalArgumentException

Constructs a new column with a custom renderer.

Parameters:

renderer - The renderer to use for rendering the cells

caption - The header caption for this column

Throws:

IllegalArgumentException - if given Renderer or header caption is null

Method Detail

setHeaderCaption

public Grid.Column<C,T> setHeaderCaption(String caption)

Sets a header caption for this column.

Parameters:

caption - The header caption for this column

Returns:

the column itself

getHeaderCaption

public String getHeaderCaption()

Returns the current header caption for this column.

Returns:

the header caption string

Since:

7.6

setAssistiveCaption

public Grid.Column<C,T> setAssistiveCaption(String caption)

Sets the header aria-label for this column.

Parameters:

caption - The header aria-label for this column

Returns:

the column itself

Since:

8.2

getAssistiveCaption

public String getAssistiveCaption()

Returns the current header aria-label for this column.

Returns:

the header aria-label string

Since:

8.2

getValue

public abstract C getValue(T row)

Returns the data that should be rendered into the cell. By default returning Strings and Widgets are supported. If the return type is a String then it will be treated as preformatted text.

To support other types you will need to pass a custom renderer to the column via the column constructor.

Parameters:

row - The row object that provides the cell content.

Returns:

The cell content

getRenderer

public Renderer<? super C> getRenderer()

The renderer to render the cell with. By default renders the data as a String or adds the widget into the cell if the column type is of widget type.

Returns:

The renderer to render the cell content with

setRenderer

public Grid.Column<C,T> setRenderer(Renderer<? super C> renderer)
                             throws IllegalArgumentException

Sets a custom Renderer for this column.

Parameters:

renderer - The renderer to use for rendering the cells

Returns:

the column itself

Throws:

IllegalArgumentException - if given Renderer is null

setWidth

public Grid.Column<C,T> setWidth(double pixels)

Sets the pixel width of the column. Use a negative value for the grid to autosize column based on content and available space.

This action is done "finally", once the current execution loop returns. This is done to reduce overhead of unintentionally always recalculate all columns, when modifying several columns at once.

If the column is currently hidden, then this set width has effect only once the column has been made visible again.

Parameters:

pixels - the width in pixels or negative for auto sizing

Returns:

this column

getWidth

public double getWidth()

Returns the pixel width of the column as given by the user.

Note: If a negative value was given to setWidth(double), that same negative value is returned here.

Note: Returns the value, even if the column is currently hidden.

Returns:

pixel width of the column, or a negative number if the column width has been automatically calculated.

See Also:

setWidth(double), getWidthActual()

getWidthActual

public double getWidthActual()

Returns the effective pixel width of the column.

This differs from getWidth() only when the column has been automatically resized, or when the column is currently hidden, when the value is 0.

Returns:

pixel width of the column.

setSortable

public Grid.Column<C,T> setSortable(boolean sortable)

Sets whether the column should be sortable by the user. The grid can be sorted by a sortable column by clicking or tapping the column's default header. Programmatic sorting using the Grid#sort methods is not affected by this setting.

Parameters:

sortable - true if the user should be able to sort the column, false otherwise

Returns:

the column itself

isSortable

public boolean isSortable()

Returns whether the user can sort the grid by this column.

Note: it is possible to sort by this column programmatically using the Grid#sort methods regardless of the returned value.

Returns:

true if the column is sortable by the user, false otherwise

setResizable

public Grid.Column<C,T> setResizable(boolean resizable)

Sets whether this column can be resized by the user.

Parameters:

resizable - true if this column should be resizable, false otherwise

Returns:

this column

Since:

7.6

isResizable

public boolean isResizable()

Returns whether this column can be resized by the user. Default is true.

Note: the column can be programmatically resized using setWidth(double) and #setWidthUndefined() regardless of the returned value.

Returns:

true if this column is resizable, false otherwise

Since:

7.6

setHidden

public Grid.Column<C,T> setHidden(boolean hidden)

Hides or shows the column. By default columns are visible before explicitly hiding them.

Parameters:

hidden - true to hide the column, false to show

Returns:

this column

Since:

7.5.0

isHidden

public boolean isHidden()

Returns whether this column is hidden. Default is false.

Returns:

true if the column is currently hidden, false otherwise

Since:

7.5.0

setHidable

public Grid.Column<C,T> setHidable(boolean hidable)

Set whether it is possible for the user to hide this column or not. Default is false.

Note: it is still possible to hide the column programmatically using setHidden(boolean).

Parameters:

hidable - true the user can hide this column, false otherwise

Returns:

this column

Since:

7.5.0

isHidable

public boolean isHidable()

Is it possible for the the user to hide this column. Default is false.

Note: the column can be programmatically hidden using setHidden(boolean) regardless of the returned value.

Returns:

true if the user can hide the column, false if not

Since:

7.5.0

setHidingToggleCaption

public Grid.Column<C,T> setHidingToggleCaption(String hidingToggleCaption)

Sets the hiding toggle's caption for this column. Shown in the toggle for this column in the grid's sidebar when the column is hidable.

The default value is null. In this case the header caption is used, see setHeaderCaption(String).

Parameters:

hidingToggleCaption - the caption for the hiding toggle for this column

Returns:

this column

Since:

7.5.0

getHidingToggleCaption

public String getHidingToggleCaption()

Gets the hiding toggle caption for this column.

Returns:

the hiding toggle's caption for this column

Since:

7.5.0

See Also:

setHidingToggleCaption(String)

toString

public String toString()

Overrides:

toString in class Object

setMinimumWidth

public Grid.Column<C,T> setMinimumWidth(double pixels)

Sets the minimum width for this column.

This defines the minimum guaranteed pixel width of the column when it is set to expand.

This action is done "finally", once the current execution loop returns. This is done to reduce overhead of unintentionally always recalculate all columns, when modifying several columns at once.

Parameters:

pixels - the minimum width

Returns:

this column

setMinimumWidthFromContent

public void setMinimumWidthFromContent(boolean minimumWidthFromContent)

Sets whether the width of the contents in the column should be considered minimum width for this column.

If this is set to true (default for backwards compatibility), then a column will not shrink to smaller than the width required to show the contents available when calculating the widths (first N rows).

If this is set to false, then a column will shrink if necessary to the minimum width defined by setMinimumWidth(double) when it is set to expand.

Parameters:

minimumWidthFromContent - true to reserve space for all contents, false to allow the column to shrink smaller than the contents

Since:

8.1

isMinimumWidthFromContent

public boolean isMinimumWidthFromContent()

Gets whether the width of the contents in the column should be considered minimum width for this column.

Returns:

true to reserve space for all contents, false to allow the column to shrink smaller than the contents

Since:

8.1

setMaximumWidth

public Grid.Column<C,T> setMaximumWidth(double pixels)

Sets the maximum width for this column.

This defines the maximum allowed pixel width of the column when it is set to expand.

This action is done "finally", once the current execution loop returns. This is done to reduce overhead of unintentionally always recalculate all columns, when modifying several columns at once.

Parameters:

pixels - the maximum width

Returns:

this column

setExpandRatio

public Grid.Column<C,T> setExpandRatio(int ratio)

Sets the ratio with which the column expands.

By default, all columns expand equally (treated as if all of them had an expand ratio of 1). Once at least one column gets a defined expand ratio, the implicit expand ratio is removed, and only the defined expand ratios are taken into account.

If a column has a defined width (setWidth(double)), it overrides this method's effects.

Example: A grid with three columns, with expand ratios 0, 1 and 2, respectively. The column with a ratio of 0 is exactly as wide as its contents requires. The column with a ratio of 1 is as wide as it needs, plus a third of any excess space, bceause we have 3 parts total, and this column reservs only one of those. The column with a ratio of 2, is as wide as it needs to be, plus two thirds of the excess width.

This action is done "finally", once the current execution loop returns. This is done to reduce overhead of unintentionally always recalculate all columns, when modifying several columns at once.

Parameters:

ratio - the expand ratio of this column. 0 to not have it expand at all. A negative number to clear the expand value.

Returns:

this column

clearExpandRatio

public Grid.Column<C,T> clearExpandRatio()

Clears the column's expand ratio.

Same as calling setExpandRatio(-1)

Returns:

this column

getMinimumWidth

public double getMinimumWidth()

Gets the minimum width for this column.

Returns:

the minimum width for this column

See Also:

setMinimumWidth(double)

getMaximumWidth

public double getMaximumWidth()

Gets the maximum width for this column.

Returns:

the maximum width for this column

See Also:

setMaximumWidth(double)

getExpandRatio

public int getExpandRatio()

Gets the expand ratio for this column.

Returns:

the expand ratio for this column

See Also:

setExpandRatio(int)

setEditable

public Grid.Column<C,T> setEditable(boolean editable)

Sets whether the values in this column should be editable by the user when the row editor is active. By default columns are editable.

Parameters:

editable - true to set this column editable, false otherwise

Returns:

this column

Throws:

IllegalStateException - if the editor is currently active

See Also:

Grid.editRow(int), Grid.isEditorActive()

isEditable

public boolean isEditable()

Returns whether the values in this column are editable by the user when the row editor is active.

Returns:

true if this column is editable, false otherwise

See Also:

setEditable(boolean)

setDefaultHeaderContent

protected void setDefaultHeaderContent(Grid.HeaderCell cell)

Resets the default header cell contents to column header captions.

Parameters:

cell - default header cell for this column

Since:

7.5.1

isHandleWidgetEvents

public boolean isHandleWidgetEvents()

Returns whether Grid should handle events from Widgets in this Column.

Returns:

true to handle events from widgets; false to not

Since:

8.3

setHandleWidgetEvents

public void setHandleWidgetEvents(boolean handleWidgetEvents)

Sets whether Grid should handle events from Widgets in this Column.

Parameters:

handleWidgetEvents - true to let grid handle events from widgets; false to not

Since:

8.3