FlowLayout (Codename One API)

java.lang.Object
- com.codename1.ui.layouts.Layout
- - com.codename1.ui.layouts.FlowLayout

```
public class FlowLayout
extends Layout
```
FlowLayout is the default layout manager for Codename One Containers and Forms. It places components in a row one after another based on their preferred size. When it reaches the edge of the container it will break a line and start a new row.

Since flow layout isn't a constraint based layout it has a bunch of very useful enclose methods that can significantly reduce the code required to create the same UI e.g.:

This class works nicely for simple elements, however since Codename One doesn't reflow recursively (for performance) it can't accurately handle complex layouts. As a result when an element of varying size is placed in a flow layout this confuses the line breaking logic and fails in odd ways. That is why this layout should only be used for relatively simple use cases.

Flow layout supports aligning the component horizontally and vertically, it defaults to the top left alignment for LTR languages. E.g. the following alignments are supported thru the usage of setAlign & setValign.

E.g. you can align to the center

You can align to the right

You can align to the center and the middle horizontally

There are quite a few additional combinations that are possible with these API's.

See Also:

see the box layout X which is often a better choice than flow layout.

Constructor Summary

Constructors
Constructor and Description
`FlowLayout()` Creates a new instance of FlowLayout with left alignment
`FlowLayout(int orientation)` Creates a new instance of FlowLayout with the given orientation one of LEFT, RIGHT or CENTER
`FlowLayout(int orientation, int valign)` Creates a new instance of FlowLayout with the given orientation one of LEFT, RIGHT or CENTER and the vertical orientation
`FlowLayout(int orientation, int valign, boolean vAlignByRow)` Creates a new instance of FlowLayout with the given orientation one of LEFT, RIGHT or CENTER and the vertical orientation

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static Container`	`encloseBottom(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.BOTTOM), cmps);
`static Container`	`encloseBottomByRow(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.BOTTOM, true), cmps);
`static Container`	`encloseCenter(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.CENTER), cmps);
`static Container`	`encloseCenterBottom(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.CENTER, Component.BOTTOM), cmps);
`static Container`	`encloseCenterBottomByRow(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.CENTER, Component.BOTTOM, true), cmps);
`static Container`	`encloseCenterMiddle(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.CENTER, Component.CENTER), cmps);
`static Container`	`encloseCenterMiddleByRow(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.CENTER, Component.CENTER, true), cmps);
`static Container`	`encloseIn(Component... cmps)` Shorthand for `Container.encloseIn(com.codename1.ui.layouts.Layout, com.codename1.ui.Component...)` with a `FlowLayout instance` see:
`static Container`	`encloseLeftMiddle(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.CENTER), cmps);
`static Container`	`encloseLeftMiddleByRow(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.CENTER, true), cmps);
`static Container`	`encloseMiddle(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.CENTER), cmps);
`static Container`	`encloseMiddleByRow(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.CENTER, true), cmps);
`static Container`	`encloseRight(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.RIGHT), cmps);
`static Container`	`encloseRightBottom(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.RIGHT, Component.BOTTOM), cmps);
`static Container`	`encloseRightBottomByRow(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.RIGHT, Component.BOTTOM, true), cmps);
`static Container`	`encloseRightMiddle(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.RIGHT, Component.CENTER), cmps);
`static Container`	`encloseRightMiddleByRow(Component... cmps)` Shorthand for Container.encloseIn(new FlowLayout(Component.RIGHT, Component.CENTER, true), cmps);
`boolean`	`equals(Object o)` Indicates whether some other object is "equal to" this one.
`protected void`	`fillRow(Container target, int width, int start, int end)` This method tries to fill up the available space in a row.
`int`	`getAlign()` Alignment of the flow layout, defaults to LEFT
`Dimension`	`getPreferredSize(Container parent)` Returns the container preferred size
`int`	`getValign()` Indicates vertical alignment within the flow layout
`boolean`	`isFillRows()` Indicates whether the layout manager should try to fill up the available space in the row
`boolean`	`isValignByRow()` Returns whether vertical alignment is done internally or externally
`void`	`layoutContainer(Container parent)` Layout the given parent container children
`void`	`setAlign(int orientation)` Alignment of the flow layout, defaults to LEFT
`void`	`setFillRows(boolean fillRows)` Indicates whether the layout manager should try to fill up the available space in the row
`void`	`setValign(int valign)` Indicates vertical alignment within the flow layout
`void`	`setValignByRow(boolean internal)` When set to true vertical alignment will be performed by row (components within the container will be aligned vertically to each other in the same row) When set to false (which is default) vertical alignment relates to the alignment of this container in regards to external components
`String`	`toString()` Returns a string representation of the object.

Methods inherited from class com.codename1.ui.layouts.Layout
addLayoutComponent, cloneConstraint, getChildrenInTraversalOrder, getComponentConstraint, hashCode, isConstraintTracking, isOverlapSupported, obscuresPotential, overridesTabIndices, removeLayoutComponent, updateTabIndices

Methods inherited from class java.lang.Object
clone, getClass, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - FlowLayout
```
public FlowLayout()
```
    Creates a new instance of FlowLayout with left alignment
  - FlowLayout
```
public FlowLayout(int orientation)
```
    Creates a new instance of FlowLayout with the given orientation one of LEFT, RIGHT or CENTER
    
    Parameters:
    
    orientation - the orientation value
  - FlowLayout
```
public FlowLayout(int orientation,
                  int valign)
```
    Creates a new instance of FlowLayout with the given orientation one of LEFT, RIGHT or CENTER and the vertical orientation
    
    Parameters:
    
    orientation - the orientation value
    
    valign - the vertical orientation one of Component.TOP/BOTTOM/CENTER
  - FlowLayout
```
public FlowLayout(int orientation,
                  int valign,
                  boolean vAlignByRow)
```
    Creates a new instance of FlowLayout with the given orientation one of LEFT, RIGHT or CENTER and the vertical orientation
    
    Parameters:
    
    orientation - the orientation value
    
    valign - the vertical orientation one of Component.TOP/BOTTOM/CENTER
    
    vAlignByRow - whether vertical alignment should be computed by row elements
- Method Detail
  - layoutContainer
```
public void layoutContainer(Container parent)
```
    Layout the given parent container children
    
    Specified by:
    
    layoutContainer in class Layout
    
    Parameters:
    
    parent - the given parent container
  - fillRow
```
protected void fillRow(Container target,
                       int width,
                       int start,
                       int end)
```
    This method tries to fill up the available space in a row. This method is called if isFillRows() returns true.
    
    Parameters:
    
    target - the parent container
    
    width - the width of the row to fill
    
    start - the index of the first component in this row
    
    end - the index of the last component in this row
  - getPreferredSize
```
public Dimension getPreferredSize(Container parent)
```
    Returns the container preferred size
    
    Specified by:
    
    getPreferredSize in class Layout
    
    Parameters:
    
    parent - the parent container
    
    Returns:
    
    the container preferred size
  - toString
```
public String toString()
```
    Returns a string representation of the object. In general, the toString method returns a string that "textually represents" this object. The result should be a concise but informative representation that is easy for a person to read. It is recommended that all subclasses override this method. The toString method for class Object returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@', and the unsigned hexadecimal representation of the hash code of the object. In other words, this method returns a string equal to the value of: getClass().getName() + '@' + Integer.toHexString(hashCode())
    
    Overrides:
    
    toString in class Object
  - isFillRows
```
public boolean isFillRows()
```
    Indicates whether the layout manager should try to fill up the available space in the row
    
    Returns:
    
    the fillRows
  - setFillRows
```
public void setFillRows(boolean fillRows)
```
    Indicates whether the layout manager should try to fill up the available space in the row
    
    Parameters:
    
    fillRows - the fillRows to set
  - getValign
```
public int getValign()
```
    Indicates vertical alignment within the flow layout
    
    Returns:
    
    Component.TOP/BOTTOM/CENTER
  - setValign
```
public void setValign(int valign)
```
    Indicates vertical alignment within the flow layout
    
    Parameters:
    
    valign - one of Component.TOP/BOTTOM/CENTER
  - setValignByRow
```
public void setValignByRow(boolean internal)
```
    When set to true vertical alignment will be performed by row (components within the container will be aligned vertically to each other in the same row) When set to false (which is default) vertical alignment relates to the alignment of this container in regards to external components
    
    Parameters:
    
    internal - true for internal, false otherwise
  - isValignByRow
```
public boolean isValignByRow()
```
    Returns whether vertical alignment is done internally or externally
    
    Returns:
    
    whether vertical alignment is done internally or externally
  - getAlign
```
public int getAlign()
```
    Alignment of the flow layout, defaults to LEFT
    
    Returns:
    
    the orientation
  - setAlign
```
public void setAlign(int orientation)
```
    Alignment of the flow layout, defaults to LEFT
    
    Parameters:
    
    orientation - the orientation to set
  - equals
```
public boolean equals(Object o)
```
    Indicates whether some other object is "equal to" this one. The equals method implements an equivalence relation: It is reflexive: for any reference value x, x.equals(x) should return true. It is symmetric: for any reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true. It is transitive: for any reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true. It is consistent: for any reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the object is modified. For any non-null reference value x, x.equals(null) should return false. The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, for any reference values x and y, this method returns true if and only if x and y refer to the same object (x==y has the value true).
    
    Overrides:
    
    equals in class Layout
  - encloseIn
```
public static Container encloseIn(Component... cmps)
```
    Shorthand for Container.encloseIn(com.codename1.ui.layouts.Layout, com.codename1.ui.Component...) with a FlowLayout instance see:
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseCenter
```
public static Container encloseCenter(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.CENTER), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseRight
```
public static Container encloseRight(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.RIGHT), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseMiddle
```
public static Container encloseMiddle(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.CENTER), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseMiddleByRow
```
public static Container encloseMiddleByRow(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.CENTER, true), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseCenterMiddle
```
public static Container encloseCenterMiddle(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.CENTER, Component.CENTER), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseCenterMiddleByRow
```
public static Container encloseCenterMiddleByRow(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.CENTER, Component.CENTER, true), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseRightMiddle
```
public static Container encloseRightMiddle(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.RIGHT, Component.CENTER), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseRightMiddleByRow
```
public static Container encloseRightMiddleByRow(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.RIGHT, Component.CENTER, true), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseLeftMiddle
```
public static Container encloseLeftMiddle(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.CENTER), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseLeftMiddleByRow
```
public static Container encloseLeftMiddleByRow(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.CENTER, true), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseBottom
```
public static Container encloseBottom(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.BOTTOM), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseCenterBottom
```
public static Container encloseCenterBottom(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.CENTER, Component.BOTTOM), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseRightBottom
```
public static Container encloseRightBottom(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.RIGHT, Component.BOTTOM), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseBottomByRow
```
public static Container encloseBottomByRow(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.LEFT, Component.BOTTOM, true), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseCenterBottomByRow
```
public static Container encloseCenterBottomByRow(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.CENTER, Component.BOTTOM, true), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container
  - encloseRightBottomByRow
```
public static Container encloseRightBottomByRow(Component... cmps)
```
    Shorthand for Container.encloseIn(new FlowLayout(Component.RIGHT, Component.BOTTOM, true), cmps);
    
    Parameters:
    
    cmps - the components to enclose in a new container
    
    Returns:
    
    the new container

Class FlowLayout

Constructor Summary

Method Summary

Methods inherited from class com.codename1.ui.layouts.Layout

Methods inherited from class java.lang.Object

Constructor Detail

FlowLayout

FlowLayout

FlowLayout

FlowLayout

Method Detail

layoutContainer

fillRow

getPreferredSize

toString

isFillRows

setFillRows

getValign

setValign

setValignByRow

isValignByRow

getAlign

setAlign

equals

encloseIn

encloseCenter

encloseRight

encloseMiddle

encloseMiddleByRow

encloseCenterMiddle

encloseCenterMiddleByRow

encloseRightMiddle

encloseRightMiddleByRow

encloseLeftMiddle

encloseLeftMiddleByRow

encloseBottom

encloseCenterBottom

encloseRightBottom

encloseBottomByRow

encloseCenterBottomByRow

encloseRightBottomByRow