# Titanium.UI.iOS.ViewAttachmentBehavior

Dynamic behavior to support connections between two items.

Availability
3.2.0
9.2.0

# Overview

A view attachment behavior creates a dynamic connection between two items. To define a view attachment behavior:

  1. Use the Titanium.UI.iOS.createViewAttachmentBehavior method to create and define a behavior.
  2. Set the Titanium.UI.iOS.ViewAttachmentBehavior.anchorItem and Titanium.UI.iOS.ViewAttachmentBehavior.item properties.
  3. Add the behavior to the Titanium.UI.iOS.Animator.

To create a dynamic connection between an item and anchor point, use Titanium.UI.iOS.AnchorAttachmentBehavior.

# Examples

# Simple Example

The following example anchors a green block to either a red or blue block. Click on the red or blue block to change which one the green block is anchored to.

<img src="./viewattachment.gif" height= 275" style="border:1px solid black"/>

var win = Ti.UI.createWindow({backgroundColor: 'white', fullscreen: true});

// Create an Animator object using the window as the coordinate system
var animator = Ti.UI.iOS.createAnimator({referenceView: win});

var redBlock = Ti.UI.createView({
    backgroundColor: 'red',
    width: 25,
    height: 25,
    top: 10,
    left: 75
});
// Snap the red block so it does not move
var redSnap = Ti.UI.iOS.createSnapBehavior({
    snapPoint: {x: 75, y: 10},
    item: redBlock,
    damping: 0.0
});
animator.addBehavior(redSnap);

var greenBlock = Ti.UI.createView({
    backgroundColor: 'green',
    width: 25,
    height: 25,
    top: 50,
});

var WIDTH = Ti.Platform.displayCaps.platformWidth;
var blueBlock = Ti.UI.createView({
    backgroundColor: 'blue',
    width: 25,
    height: 25,
    top: 10,
    right: 75
});
// Snap the blue block so it does not move
var blueSnap = Ti.UI.iOS.createSnapBehavior({
    snapPoint: {x: WIDTH - 75, y: 10},
    item: blueBlock,
    damping: 0.0
});
animator.addBehavior(blueSnap);

// Anchor the green block to the red one when the app starts
var anchor = Ti.UI.iOS.createViewAttachmentBehavior({
    anchorItem: redBlock,
    item: greenBlock
});
animator.addBehavior(anchor);

// Simulate Earth's gravity to allow the green block to swing
var gravity = Ti.UI.iOS.createGravityBehavior({
    gravityDirection: {x: 0.0, y: 1.0}
});
gravity.addItem(greenBlock);
animator.addBehavior(gravity);

// Change the anchor item when clicking either the red or blue block
redBlock.addEventListener('click', function(e){
    anchor.anchorItem = redBlock;
});
blueBlock.addEventListener('click', function(e){
    anchor.anchorItem = blueBlock;
});

// Start the animation when the window opens
win.addEventListener('open', function(e){
    animator.startAnimator();
});

win.add(redBlock);
win.add(greenBlock);
win.add(blueBlock);
win.open();

# Properties

# anchorItem

Availability
3.2.0
9.2.0
anchorItem :Titanium.UI.View

Item to use as the anchor in this behavior.


# anchorOffset

Availability
3.2.0
9.2.0
anchorOffset :Point

Offset from the center point of the anchor item for the attachment.

Default: (0,0)


# apiName READONLY

Availability
3.2.0
9.2.0
apiName :String

The name of the API that this proxy corresponds to.

The value of this property is the fully qualified name of the API. For example, Titanium.UI.Button returns Ti.UI.Button.


# bubbleParent

Availability
3.2.0
9.2.0
bubbleParent :Boolean

Indicates if the proxy will bubble an event to its parent.

Some proxies (most commonly views) have a relationship to other proxies, often established by the add() method. For example, for a button added to a window, a click event on the button would bubble up to the window. Other common parents are table sections to their rows, table views to their sections, and scrollable views to their views. Set this property to false to disable the bubbling to the proxy's parent.

Default: true


# damping

Availability
3.2.0
9.2.0
damping :Number

Amount of damping to apply to the attachment behavior.

Default: 0


# distance

Availability
3.2.0
9.2.0
distance :Number

Distance, in points, between the two attachment points.

Default: 0


# frequency

Availability
3.2.0
9.2.0
frequency :Number

Frequency of oscillation for the behavior.

Default: 0


# item

Availability
3.2.0
9.2.0

Item to connect to use the attachment behavior.


# itemOffset

Availability
3.2.0
9.2.0
itemOffset :Point

Offset from the center point of the item for the attachment.

Default: (0,0)

# Methods

# addEventListener

Availability
3.2.0
9.2.0
addEventListener(name, callback) void

Adds the specified callback as an event listener for the named event.

Parameters

Name Type Description
name String

Name of the event.

callback Callback<Titanium.Event>

Callback function to invoke when the event is fired.

Returns

Type
void

# applyProperties

Availability
3.2.0
9.2.0
applyProperties(props) void

Applies the properties to the proxy.

Properties are supplied as a dictionary. Each key-value pair in the object is applied to the proxy such that myproxy[key] = value.

Parameters

Name Type Description
props Dictionary

A dictionary of properties to apply.

Returns

Type
void

# fireEvent

Availability
3.2.0
9.2.0
fireEvent(name[, event]) void

Fires a synthesized event to any registered listeners.

Parameters

Name Type Description
name String

Name of the event.

event Dictionary

A dictionary of keys and values to add to the Titanium.Event object sent to the listeners.

Returns

Type
void

# removeEventListener

Availability
3.2.0
9.2.0
removeEventListener(name, callback) void

Removes the specified callback as an event listener for the named event.

Multiple listeners can be registered for the same event, so the callback parameter is used to determine which listener to remove.

When adding a listener, you must save a reference to the callback function in order to remove the listener later:

var listener = function() { Ti.API.info("Event listener called."); }
window.addEventListener('click', listener);

To remove the listener, pass in a reference to the callback function:

window.removeEventListener('click', listener);

Parameters

Name Type Description
name String

Name of the event.

callback Callback<Titanium.Event>

Callback function to remove. Must be the same function passed to addEventListener.

Returns

Type
void