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Titanium SDK
Version12.6.2

You are reading 12.6.2. See this page in 13.4.1.

Titanium.UI.iOS.DynamicItemBehavior

proxyiPhoneiPadmacOSsince iPhone 3.2.0, iPad 3.2.0, macOS 9.2.0

Extends Titanium.Proxy

Base dynamic configuration for an item.

A dynamic item behavior configures the physics attributes for one or more items. These attributes, such as density and resistance, affects the behavior of the object when other behaviors, such as push forces or collisions, are applied to it. To define a dynamic behavior for an item:

  1. Use the Titanium.UI.iOS.createDynamicItemBehavior method to create and define the behavior.
  2. Use the addItem method to add items to the behavior.
  3. Add the behavior to an Animator object.

Examples

Simple Example

The following example create two blocks, which are pushed towards each other. Because the red block is more dense and has higher resistance than the blue block, the red block moves steadily to the left, while the blue block spins around unpredictably.

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});

// Create a red block
var redBlock = Ti.UI.createView({
    backgroundColor: 'red',
    width: 25,
    height: 25,
    top: 25,
    left: 25
});

// Change the physics attributes of the red block
var redDynamic = Ti.UI.iOS.createDynamicItemBehavior({
    density: 20.0,
    angularResistance: 1.0,
    friction: 1.0,
    resistance: 1.0,
    allowsRotation: false
});
redDynamic.addItem(redBlock);

// Apply a left push to the red block
var redPush = Ti.UI.iOS.createPushBehavior({
    pushDirection: {x: 2.0, y: 0.0}
});
redPush.addItem(redBlock);

// Create a blue block
var blueBlock = Ti.UI.createView({
    backgroundColor: 'blue',
    width: 50,
    height: 50,
    top: 25,
    right: 25
});

// Change the physics attributes of the blue block
var blueDynamic = Ti.UI.iOS.createDynamicItemBehavior({
    elasticity: 1.0,
});
blueDynamic.addItem(blueBlock);

// Apply a right push to the blue block
var bluePush = Ti.UI.iOS.createPushBehavior({
    pushDirection: {x: -2.0, y: 0.0}
});
bluePush.addItem(blueBlock);

// Create the collision behavior so the items can collide
var collision = Ti.UI.iOS.createCollisionBehavior();
collision.addItem(redBlock);
collision.addItem(blueBlock);

animator.addBehavior(redDynamic);
animator.addBehavior(redPush);
animator.addBehavior(blueDynamic);
animator.addBehavior(bluePush);
animator.addBehavior(collision);

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

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

Properties 9

Specifies if this item can rotate.

Set to true to enable this behavior or false to disable.

Default: true

Specifies the angular resistance of this item.

The greater the value, the greater the angular damping and rotation slows to a stop faster.

Default: 0

apiName

Stringsince Android 3.2.0, iPhone 3.2.0, iPad 3.2.0, macOS 9.2.0read-only

Inherited from Titanium.Proxy

The name of the API that this proxy corresponds to.

bubbleParent

Booleansince Android 3.0.0, iPhone 3.0.0, iPad 3.0.0, macOS 9.2.0

Inherited from Titanium.Proxy

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

Default: true

density

Number

Specifies the relative mass density of this item.

An item's density along with its size determines its effective mass and affects its dynamic behavior.

Default: 1

Specifies the elasticity applied to collisions for this item.

A value of 0.0 indicates no bounce upon collision, while 1.0 indicates a completely elastic collision.

Default: 0

friction

Number

Specifies the linear resistance of the item when it slides against another item.

A value of 0.0 indicates no friction, while 1.0 indicates strong friction. Use higher numbers to apply even higher friction.

Default: 0

Specifies the linear resistance of this item which reduces linear velocity over time.

A value of 0.0 indicates no velocity damping.

Default: 0

Methods 10

Adds a specified angular velocity for the item.

Parameters
ParametersTypeDescription
itemTitanium.UI.View

Item to add the velocity for.

velocityNumber

Velocity to add or subtract in radians per second. If the current velocity is positive, the item spins clockwise. A negative value means the item spins counter-clockwise.

Inherited from Titanium.Proxy

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

Parameters
ParametersTypeDescription
nameString

Name of the event.

callbackCallback<Titanium.Event>

Callback function to invoke when the event is fired.

4 fields
bubbles Boolean

True if the event will try to bubble up if possible.

cancelBubble Boolean

Set to true to stop the event from bubbling.

source Object

Source object that fired the event.

type String

Name of the event fired.

Adds an item to this behavior.

Parameters
ParametersTypeDescription
itemTitanium.UI.View

View object to add to the behavior.

Adds a specified linear velocity for the item.

Parameters
ParametersTypeDescription
itemTitanium.UI.View

Item to add the velocity for.

velocityPoint

Velocity to add or substract in points per second in the x and y directions.

Inherited from Titanium.Proxy

Fires a synthesized event to any registered listeners.

Parameters
ParametersTypeDescription
nameString

Name of the event.

event?Dictionary

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

Inherited from Titanium.Proxy

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

Parameters
ParametersTypeDescription
nameString

Name of the event.

callbackCallback<Titanium.Event>

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

4 fields
bubbles Boolean

True if the event will try to bubble up if possible.

cancelBubble Boolean

Set to true to stop the event from bubbling.

source Object

Source object that fired the event.

type String

Name of the event fired.