Titanium.Codec

A module for translating between primitive types and raw byte streams.

The Codec module can be used for encoding strings and numbers into Buffer objects, and decoding primitive types from buffers.

Byte Order

Multi-byte data can be stored in two different byte orders: big-endian or little-endian. In big-endian byte order, the most significant or highest-value byte is stored first. For example, the 4-byte integer 0xFEDCBA98 is made up of the bytes 0xFE, 0xDC, 0xBA and 0x98, from most-significant to least-significant.

If we represent a buffer as an array of byte values, a big-endian encoding of 0xFEDCBA98 would look like this:

[ 0xFE, 0xDC, 0xBA, 0x98 ]

In little-endian order, the bytes would be stored in this order:

[ 0x98, 0xBA, 0xDC, 0xFE ]

For 8-bit character encodings, including ASCII, Latin-1 and UTF-8, byte order is not significant: the text is a sequence of individual bytes.

For UTF-16, text is represented as a sequence of 16-bit values. For example, a capital T in UTF-16 is 0x0054, and lowercase i is 0x0069. If we encode the string "Ti" with UTF-16 in big-endian byte order, we get:

[ 0x00, 0x54, 0x00, 0x69 ]

In UTF-16 with little-endian byte order, "Ti" is encoded as:

[ 0x54, 0x00, 0x69, 0x00 ]

Note that the bytes for each character are stored least-significant byte first, but the order of the characters is unchanged.

Extends: Titanium.Module · Since: 1.7 · Platforms: android, iphone, ipad, macos

Properties

apiName

extended

3.2.0

3.2.0

3.2.0

9.2.0

Type: 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, Button
returns Ti.UI.Button.

BIG_ENDIAN

0.9

0.9

0.9

9.2.0

Type: Number

Big endian (network) byte order -- that is, the most significant byte first.

See "Byte Order" in the main discussion of Titanium.Codec for more information.

bubbleParent

extended

3.0.0

3.0.0

3.0.0

9.2.0

Type: 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.

CHARSET_ASCII

0.9

0.9

0.9

9.2.0

Type: String

ASCII character encoding..

See also: ASCII on Wikipedia.

CHARSET_ISO_LATIN_1

0.9

0.9

0.9

9.2.0

Type: String

ISO 8859-1 (Latin-1) character encoding.

See also: ISO/IEC 8859-1 on Wikipedia.

CHARSET_UTF16

0.9

0.9

0.9

9.2.0

Type: String

UTF-16 character encoding with default byte order.

See also: UTF-16/UCS2 on Wikipedia.

CHARSET_UTF16BE

0.9

0.9

0.9

9.2.0

Type: String

UTF-16 character encoding with big endian byte order.

See also: UTF-16/UCS2 on Wikipedia.

CHARSET_UTF16LE

0.9

0.9

0.9

9.2.0

Type: String

UTF-16 character encoding with little endian byte order.

See also: UTF-16/UCS2 on Wikipedia.

CHARSET_UTF8

0.9

0.9

0.9

9.2.0

Type: String

UTF-8 character encoding.

See also: UTF-8 on Wikipedia.

lifecycleContainer

extended

3.6.0

Type: Titanium.UI.Window, Titanium.UI.TabGroup

The Window or TabGroup whose Activity lifecycle should be triggered on the proxy.

If this property is set to a Window or TabGroup, then the corresponding Activity lifecycle event callbacks
will also be called on the proxy. Proxies that require the activity lifecycle will need this property set
to the appropriate containing Window or TabGroup.

LITTLE_ENDIAN

0.9

0.9

0.9

9.2.0

Type: Number

Little endian byte order -- that is, the least significant byte first.

See "Byte Order" in the main discussion of Titanium.Codec for more information.

TYPE_BYTE

0.9

0.9

0.9

9.2.0

Type: String

8-bit integer encoding type.

TYPE_DOUBLE

0.9

0.9

0.9

9.2.0

Type: String

64-bit double precision floating-point type.

TYPE_FLOAT

0.9

0.9

0.9

9.2.0

Type: String

32-bit single precision floating-point type.

TYPE_INT

0.9

0.9

0.9

9.2.0

Type: String

32-bit integer encoding type.

TYPE_LONG

0.9

0.9

0.9

9.2.0

Type: String

64-bit integer encoding type.

TYPE_SHORT

0.9

0.9

0.9

9.2.0

Type: String

16-bit integer encoding type.

Methods

addEventListener

extended

0.9

0.9

0.9

9.2.0

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

Parameters:

Name	Type	Summary	Optional
name	String	Name of the event.	No
callback	Callback<Titanium.Event>	Callback function to invoke when the event is fired.	No

applyProperties

extended

3.0.0

3.0.0

3.0.0

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	Summary	Optional
props	Dictionary	A dictionary of properties to apply.	No

decodeNumber

0.9

0.9

0.9

9.2.0

Decodes a number from the source buffer using the specified data type.

Takes a set of named parameters in the options argument.

Bytes are read from the source buffer and decoded as the specified data type, type.

Two optional parameters can also be specified in options:

• If position is included in the options dictionary, reads data from the
  buffer starting at position.

• If byteOrder is included in the options dictionary, the specified byte order
  is used -- otherwise, the native byte order is assumed.

Throws an exception if source is null, or position is greater than source.length

Parameters:

Name	Type	Summary	Optional
options	DecodeNumberDict	Named parameters.	No

Returns: Number — Number decoded from `source`.

decodeString

0.9

0.9

0.9

9.2.0

Decodes the source buffer into a String using the supplied character set.

Takes a set of named parameters in the options argument.

Bytes are read from the source buffer and decoded as a string.

Several optional parameters can also be specified in options:

• If position is specified, bytes are read from source starting at position.

• If length is specified, no more than length bytes are read.

• If charset is specified, it determines the character encoding used to decode the
  string. Otherwise, UTF-8 is assumed.

Throws an exception if charset is not a valid character set, source is null,
or either position, length, or position+length is greater than source.length.

Parameters:

Name	Type	Summary	Optional
options	DecodeStringDict	Named parameters.	No

Returns: String — The decoded string

encodeNumber

0.9

0.9

0.9

9.2.0

Encodes a number and writes it to a buffer.

Takes a set of named parameters passed in the options argument.

Encodes the number source into dest using the passed in data type.

Two optional parameters can also be specified in options:

• If position is included in the options dictionary, writes the encoded number
  to the buffer starting at position.

• If byteOrder is included in the options dictionary, the specified byte order
  is used -- otherwise, the native byte order is assumed.

Parameters:

Name	Type	Summary	Optional
options	EncodeNumberDict	Named parameters.	No

Returns: Number — Position _after_ the encoded number in `dest`.

encodeString

0.9

0.9

0.9

9.2.0

Encodes a string into a series of bytes in a buffer using the specified character set.

Takes a set of named parameters in the options argument.

The string is read from source and written to the buffer dest.

Several optional parameters can also be specified in options:

• If charset is included, the string is encoded using the specified character
  encoding.

• If destPosition is included, data is written into the buffer starting at
  the specified position.

• If sourcePosition is included, a substring of the source string starting at the
  specified position is encoded.

• If sourceLength is included, at most the specified number of characters
  are encoded.

Throws an exception if charset is not a valid character set,
source is null, or either sourcePosition, sourceLength, or
sourcePosition+sourceLength is greater than source.length.

Parameters:

Name	Type	Summary	Optional
options	Dictionary<EncodeStringDict>	Named parameters.	No

Returns: Number — An index indicating the first byte in the destination buffer _after_ the encoded string.

fireEvent

extended

0.9

0.9

0.9

9.2.0

Fires a synthesized event to any registered listeners.

Parameters:

Name	Type	Summary	Optional
name	String	Name of the event.	No
event	Dictionary	A dictionary of keys and values to add to the Titanium.Event object sent to the listeners.	Yes

getNativeByteOrder

0.9

0.9

0.9

9.2.0

Get the OS native byte order (either Titanium.Codec.BIG_ENDIAN or
Titanium.Codec.LITTLE_ENDIAN).

See "Byte Order" in the main discussion of Titanium.Codec for more information.

Returns: Number — OS native byte order.

removeEventListener

extended

0.9

0.9

0.9

9.2.0

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	Summary	Optional
name	String	Name of the event.	No
callback	Callback<Titanium.Event>	Callback function to remove. Must be the same function passed to addEventListener.	No