Arrays in Flash

1
Arrays in Flash

• What is an Array
• Array is a list of cells, each cell in the list
  has a number to identify it (index or position).
• Each cell can be used to hold information such as
  text, or a number, or an image.
• Note An Array size or length are the same thing.
  It refers to the number of cells that store
  information in the Array.

2
Arrays in Flash

• To declare an array variable inside flash, use
  the following general form
• var array_nameArray new Array()
• Ex) var xArray new Array()
• This statement will generate an empty array.
• To insert a text element to this array
• X0 some text
• //Here the text value (some text) will be added
  to the first element //of the array.
• To insert a new numeric element (at position 1)
• X1 4235
• // here the value (4235) will be added to the
  second element of the //array.

3
Arrays in Flash

• Adding new elements to this array
• x2 ab
• X3 1000.6
• X4 asd
• You can notice that arrays created in flash can
  hold values with different data types.

x
0
1
2
3
4
positions
4235
some text
ab
1000.6
asd
elements
4
Arrays in Flash

• To get a value from the Array use
• myArrayNamex
• //Where x is index of the value from the Array
  you want to fetch.
• Ex) to print the value stored at index (2) of the
  array defined in the previous example
• trace(x2)
• Counting the Length of an Array
• To find the length of an array in flash use
• array_name.length

5
Arrays in Flash

• ex) the statement
• trace(x.length)
• will print (5) because array (x) has 5 elements.
• Exercise)
• Try (push()) function to add elements to an array
• Try (reverse()) function to order array elements
  in reverse order

6
Array Application

• Ex) This example shows how to control mouse
  cursor. The movements of mouse cursor will be
  captured and stored in an array. Then, these
  movements will be read and re-played again.
• Create a new flash file.
• Write stop() statement in the action panel of
  the first frame.
• Insert a button symbol onto the stage and write
  Start capturing as a caption.
• Add the following actionscript to the action
  panel of the button. Select the button then click
  F9 the write

7
Array Application

• on(release)
• gotoAndStop(5)
• Insert a key frame at frame 5.
• Write the following action script in the action
  panel of frame5
• var xaArraynew Array()
• var yaArray new Array()
• onEnterFrame function()
• xa.push(_xmouse)
• ya.push(_ymouse)

_xmouse return the x-coordinate of the current
location of the mouse cursor on stage
This process will continue repeatedly
Both valuse will be added to both arrays
_ymouse return the y-coordinate of the current
location of the mouse cursor on stage
8
Array Application

• Add a button onto the stage at frame5 with Stop
  capturing as a caption.
• In the action panel of that button, put the
  following actionsript
• on(release)
• delete onEnterFrame
• gotoAndStop(10)

This statement is used to stop the running
onEnterFrame function
Then, the movie transfers and stops at frame 10
9
Array Application

1. Insert a keyframe into frame10
2. Insert a movie clip symbol onto the stage at this
   frame and give it (m) as an instance name.
3. In the action panel of this frame, write the
   following actionscript code

10

• var iNumber0
• onEnterFramefunction()
• if(iltxa.length)
• m._x xai
• m._y yai
• ii1
• else
• delete onEnterFrame
• play()

This onEnterFrame repeats the process of reading
x and y- coordinate values from the arrays
(xa,ya) and giving them to the x and y
coordinates of the (m) symbol. This will result
in moving the (m) symbol