Tài liệu Flash: ActionScript Language Reference- P10 ppt

904 Chapter 2: ActionScript Language ReferenceExample The following example creates a text field called my_txt, and uses two buttons called scrollUp_btn and scrollDown_btn to scroll the

onChanged event because the code recognizes changes that are made to the text field.

902 Chapter 2: ActionScript Language Reference

Event handler/listener; invoked when one of the text field scroll properties changes

A reference to the text field instance is passed as a parameter to the onScroller handler You can capture this data by putting a parameter in the event handler method For example, the following code uses my_txt as the parameter that is passed to the onScroller event handler The parameter

is then used in a trace() statement to send the instance name of the text field to the Output panel

myTextField.onScroller = function (my_txt:TextField) {

trace (my_txt._name + " scrolled");

};

The TextField.onScroller event handler is commonly used to implement scroll bars Scroll

bars typically have a thumb or other indicator that shows the current horizontal or vertical

scrolling position in a text field Text fields can be navigated using the mouse and keyboard, which causes the scroll position to change The scroll bar code needs to be notified if the scroll position changes because of such user interaction, which is what TextField.onScroller is used for

onScroller is called whether the scroll position changed because of a users interaction with the text field, or programmatic changes The onChanged handler fires only if a user interaction causes the change These two options are necessary because often one piece of code changes the scrolling position, while the scroll bar code is unrelated and won't know that the scroll position changed without being notified

904 Chapter 2: ActionScript Language Reference

Example

The following example creates a text field called my_txt, and uses two buttons called

scrollUp_btn and scrollDown_btn to scroll the contents of the text field When the

onScroller event handler is called, a trace statement is used to display information in the Output panel Create two buttons with instance names scrollUp_btn and scrollDown_btn,

and add the following ActionScript to your FLA or AS file:

this.createTextField("scroll_txt", this.getNextHighestDepth(), 10, 10, 160, 20);

this.createTextField("my_txt", this.getNextHighestDepth(), 10, 30, 320, 240); my_txt.multiline = true;

my_txt.wordWrap = true;

for (var i = 0; i<10; i++) {

my_txt.text += "Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet dolore magna aliquam erat volutpat.";

If there is no previously focused object, oldFocus contains a null value.

Example

See the example for TextField.onKillFocus

See Also

TextField.onKillFocus

906 Chapter 2: ActionScript Language Reference

this.createTextField("first_txt", this.getNextHighestDepth(), 10, 10, 160, 22);

The following information is displayed in the Output panel:

first_txt's _parent is: _level0

second_txt's _parent is: _level0.holder_mc

See also

Button._parent , MovieClip._parent , _root , targetPath()

password text field When password mode is enabled, the Cut and Copy commands and their

corresponding keyboard accelerators will not function This security mechanism prevents an unscrupulous user from using the shortcuts to discover a password on an unattended computer

Example

The following example creates two text fields: username_txt and password_txt Text is entered into both text fields; however, password_txt has the password property set to true Therefore, the characters display as asterisks instead of as characters in the password_txt field

this.createTextField("username_txt", this.getNextHighestDepth(), 10, 10, 100, 22);

908 Chapter 2: ActionScript Language Reference

Note: Although you can specify this property for a TextField object, it is actually a global property,

and you can specify its value simply as _quality For more information, see the _quality property.

The _quality property can be set to the following values:

• "LOW" Low rendering quality Graphics are not anti-aliased, and bitmaps are not smoothed

• "MEDIUM" Medium rendering quality Graphics are anti-aliased using a 2 x 2 pixel grid, but bitmaps are not smoothed Suitable for movies that do not contain text

• "HIGH" High rendering quality Graphics are anti-aliased using a 4 x 4 pixel grid, and bitmaps are smoothed if the movie is static This is the default rendering quality setting used by Flash

• "BEST" Very high rendering quality Graphics are anti-aliased using a 4 x 4 pixel grid and bitmaps are always smoothed

Example

The following example sets the rendering quality to LOW:

my_txt._quality = "LOW";

this.createTextField("my_txt", this.getNextHighestDepth(), 10, 10, 160, 20); my_txt.border = true;

910 Chapter 2: ActionScript Language Reference

Example

The following example creates a text field that you can remove from the Stage when you click the remove_btn instance Create a button and call it remove_btn, and then add the following ActionScript to your FLA or AS file

this.createTextField("my_txt", this.getNextHighestDepth(), 10, 10, 300, 22); my_txt.text = new Date().toString();

my_txt.border = true;

remove_btn.onRelease = function() {

my_txt.removeTextField();

};

You can use the replaceSel() method to insert and delete text without disrupting the character and paragraph formatting of the rest of the text.

You must use Selection.setFocus() to focus the field before issuing this command

Example

The following example code creates a multiline text field with text on the Stage When you select some text and then right-click or Control-click over the text field, you can select Enter current date from the context menu This selection calls a function that replaces the selected text with the current date

this.createTextField("my_txt", this.getNextHighestDepth(), 10, 10, 320, 240); my_txt.border = true;

right-var my_cm:ContextMenu = new ContextMenu();

my_cm.customItems.push(new ContextMenuItem("Enter current date", enterDate)); function enterDate(obj:Object, menuItem:ContextMenuItem) {

var today_str:String = new Date().toString();

var date_str:String = today_str.split(" ", 3).join(" ");

912 Chapter 2: ActionScript Language Reference

Property; indicates the set of characters that a user may enter into the text field If the value of the

restrict property is null, you can enter any character If the value of the restrict property is

an empty string, you can’t enter any character If the value of the restrict property is a string of characters, you can enter only characters in the string into the text field The string is scanned from left to right A range may be specified using the dash (-) This only restricts user interaction;

a script may put any text into the text field This property does not synchronize with the Embed Font Outlines check boxes in the Property inspector

If the string begins with ^, all characters are initially accepted and succeeding characters in the string are excluded from the set of accepted characters If the string does not begin with ^, no characters are initially accepted and succeeding characters in the string are included in the set of accepted characters

You can use a backslash to enter a ^ or - verbatim The accepted backslash sequences are \-, \^ or

\\ The backslash must be an actual character in the string, so when specified in ActionScript, a double backslash must be used For example, the following code includes only the dash (-) and caret (^):

my_txt.restrict = "\\-\\^";

The ^ may be used anywhere in the string to toggle between including characters and excluding characters The following code includes only uppercase letters, but excludes the uppercase letter Q:

my_txt.restrict = "A-Z^Q";

You can use the \u escape sequence to construct restrict strings The following code includes only the characters from ASCII 32 (space) to ASCII 126 (tilde)

my_txt.restrict = "\u0020-\u007E";

914 Chapter 2: ActionScript Language Reference

Property; the rotation of the text field, in degrees, from its original orientation Values from

0 to 180 represent clockwise rotation; values from 0 to -180 represent counterclockwise rotation Values outside this range are added to or subtracted from 360 to obtain a value within the range For example, the statement my_txt._rotation = 450 is the same as my_txt._rotation = 90.Rotation values are not supported for text files that use device fonts You must use embedded fonts to use _rotation with a text field

Example

In this example, you need to create a dynamic text field called my_txt, and then use the following ActionScript to embed fonts and rotate the text field The reference to my font refers to a Font symbol in the library, with linkage set to my font

var my_fmt:TextFormat = new TextFormat();

my_fmt.font = "my font";

this.createTextField("my_txt", this.getNextHighestDepth(), 10, 10, 160, 120); my_txt.wordWrap = true;

The units of horizontal scrolling are pixels, while the units of vertical scrolling are lines

Horizontal scrolling is measured in pixels because most fonts you typically use are proportionally spaced; meaning, the characters can have different widths Flash performs vertical scrolling by line because users usually want to see a line of text in its entirety, as opposed to seeing a partial line Even if there are multiple fonts on a line, the height of the line adjusts to fit the largest font in use

For more information on scrolling text, see “Creating scrolling text” in Using Flash.

Example

The following example sets the maximum value for the scrolling text field my_txt Create two buttons, scrollUp_btn and scrollDown_btn, to scroll the text field Add the following ActionScript to your FLA or AS file

this.createTextField("scroll_txt", this.getNextHighestDepth(), 10, 10, 160, 20);

this.createTextField("my_txt", this.getNextHighestDepth(), 10, 30, 320, 240); my_txt.multiline = true;

my_txt.wordWrap = true;

for (var i = 0; i<10; i++) {

my_txt.text += "Lorem ipsum dolor sit amet, consectetuer adipiscing elit, sed diam nonummy nibh euismod tincidunt ut laoreet dolore magna aliquam erat volutpat.";

916 Chapter 2: ActionScript Language Reference

Property; a Boolean value that indicates whether the text field is selectable The value true

indicates that the text is selectable The selectable property controls whether a text field is selectable, and not whether a text field is editable A dynamic text field can be selectable even if it's not editable If a dynamic text field is not selectable, that means you cannot select its text

If selectable is set to false, the text in the text field does not respond to selection commands from the mouse or keyboard, and the text cannot be copied using the Copy command If selectable is set to true, the text in the text field can be selected using the mouse or keyboard You can select text this way even if the text field is a dynamic text field instead of an input text field The text can be copied using the Copy command

Example

The following example creates a selectable text field that constantly updates with the current date and time

this.createTextField("date_txt", this.getNextHighestDepth(), 10, 10, 100, 22); date_txt.autoSize = true;

918 Chapter 2: ActionScript Language Reference

TextField.setTextFormat()

Availability

Flash Player 6

Usage

my_txt.setTextFormat (textFormat:TextFormat) : Void

my_txt.setTextFormat (index:Number, textFormat:TextFormat) : Void

my_txt.setTextFormat (beginIndex:Number, endIndex:Number,

textFormat that is set to null will not be applied By default, all of the properties of a newly created TextFormat object are set to null

There are two types of formatting information in a TextFormat object: character level, and paragraph level formatting Each character in a text field might have its own character formatting settings, such as font name, font size, bold, and italic

For paragraphs, the first character of the paragraph is examined for the paragraph formatting settings for the entire paragraph Examples of paragraph formatting settings are left margin, right margin, and indentation

The setTextFormat() method changes the text formatting applied to an individual character, to

a range of characters, or to the entire body of text in a text field

Usage 1: Applies the properties of textFormat to all text in the text field

Usage 2: Applies the properties of textFormat to the character at position index

Usage 3: Applies the properties of the textFormat parameter to the span of text from the beginIndex parameter to the endIndex parameter

TextField.setTextFormat() 919

Notice that any text inserted manually by the user, or replaced by means of TextField.replaceSel(), receives the text field's default formatting for new text, and not the formatting specified for the text insertion point To set a text field’s default formatting for new text, use

var string1:String = "Sample string number one."+newline;

var string2:String = "Sample string number two."+newline;

this.createTextField("my_txt", this.getNextHighestDepth(), 0, 0, 300, 200); my_txt.multiline = true;

my_txt.wordWrap = true;

my_txt.text = string1;

var firstIndex:Number = my_txt.length;

my_txt.text += string2;

var secondIndex:Number = my_txt.length;

my_txt.setTextFormat(0, firstIndex, format1_fmt);

my_txt.setTextFormat(firstIndex, secondIndex, format2_fmt);

See also

TextField.setNewTextFormat(), TextFormat class

920 Chapter 2: ActionScript Language Reference

The style sheet associated with a text field may be changed at any time If the style sheet in use is changed, the text field is redrawn using the new style sheet The style sheet may be set to null or

undefined to remove the style sheet If the style sheet in use is removed, the text field is redrawn without a style sheet The formatting done by a style sheet is not retained if the style sheet is removed

news_txt.multiline = true;

news_txt.html = true;

var newsText:String = "<p class='headline'>Description</p> Method; starts loading the CSS file into styleSheet The load operation is asynchronous; use the <span class='bold'>TextField.StyleSheet.onLoad</span> callback handler to determine when the file has finished loading <span

class='important'>The CSS file must reside in exactly the same domain as the SWF file that is loading it.</span> For more information about restrictions

on loading data across domains, see Flash Player security features."; news_txt.htmlText = newsText;

922 Chapter 2: ActionScript Language Reference

Example

The following example creates several text fields, called one_txt, two_txt, three_txt and

four_txt The three_txt text field has the tabEnabled property set to false, so it is excluded from the automatic tab ordering

this.createTextField("one_txt", this.getNextHighestDepth(), 10, 10, 100, 22); one_txt.border = true;

one_txt.type = "input";

this.createTextField("two_txt", this.getNextHighestDepth(), 10, 40, 100, 22); two_txt.border = true;

two_txt.type = "input";

this.createTextField("three_txt", this.getNextHighestDepth(), 10, 70, 100, 22);

three_txt.border = true;

three_txt.type = "input";

this.createTextField("four_txt", this.getNextHighestDepth(), 10, 100, 100, 22);

Property; lets you customize the tab ordering of objects in a SWF file You can set the tabIndex

property on a button, movie clip, or text field instance; it is undefined by default

If any currently displayed object in the SWF file contains a tabIndex property, automatic tab ordering is disabled, and the tab ordering is calculated from the tabIndex properties of objects in the SWF file The custom tab ordering only includes objects that have tabIndex properties.The tabIndex property must be a positive integer The objects are ordered according to their

tabIndex properties, in ascending order An object with a tabIndex value of 1 precedes an object with a tabIndex value of 2 If two objects have the same tabIndex value, the one that precedes the other in the tab ordering is undefined

The custom tab ordering defined by the tabIndex property is flat This means that no attention

is paid to the hierarchical relationships of objects in the SWF file All objects in the SWF file with

tabIndex properties are placed in the tab order, and the tab order is determined by the order of the tabIndex values If two objects have the same tabIndex value, the one that goes first is

undefined You shouldn’t use the same tabIndex value for multiple objects

Example

The following ActionScript dynamically creates four text fields and assigns them to a custom tab order Add the following ActionScript to your FLA or AS file:

this.createTextField("one_txt", this.getNextHighestDepth(), 10, 10, 100, 22); one_txt.border = true;

one_txt.type = "input";

this.createTextField("two_txt", this.getNextHighestDepth(), 10, 40, 100, 22); two_txt.border = true;

two_txt.type = "input";

this.createTextField("three_txt", this.getNextHighestDepth(), 10, 70, 100, 22);

three_txt.border = true;

three_txt.type = "input";

this.createTextField("four_txt", this.getNextHighestDepth(), 10, 100, 100, 22);

four_txt.border = true;

four_txt.type = "input";

924 Chapter 2: ActionScript Language Reference

Read-only property; the target path of the text field instance specified by my_txt. The _self

target specifies the current frame in the current window, _blank specifies a new window, _parent

specifies the parent of the current frame, and _top specifies the top-level frame in the current window

Example

The following ActionScript creates a text field called my_txt and outputs the target path of the new field, in both slash and dot notation

this.createTextField("my_txt", this.getNextHighestDepth(), 10, 10, 100, 22); trace(my_txt._target); // output: /my_txt

trace(eval(my_txt._target)); // output: _level0.my_txt

926 Chapter 2: ActionScript Language Reference

Example

The following example creates an HTML text field called my_txt, and assigns an formatted string of text to the field When you trace the htmlText property, the Output panel displays the HTML-formatted string When you trace the value of the text property, the unformatted string with HTML tags displays in the Output panel

HTML-this.createTextField("my_txt", this.getNextHighestDepth(), 10, 10, 400, 22); my_txt.html = true;

my_txt.htmlText = "<b>Remember to always update the help panel.</b>";

trace("htmlText: "+my_txt.htmlText);

trace("text: "+my_txt.text);

/* output:

htmlText: <P ALIGN="LEFT"><FONT FACE="Times New Roman" SIZE="12"

COLOR="#000000"><B>Remember to always update your help panel.</B></FONT></P> text: Remember to always update your help panel.

*/

See also

TextField.htmlText

928 Chapter 2: ActionScript Language Reference

property is then used to resize the text field, and the new height and width will also be displayed

in the Output panel

this.createTextField("my_txt", 99, 10, 10, 100, 300);

my_txt.text = "Sample text";

trace("textHeight: "+my_txt.textHeight+", textWidth: "+my_txt.textWidth); trace("_height: "+my_txt._height+", _width: "+my_txt._width+"\n");

my_txt.autoSize = true;

trace("after my_txt.autoSize = true;");

trace("_height: "+my_txt._height+", _width: "+my_txt._width);

Which outputs the following information:

930 Chapter 2: ActionScript Language Reference

Example

The following example creates two text fields: username_txt and password_txt Text is entered into both text fields; however, password_txt has the password property set to true Therefore, the characters display as asterisks instead of as characters in the password_txt field

this.createTextField("username_txt", this.getNextHighestDepth(), 10, 10, 100, 22);

When you test this example, the URL of the SWF file you’re testing, and the file called

best_flash_ever.swf are displayed in the Output panel

932 Chapter 2: ActionScript Language Reference

The following example creates a text field called my_txt and associates the variable today_date

with the text field When you change the variable today_date, then the text that displays in

my_txt updates

this.createTextField("my_txt", 1, 10, 10, 200, 22);

my_txt.variable = "today_date";

var today_date:Date = new Date();

var date_interval:Number = setInterval(updateDate, 500);

function updateDate():Void {

today_date = new Date();

}

934 Chapter 2: ActionScript Language Reference

The following example creates two text fields that you can use to change the width and height of

a third text field on the Stage Add the following ActionScript to a FLA or AS file

this.createTextField("my_txt", this.getNextHighestDepth(), 10, 40, 160, 120); my_txt.background = true;

Property; a Boolean value that indicates if the text field has word wrap If the value of wordWrap is

true, the text field has word wrap; if the value is false, the text field does not have word wrap

936 Chapter 2: ActionScript Language Reference

Property; an integer that sets the x coordinate of a text field relative to the local coordinates of the

parent movie clip If a text field is on the main Timeline, then its coordinate system refers to the upper left corner of the Stage as (0, 0) If the text field is inside a movie clip that has

transformations, the text field is in the local coordinate system of the enclosing movie clip Thus, for a movie clip rotated 90º counterclockwise, the enclosed text field inherits a coordinate system that is rotated 90º counterclockwise The text field’s coordinates refer to the registration point position

Example

The following example creates a text field wherever you click the mouse When it creates a text

field, that field displays the current x and y coordinates of the text field.

this.createTextField("coords_txt", this.getNextHighestDepth(), 0, 0, 60, 22); coords_txt.autoSize = true;

this.createTextField("mouse_txt", this.getNextHighestDepth(), 10, 10, 200, 22);

938 Chapter 2: ActionScript Language Reference

Property; the y coordinate of a text field relative to the local coordinates of the parent movie clip

If a text field is in the main Timeline, then its coordinate system refers to the upper left corner of the Stage as (0, 0) If the text field is inside another movie clip that has transformations, the text field is in the local coordinate system of the enclosing movie clip Thus, for a movie clip rotated 90º counterclockwise, the enclosed text field inherits a coordinate system that is rotated 90º counterclockwise The text field’s coordinates refer to the registration point position

940 Chapter 2: ActionScript Language Reference