// ========================================================================== // Project: SproutCore - JavaScript Application Framework // Copyright: ©2006-2011 Strobe Inc. and contributors. // Portions ©2008-2011 Apple Inc. All rights reserved. // License: Licensed under MIT license (see license.js) // ==========================================================================

/**

@class

Displays a progress bar.  You can display both a defined and an
indeterminate progressbar.  The progress bar itself is designed to be styled
using CSS classes with the following structure:

    <div class="sc-progress-view"><div class="inner"></div></div>

The outer can form the boundary of the bar while the inner will be adjusted
to fit the percentage of the progress.

Creating a ProgressView accepts a number of properties, for example:

    progressView: SC.ProgressView.design({
      value: 50,
      minimum: 0,
      maximum: 100,
      isIndeterminate: NO,
      isEnabled: YES
    })

@extends SC.View
@extends SC.Control
@since SproutCore 1.0

*/ SC.ProgressView = SC.View.extend(SC.Control, /** @scope SC.ProgressView.prototype */{

/**
  @type Array
  @default ['sc-progress-view']
  @see SC.View#classNames
*/
classNames: ['sc-progress-view'],

/**
  @type Array
  @default ['displayValue', 'ariaValue', 'minimum', 'maximum', 'isIndeterminate', 'isRunning', 'isVisibleInWindow']
  @see SC.View#displayProperties
*/
displayProperties: ['displayValue', 'ariaValue', 'minimum', 'maximum', 'isIndeterminate', 'isRunning', 'isVisibleInWindow'],

/**
  @type String
  @default 'progressRenderDelegate'
*/
renderDelegateName: 'progressRenderDelegate',

// ........................................
// PROPERTIES
//

/**
  Bind this to the current value of the progress bar.  Note that by default
  an empty value will disable the progress bar and a multiple value will make
  it indeterminate.

  @type Number
  @default 0.50
*/
value: 0.50,

/** @private */
valueBindingDefault: SC.Binding.single().notEmpty(),

/**
  @field
  @type Number
  @observes value
  @observes maximum
  @observes minimum
*/
displayValue: function(){
  var minimum = this.get('minimum') || 0.0,
      maximum = this.get('maximum') || 1.0,
      value = this.get('value') || 0.0;

  // Percent value.
  value = (value - minimum) / (maximum - minimum);

  if (isNaN(value)) value = 0.0;
  // cannot be smaller then minimum
  if (value < 0.0) value = 0.0;
  // cannot be larger then maximum
  if (value > 1.0) value = 1.0;

  return value;
}.property('value', 'maximum', 'minimum').cacheable(),

/**
  The WAI-ARIA role for progress view.

  @type String
  @default 'progressbar'
  @readOnly
*/
ariaRole: 'progressbar',

/**
  The WAI-ARIA value for the progress view. This value will be passed to any
  rendering code as-is, not converted into percentages, etc. It is computed
  based on the original value property.

  @property
*/
ariaValue: function() {
  return this.get('value');
}.property('value').cacheable(),

/**
  The minimum value of the progress.

  @type Number
  @default 0
*/
minimum: 0,

/** @private */
minimumBindingDefault: SC.Binding.single().notEmpty(),

/**
  Optionally specify the key used to extract the minimum progress value
  from the content object.  If this is set to null then the minimum value
  will not be derived from the content object.

  @type String
  @default null
*/
contentMinimumKey: null,

/**
  The maximum value of the progress bar.

  @type Number
  @default 1.0
*/
maximum: 1.0,

/** @private */
maximumBindingDefault: SC.Binding.single().notEmpty(),

/**
  Optionally specify the key used to extract the maximum progress value
  from the content object.  If this is set to null then the maximum value
  will not be derived from the content object.

  @type String
  @default null
*/
contentMaximumKey: null,

/**
  Set to true if the item in progress is indeterminate.  This may be
  overridden by the actual value.

  @type Boolean
  @default NO
*/
isIndeterminate: NO,

/** @private */
isIndeterminateBindingDefault: SC.Binding.bool(),

/**
  Set to YES when the process is currently running.  This will cause the
  progress bar to animate, especially if it is indeterminate.

  @type Boolean
  @default NO
*/
isRunning: NO,

/** @private */
isRunningBindingDefault: SC.Binding.bool(),

/**
  Optionally specify the key used to extract the isIndeterminate value
  from the content object.  If this is set to null then the isIndeterminate
  value will not be derived from the content object.

  @type String
  @default null
*/
contentIsIndeterminateKey: null,

// ........................................
// INTERNAL SUPPORT
//

/** @private */
contentPropertyDidChange: function(target, key) {
  var content = this.get('content');
  this.beginPropertyChanges()
    .updatePropertyFromContent('value', key, 'contentValueKey', content)
    .updatePropertyFromContent('minimum', key, 'contentMinimumKey', content)
    .updatePropertyFromContent('maximum', key, 'contentMaximumKey', content)
    .updatePropertyFromContent('isIndeterminate', key, 'contentIsIndeterminateKey', content)
  .endPropertyChanges();
},

/** @private */
didCreateLayer: function() {
  // When using the JavaScript animation, we cannot start until the layer is
  // created.  Then if we are indeterminate, running and visible in the
  // window already, start animating.
  if (this.get('isIndeterminate') && this.get('isRunning') && this.get('isVisibleInWindow')) {
    this.displayDidChange();
  }
}

});