1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
|
// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// This module implements the base attributes of the GuestView tags.
// -----------------------------------------------------------------------------
// Attribute object.
// Default implementation of a GuestView attribute.
function Attribute(name, view) {
this.dirty = false;
this.ignoreMutation = false;
this.name = name;
this.view = view;
this.defineProperty();
}
// Retrieves and returns the attribute's value.
Attribute.prototype.getValue = function() {
return this.view.element.getAttribute(this.name) || '';
};
// Retrieves and returns the attribute's value if it has been dirtied since
// the last time this method was called. Returns null otherwise.
Attribute.prototype.getValueIfDirty = function() {
if (!this.dirty)
return null;
this.dirty = false;
return this.getValue();
};
// Sets the attribute's value.
Attribute.prototype.setValue = function(value) {
this.view.element.setAttribute(this.name, value || '');
};
// Changes the attribute's value without triggering its mutation handler.
Attribute.prototype.setValueIgnoreMutation = function(value) {
this.ignoreMutation = true;
this.setValue(value);
this.ignoreMutation = false;
};
// Defines this attribute as a property on the view's element.
Attribute.prototype.defineProperty = function() {
$Object.defineProperty(this.view.element, this.name, {
get: function() {
return this.getValue();
}.bind(this),
set: function(value) {
this.setValue(value);
}.bind(this),
enumerable: true
});
};
// Called when the attribute's value changes.
Attribute.prototype.maybeHandleMutation = function(oldValue, newValue) {
if (this.ignoreMutation)
return;
this.dirty = true;
this.handleMutation(oldValue, newValue);
};
// Called when a change that isn't ignored occurs to the attribute's value.
Attribute.prototype.handleMutation = function(oldValue, newValue) {};
// Called when the view's element is attached to the DOM tree.
Attribute.prototype.attach = function() {};
// Called when the view's element is detached from the DOM tree.
Attribute.prototype.detach = function() {};
// -----------------------------------------------------------------------------
// BooleanAttribute object.
// An attribute that is treated as a Boolean.
function BooleanAttribute(name, view) {
Attribute.call(this, name, view);
}
BooleanAttribute.prototype.__proto__ = Attribute.prototype;
BooleanAttribute.prototype.getValue = function() {
return this.view.element.hasAttribute(this.name);
};
BooleanAttribute.prototype.setValue = function(value) {
if (!value) {
this.view.element.removeAttribute(this.name);
} else {
this.view.element.setAttribute(this.name, '');
}
};
// -----------------------------------------------------------------------------
// IntegerAttribute object.
// An attribute that is treated as an integer.
function IntegerAttribute(name, view) {
Attribute.call(this, name, view);
}
IntegerAttribute.prototype.__proto__ = Attribute.prototype;
IntegerAttribute.prototype.getValue = function() {
return parseInt(this.view.element.getAttribute(this.name)) || 0;
};
IntegerAttribute.prototype.setValue = function(value) {
this.view.element.setAttribute(this.name, parseInt(value) || 0);
};
// -----------------------------------------------------------------------------
// ReadOnlyAttribute object.
// An attribute that cannot be changed (externally). The only way to set it
// internally is via |setValueIgnoreMutation|.
function ReadOnlyAttribute(name, view) {
Attribute.call(this, name, view);
}
ReadOnlyAttribute.prototype.__proto__ = Attribute.prototype;
ReadOnlyAttribute.prototype.handleMutation = function(oldValue, newValue) {
this.setValueIgnoreMutation(oldValue);
}
// -----------------------------------------------------------------------------
var GuestViewAttributes = {
Attribute: Attribute,
BooleanAttribute: BooleanAttribute,
IntegerAttribute: IntegerAttribute,
ReadOnlyAttribute: ReadOnlyAttribute
};
// Exports.
exports.$set('GuestViewAttributes', GuestViewAttributes);
|
