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
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
// Copyright 2006 The Closure Library Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS-IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
/**
* @fileoverview Character counter widget implementation.
*
* @author eae@google.com (Emil A Eklund)
* @see ../demos/charcounter.html
*/
goog.provide('goog.ui.CharCounter');
goog.provide('goog.ui.CharCounter.Display');
goog.require('goog.dom');
goog.require('goog.events');
goog.require('goog.events.EventTarget');
goog.require('goog.events.InputHandler');
/**
* CharCounter widget. Counts the number of characters in a input field or a
* text box and displays the number of additional characters that may be
* entered before the maximum length is reached.
*
* @extends {goog.events.EventTarget}
* @param {HTMLInputElement|HTMLTextAreaElement} elInput Input or text area
* element to count the number of characters in. You can pass in null
* for this if you don't want to expose the number of chars remaining.
* @param {Element} elCount HTML element to display the remaining number of
* characters in.
* @param {number} maxLength The maximum length.
* @param {goog.ui.CharCounter.Display=} opt_displayMode Display mode for this
* char counter. Defaults to {@link goog.ui.CharCounter.Display.REMAINING}.
* @constructor
*/
goog.ui.CharCounter = function(elInput, elCount, maxLength, opt_displayMode) {
goog.events.EventTarget.call(this);
/**
* Input or text area element to count the number of characters in.
* @type {HTMLInputElement|HTMLTextAreaElement}
* @private
*/
this.elInput_ = elInput;
/**
* HTML element to display the remaining number of characters in.
* @type {Element}
* @private
*/
this.elCount_ = elCount;
/**
* The maximum length.
* @type {number}
* @private
*/
this.maxLength_ = maxLength;
/**
* The display mode for this char counter.
* @type {!goog.ui.CharCounter.Display}
* @private
*/
this.display_ = opt_displayMode || goog.ui.CharCounter.Display.REMAINING;
elInput.maxLength = maxLength;
/**
* The input handler that provides the input event.
* @type {goog.events.InputHandler}
* @private
*/
this.inputHandler_ = new goog.events.InputHandler(elInput);
goog.events.listen(this.inputHandler_,
goog.events.InputHandler.EventType.INPUT, this.onChange_, false, this);
this.checkLength_();
};
goog.inherits(goog.ui.CharCounter, goog.events.EventTarget);
/**
* Display mode for the char counter.
* @enum {number}
*/
goog.ui.CharCounter.Display = {
/** Widget displays the number of characters remaining (the default). */
REMAINING: 0,
/** Widget displays the number of characters entered. */
INCREMENTAL: 1
};
/**
* Sets the maximum length.
*
* @param {number} maxLength The maximum length.
*/
goog.ui.CharCounter.prototype.setMaxLength = function(maxLength) {
this.maxLength_ = maxLength;
this.elInput_.maxLength = maxLength;
this.checkLength_();
};
/**
* Returns the maximum length.
*
* @return {number} The maximum length.
*/
goog.ui.CharCounter.prototype.getMaxLength = function() {
return this.maxLength_;
};
/**
* Sets the display mode.
*
* @param {!goog.ui.CharCounter.Display} displayMode The display mode.
*/
goog.ui.CharCounter.prototype.setDisplayMode = function(displayMode) {
this.display_ = displayMode;
this.checkLength_();
};
/**
* Returns the display mode.
*
* @return {!goog.ui.CharCounter.Display} The display mode.
*/
goog.ui.CharCounter.prototype.getDisplayMode = function() {
return this.display_;
};
/**
* Change event handler for input field.
*
* @param {goog.events.BrowserEvent} event Change event.
* @private
*/
goog.ui.CharCounter.prototype.onChange_ = function(event) {
this.checkLength_();
};
/**
* Checks length of text in input field and updates the counter. Truncates text
* if the maximum lengths is exceeded.
*
* @private
*/
goog.ui.CharCounter.prototype.checkLength_ = function() {
var count = this.elInput_.value.length;
// There's no maxlength property for textareas so instead we truncate the
// text if it gets too long. It's also used to truncate the text in a input
// field if the maximum length is changed.
if (count > this.maxLength_) {
var scrollTop = this.elInput_.scrollTop;
var scrollLeft = this.elInput_.scrollLeft;
this.elInput_.value = this.elInput_.value.substring(0, this.maxLength_);
count = this.maxLength_;
this.elInput_.scrollTop = scrollTop;
this.elInput_.scrollLeft = scrollLeft;
}
if (this.elCount_) {
var incremental = this.display_ == goog.ui.CharCounter.Display.INCREMENTAL;
goog.dom.setTextContent(
this.elCount_,
/** @type {string} */(incremental ? count : this.maxLength_ - count));
}
};
/** @override */
goog.ui.CharCounter.prototype.disposeInternal = function() {
goog.ui.CharCounter.superClass_.disposeInternal.call(this);
delete this.elInput_;
this.inputHandler_.dispose();
this.inputHandler_ = null;
};
|
