Files
openlayers/float-no-zero/closure-library/closure/goog/ui/keyboardshortcuthandler.js
2014-03-07 10:55:12 +01:00

1018 lines
33 KiB
JavaScript

// 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 Generic keyboard shortcut handler.
*
* @author eae@google.com (Emil A Eklund)
* @see ../demos/keyboardshortcuts.html
*/
goog.provide('goog.ui.KeyboardShortcutEvent');
goog.provide('goog.ui.KeyboardShortcutHandler');
goog.provide('goog.ui.KeyboardShortcutHandler.EventType');
goog.require('goog.Timer');
goog.require('goog.events');
goog.require('goog.events.Event');
goog.require('goog.events.EventTarget');
goog.require('goog.events.EventType');
goog.require('goog.events.KeyCodes');
goog.require('goog.events.KeyNames');
goog.require('goog.object');
goog.require('goog.userAgent');
/**
* Component for handling keyboard shortcuts. A shortcut is registered and bound
* to a specific identifier. Once the shortcut is triggered an event is fired
* with the identifier for the shortcut. This allows keyboard shortcuts to be
* customized without modifying the code that listens for them.
*
* Supports keyboard shortcuts triggered by a single key, a stroke stroke (key
* plus at least one modifier) and a sequence of keys or strokes.
*
* @param {goog.events.EventTarget|EventTarget} keyTarget Event target that the
* key event listener is attached to, typically the applications root
* container.
* @constructor
* @extends {goog.events.EventTarget}
*/
goog.ui.KeyboardShortcutHandler = function(keyTarget) {
goog.events.EventTarget.call(this);
/**
* Registered keyboard shortcuts tree. Stored as a map with the keyCode and
* modifier(s) as the key and either a list of further strokes or the shortcut
* task identifier as the value.
* @type {Object}
* @see #makeKey_
* @private
*/
this.shortcuts_ = {};
/**
* List of the last sequence of strokes. Object contains time last key was
* pressed and an array of strokes, represented by numeric value.
* @type {Object}
* @private
*/
this.lastKeys_ = {
strokes: [],
time: 0
};
/**
* List of numeric key codes for keys that are safe to always regarded as
* shortcuts, even if entered in a textarea or input field.
* @type {Object}
* @private
*/
this.globalKeys_ = goog.object.createSet(
goog.ui.KeyboardShortcutHandler.DEFAULT_GLOBAL_KEYS_);
/**
* List of input types that should only accept ENTER as a shortcut.
* @type {Object}
* @private
*/
this.textInputs_ = goog.object.createSet(
goog.ui.KeyboardShortcutHandler.DEFAULT_TEXT_INPUTS_);
/**
* Whether to always prevent the default action if a shortcut event is fired.
* @type {boolean}
* @private
*/
this.alwaysPreventDefault_ = true;
/**
* Whether to always stop propagation if a shortcut event is fired.
* @type {boolean}
* @private
*/
this.alwaysStopPropagation_ = false;
/**
* Whether to treat all shortcuts as if they had been passed
* to setGlobalKeys().
* @type {boolean}
* @private
*/
this.allShortcutsAreGlobal_ = false;
/**
* Whether to treat shortcuts with modifiers as if they had been passed
* to setGlobalKeys(). Ignored if allShortcutsAreGlobal_ is true. Applies
* only to form elements (not content-editable).
* @type {boolean}
* @private
*/
this.modifierShortcutsAreGlobal_ = true;
this.initializeKeyListener(keyTarget);
};
goog.inherits(goog.ui.KeyboardShortcutHandler, goog.events.EventTarget);
/**
* Maximum allowed delay, in milliseconds, allowed between the first and second
* key in a key sequence.
* @type {number}
*/
goog.ui.KeyboardShortcutHandler.MAX_KEY_SEQUENCE_DELAY = 1500; // 1.5 sec
/**
* Bit values for modifier keys.
* @enum {number}
*/
goog.ui.KeyboardShortcutHandler.Modifiers = {
NONE: 0,
SHIFT: 1,
CTRL: 2,
ALT: 4,
META: 8
};
/**
* Keys marked as global by default.
* @type {Array.<goog.events.KeyCodes>}
* @private
*/
goog.ui.KeyboardShortcutHandler.DEFAULT_GLOBAL_KEYS_ = [
goog.events.KeyCodes.ESC,
goog.events.KeyCodes.F1,
goog.events.KeyCodes.F2,
goog.events.KeyCodes.F3,
goog.events.KeyCodes.F4,
goog.events.KeyCodes.F5,
goog.events.KeyCodes.F6,
goog.events.KeyCodes.F7,
goog.events.KeyCodes.F8,
goog.events.KeyCodes.F9,
goog.events.KeyCodes.F10,
goog.events.KeyCodes.F11,
goog.events.KeyCodes.F12,
goog.events.KeyCodes.PAUSE
];
/**
* Text input types to allow only ENTER shortcuts.
* Web Forms 2.0 for HTML5: Section 4.10.7 from 29 May 2012.
* @type {Array.<string>}
* @private
*/
goog.ui.KeyboardShortcutHandler.DEFAULT_TEXT_INPUTS_ = [
'color',
'date',
'datetime',
'datetime-local',
'email',
'month',
'number',
'password',
'search',
'tel',
'text',
'time',
'url',
'week'
];
/**
* Events.
* @enum {string}
*/
goog.ui.KeyboardShortcutHandler.EventType = {
SHORTCUT_TRIGGERED: 'shortcut',
SHORTCUT_PREFIX: 'shortcut_'
};
/**
* Cache for name to key code lookup.
* @type {Object}
* @private
*/
goog.ui.KeyboardShortcutHandler.nameToKeyCodeCache_;
/**
* Target on which to listen for key events.
* @type {goog.events.EventTarget|EventTarget}
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.keyTarget_;
/**
* Due to a bug in the way that Gecko v1.8 on Mac handles
* cut/copy/paste key events using the meta key, it is necessary to
* fake the keydown for the action key (C,V,X) by capturing it on keyup.
* Because users will often release the meta key a slight moment
* before they release the action key, we need this variable that will
* store whether the meta key has been released recently.
* It will be cleared after a short delay in the key handling logic.
* @type {boolean}
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.metaKeyRecentlyReleased_;
/**
* Whether a key event is a printable-key event. Windows uses ctrl+alt
* (alt-graph) keys to type characters on European keyboards. For such keys, we
* cannot identify whether these keys are used for typing characters when
* receiving keydown events. Therefore, we set this flag when we receive their
* respective keypress events and fire shortcut events only when we do not
* receive them.
* @type {boolean}
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.isPrintableKey_;
/**
* Static method for getting the key code for a given key.
* @param {string} name Name of key.
* @return {number} The key code.
*/
goog.ui.KeyboardShortcutHandler.getKeyCode = function(name) {
// Build reverse lookup object the first time this method is called.
if (!goog.ui.KeyboardShortcutHandler.nameToKeyCodeCache_) {
var map = {};
for (var key in goog.events.KeyNames) {
map[goog.events.KeyNames[key]] = key;
}
goog.ui.KeyboardShortcutHandler.nameToKeyCodeCache_ = map;
}
// Check if key is in cache.
return goog.ui.KeyboardShortcutHandler.nameToKeyCodeCache_[name];
};
/**
* Sets whether to always prevent the default action when a shortcut event is
* fired. If false, the default action is prevented only if preventDefault is
* called on either of the corresponding SHORTCUT_TRIGGERED or SHORTCUT_PREFIX
* events. If true, the default action is prevented whenever a shortcut event
* is fired. The default value is true.
* @param {boolean} alwaysPreventDefault Whether to always call preventDefault.
*/
goog.ui.KeyboardShortcutHandler.prototype.setAlwaysPreventDefault = function(
alwaysPreventDefault) {
this.alwaysPreventDefault_ = alwaysPreventDefault;
};
/**
* Returns whether the default action will always be prevented when a shortcut
* event is fired. The default value is true.
* @see #setAlwaysPreventDefault
* @return {boolean} Whether preventDefault will always be called.
*/
goog.ui.KeyboardShortcutHandler.prototype.getAlwaysPreventDefault = function() {
return this.alwaysPreventDefault_;
};
/**
* Sets whether to always stop propagation for the event when fired. If false,
* the propagation is stopped only if stopPropagation is called on either of the
* corresponding SHORT_CUT_TRIGGERED or SHORTCUT_PREFIX events. If true, the
* event is prevented from propagating beyond its target whenever it is fired.
* The default value is false.
* @param {boolean} alwaysStopPropagation Whether to always call
* stopPropagation.
*/
goog.ui.KeyboardShortcutHandler.prototype.setAlwaysStopPropagation = function(
alwaysStopPropagation) {
this.alwaysStopPropagation_ = alwaysStopPropagation;
};
/**
* Returns whether the event will always be stopped from propagating beyond its
* target when a shortcut event is fired. The default value is false.
* @see #setAlwaysStopPropagation
* @return {boolean} Whether stopPropagation will always be called.
*/
goog.ui.KeyboardShortcutHandler.prototype.getAlwaysStopPropagation =
function() {
return this.alwaysStopPropagation_;
};
/**
* Sets whether to treat all shortcuts (including modifier shortcuts) as if the
* keys had been passed to the setGlobalKeys function.
* @param {boolean} allShortcutsGlobal Whether to treat all shortcuts as global.
*/
goog.ui.KeyboardShortcutHandler.prototype.setAllShortcutsAreGlobal = function(
allShortcutsGlobal) {
this.allShortcutsAreGlobal_ = allShortcutsGlobal;
};
/**
* Returns whether all shortcuts (including modifier shortcuts) are treated as
* if the keys had been passed to the setGlobalKeys function.
* @see #setAllShortcutsAreGlobal
* @return {boolean} Whether all shortcuts are treated as globals.
*/
goog.ui.KeyboardShortcutHandler.prototype.getAllShortcutsAreGlobal =
function() {
return this.allShortcutsAreGlobal_;
};
/**
* Sets whether to treat shortcuts with modifiers as if the keys had been
* passed to the setGlobalKeys function. Ignored if you have called
* setAllShortcutsAreGlobal(true). Applies only to form elements (not
* content-editable).
* @param {boolean} modifierShortcutsGlobal Whether to treat shortcuts with
* modifiers as global.
*/
goog.ui.KeyboardShortcutHandler.prototype.setModifierShortcutsAreGlobal =
function(modifierShortcutsGlobal) {
this.modifierShortcutsAreGlobal_ = modifierShortcutsGlobal;
};
/**
* Returns whether shortcuts with modifiers are treated as if the keys had been
* passed to the setGlobalKeys function. Ignored if you have called
* setAllShortcutsAreGlobal(true). Applies only to form elements (not
* content-editable).
* @see #setModifierShortcutsAreGlobal
* @return {boolean} Whether shortcuts with modifiers are treated as globals.
*/
goog.ui.KeyboardShortcutHandler.prototype.getModifierShortcutsAreGlobal =
function() {
return this.modifierShortcutsAreGlobal_;
};
/**
* Registers a keyboard shortcut.
* @param {string} identifier Identifier for the task performed by the keyboard
* combination. Multiple shortcuts can be provided for the same
* task by specifying the same identifier.
* @param {...(number|string|Array.<number>)} var_args See below.
*
* param {number} keyCode Numeric code for key
* param {number=} opt_modifiers Bitmap indicating required modifier keys.
* goog.ui.KeyboardShortcutHandler.Modifiers.SHIFT, CONTROL,
* ALT, or META.
*
* The last two parameters can be repeated any number of times to create a
* shortcut using a sequence of strokes. Instead of varagrs the second parameter
* could also be an array where each element would be ragarded as a parameter.
*
* A string representation of the shortcut can be supplied instead of the last
* two parameters. In that case the method only takes two arguments, the
* identifier and the string.
*
* Examples:
* g registerShortcut(str, G_KEYCODE)
* Ctrl+g registerShortcut(str, G_KEYCODE, CTRL)
* Ctrl+Shift+g registerShortcut(str, G_KEYCODE, CTRL | SHIFT)
* Ctrl+g a registerShortcut(str, G_KEYCODE, CTRL, A_KEYCODE)
* Ctrl+g Shift+a registerShortcut(str, G_KEYCODE, CTRL, A_KEYCODE, SHIFT)
* g a registerShortcut(str, G_KEYCODE, NONE, A_KEYCODE)
*
* Examples using string representation for shortcuts:
* g registerShortcut(str, 'g')
* Ctrl+g registerShortcut(str, 'ctrl+g')
* Ctrl+Shift+g registerShortcut(str, 'ctrl+shift+g')
* Ctrl+g a registerShortcut(str, 'ctrl+g a')
* Ctrl+g Shift+a registerShortcut(str, 'ctrl+g shift+a')
* g a registerShortcut(str, 'g a').
*/
goog.ui.KeyboardShortcutHandler.prototype.registerShortcut = function(
identifier, var_args) {
// Add shortcut to shortcuts_ tree
goog.ui.KeyboardShortcutHandler.setShortcut_(
this.shortcuts_, this.interpretStrokes_(1, arguments), identifier);
};
/**
* Unregisters a keyboard shortcut by keyCode and modifiers or string
* representation of sequence.
*
* param {number} keyCode Numeric code for key
* param {number=} opt_modifiers Bitmap indicating required modifier keys.
* goog.ui.KeyboardShortcutHandler.Modifiers.SHIFT, CONTROL,
* ALT, or META.
*
* The two parameters can be repeated any number of times to create a shortcut
* using a sequence of strokes.
*
* A string representation of the shortcut can be supplied instead see
* {@link #registerShortcut} for syntax. In that case the method only takes one
* argument.
*
* @param {...(number|string|Array.<number>)} var_args String representation, or
* array or list of alternating key codes and modifiers.
*/
goog.ui.KeyboardShortcutHandler.prototype.unregisterShortcut = function(
var_args) {
// Remove shortcut from tree
goog.ui.KeyboardShortcutHandler.setShortcut_(
this.shortcuts_, this.interpretStrokes_(0, arguments), null);
};
/**
* Verifies if a particular keyboard shortcut is registered already. It has
* the same interface as the unregistering of shortcuts.
*
* param {number} keyCode Numeric code for key
* param {number=} opt_modifiers Bitmap indicating required modifier keys.
* goog.ui.KeyboardShortcutHandler.Modifiers.SHIFT, CONTROL,
* ALT, or META.
*
* The two parameters can be repeated any number of times to create a shortcut
* using a sequence of strokes.
*
* A string representation of the shortcut can be supplied instead see
* {@link #registerShortcut} for syntax. In that case the method only takes one
* argument.
*
* @param {...(number|string|Array.<number>)} var_args String representation, or
* array or list of alternating key codes and modifiers.
* @return {boolean} Whether the specified keyboard shortcut is registered.
*/
goog.ui.KeyboardShortcutHandler.prototype.isShortcutRegistered = function(
var_args) {
return this.checkShortcut_(this.interpretStrokes_(0, arguments));
};
/**
* Parses the variable arguments for registerShortcut and unregisterShortcut.
* @param {number} initialIndex The first index of "args" to treat as
* variable arguments.
* @param {Object} args The "arguments" array passed
* to registerShortcut or unregisterShortcut. Please see the comments in
* registerShortcut for list of allowed forms.
* @return {Array.<Object>} The sequence of objects containing the
* keyCode and modifiers of each key in sequence.
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.interpretStrokes_ = function(
initialIndex, args) {
var strokes;
// Build strokes array from string.
if (goog.isString(args[initialIndex])) {
strokes = goog.ui.KeyboardShortcutHandler.parseStringShortcut(
args[initialIndex]);
// Build strokes array from arguments list or from array.
} else {
var strokesArgs = args, i = initialIndex;
if (goog.isArray(args[initialIndex])) {
strokesArgs = args[initialIndex];
i = 0;
}
strokes = [];
for (; i < strokesArgs.length; i += 2) {
strokes.push({
keyCode: strokesArgs[i],
modifiers: strokesArgs[i + 1]
});
}
}
return strokes;
};
/**
* Unregisters all keyboard shortcuts.
*/
goog.ui.KeyboardShortcutHandler.prototype.unregisterAll = function() {
this.shortcuts_ = {};
};
/**
* Sets the global keys; keys that are safe to always regarded as shortcuts,
* even if entered in a textarea or input field.
* @param {Array.<number>} keys List of keys.
*/
goog.ui.KeyboardShortcutHandler.prototype.setGlobalKeys = function(keys) {
this.globalKeys_ = goog.object.createSet(keys);
};
/**
* @return {Array.<string>} The global keys, i.e. keys that are safe to always
* regard as shortcuts, even if entered in a textarea or input field.
*/
goog.ui.KeyboardShortcutHandler.prototype.getGlobalKeys = function() {
return goog.object.getKeys(this.globalKeys_);
};
/** @override */
goog.ui.KeyboardShortcutHandler.prototype.disposeInternal = function() {
goog.ui.KeyboardShortcutHandler.superClass_.disposeInternal.call(this);
this.unregisterAll();
this.clearKeyListener();
};
/**
* Returns event type for a specific shortcut.
* @param {string} identifier Identifier for the shortcut task.
* @return {string} Theh event type.
*/
goog.ui.KeyboardShortcutHandler.prototype.getEventType =
function(identifier) {
return goog.ui.KeyboardShortcutHandler.EventType.SHORTCUT_PREFIX + identifier;
};
/**
* Builds stroke array from string representation of shortcut.
* @param {string} s String representation of shortcut.
* @return {Array.<Object>} The stroke array.
*/
goog.ui.KeyboardShortcutHandler.parseStringShortcut = function(s) {
// Normalize whitespace and force to lower case.
s = s.replace(/[ +]*\+[ +]*/g, '+').replace(/[ ]+/g, ' ').toLowerCase();
// Build strokes array from string, space separates strokes, plus separates
// individual keys.
var groups = s.split(' ');
var strokes = [];
for (var group, i = 0; group = groups[i]; i++) {
var keys = group.split('+');
var keyCode, modifiers = goog.ui.KeyboardShortcutHandler.Modifiers.NONE;
for (var key, j = 0; key = keys[j]; j++) {
switch (key) {
case 'shift':
modifiers |= goog.ui.KeyboardShortcutHandler.Modifiers.SHIFT;
continue;
case 'ctrl':
modifiers |= goog.ui.KeyboardShortcutHandler.Modifiers.CTRL;
continue;
case 'alt':
modifiers |= goog.ui.KeyboardShortcutHandler.Modifiers.ALT;
continue;
case 'meta':
modifiers |= goog.ui.KeyboardShortcutHandler.Modifiers.META;
continue;
}
keyCode = goog.ui.KeyboardShortcutHandler.getKeyCode(key);
break;
}
strokes.push({keyCode: keyCode, modifiers: modifiers});
}
return strokes;
};
/**
* Adds a key event listener that triggers {@link #handleKeyDown_} when keys
* are pressed.
* @param {goog.events.EventTarget|EventTarget} keyTarget Event target that the
* event listener should be attached to.
* @protected
*/
goog.ui.KeyboardShortcutHandler.prototype.initializeKeyListener =
function(keyTarget) {
this.keyTarget_ = keyTarget;
goog.events.listen(this.keyTarget_, goog.events.EventType.KEYDOWN,
this.handleKeyDown_, false, this);
// Firefox 2 on mac does not fire a keydown event in conjunction with a meta
// key if the action involves cutting/copying/pasting text.
// In this case we capture the keyup (which is fired) and fake as
// if the user had pressed the key to begin with.
if (goog.userAgent.MAC &&
goog.userAgent.GECKO && goog.userAgent.isVersionOrHigher('1.8')) {
goog.events.listen(this.keyTarget_, goog.events.EventType.KEYUP,
this.handleMacGeckoKeyUp_, false, this);
}
// Windows uses ctrl+alt keys (a.k.a. alt-graph keys) for typing characters
// on European keyboards (e.g. ctrl+alt+e for an an euro sign.) Unfortunately,
// Windows browsers except Firefox does not have any methods except listening
// keypress and keyup events to identify if ctrl+alt keys are really used for
// inputting characters. Therefore, we listen to these events and prevent
// firing shortcut-key events if ctrl+alt keys are used for typing characters.
if (goog.userAgent.WINDOWS && !goog.userAgent.GECKO) {
goog.events.listen(this.keyTarget_, goog.events.EventType.KEYPRESS,
this.handleWindowsKeyPress_, false, this);
goog.events.listen(this.keyTarget_, goog.events.EventType.KEYUP,
this.handleWindowsKeyUp_, false, this);
}
};
/**
* Handler for when a keyup event is fired in Mac FF2 (Gecko 1.8).
* @param {goog.events.BrowserEvent} e The key event.
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.handleMacGeckoKeyUp_ = function(e) {
// Due to a bug in the way that Gecko v1.8 on Mac handles
// cut/copy/paste key events using the meta key, it is necessary to
// fake the keydown for the action keys (C,V,X) by capturing it on keyup.
// This is because the keydown events themselves are not fired by the
// browser in this case.
// Because users will often release the meta key a slight moment
// before they release the action key, we need to store whether the
// meta key has been released recently to avoid "flaky" cutting/pasting
// behavior.
if (e.keyCode == goog.events.KeyCodes.MAC_FF_META) {
this.metaKeyRecentlyReleased_ = true;
goog.Timer.callOnce(function() {
this.metaKeyRecentlyReleased_ = false;
}, 400, this);
return;
}
var metaKey = e.metaKey || this.metaKeyRecentlyReleased_;
if ((e.keyCode == goog.events.KeyCodes.C ||
e.keyCode == goog.events.KeyCodes.X ||
e.keyCode == goog.events.KeyCodes.V) && metaKey) {
e.metaKey = metaKey;
this.handleKeyDown_(e);
}
};
/**
* Returns whether this event is possibly used for typing a printable character.
* Windows uses ctrl+alt (a.k.a. alt-graph) keys for typing characters on
* European keyboards. Since only Firefox provides a method that can identify
* whether ctrl+alt keys are used for typing characters, we need to check
* whether Windows sends a keypress event to prevent firing shortcut event if
* this event is used for typing characters.
* @param {goog.events.BrowserEvent} e The key event.
* @return {boolean} Whether this event is a possible printable-key event.
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.isPossiblePrintableKey_ =
function(e) {
return goog.userAgent.WINDOWS && !goog.userAgent.GECKO &&
e.ctrlKey && e.altKey && !e.shiftKey;
};
/**
* Handler for when a keypress event is fired on Windows.
* @param {goog.events.BrowserEvent} e The key event.
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.handleWindowsKeyPress_ = function(e) {
// When this keypress event consists of a printable character, set the flag to
// prevent firing shortcut key events when we receive the succeeding keyup
// event. We accept all Unicode characters except control ones since this
// keyCode may be a non-ASCII character.
if (e.keyCode > 0x20 && this.isPossiblePrintableKey_(e)) {
this.isPrintableKey_ = true;
}
};
/**
* Handler for when a keyup event is fired on Windows.
* @param {goog.events.BrowserEvent} e The key event.
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.handleWindowsKeyUp_ = function(e) {
// For possible printable-key events, try firing a shortcut-key event only
// when this event is not used for typing a character.
if (!this.isPrintableKey_ && this.isPossiblePrintableKey_(e)) {
this.handleKeyDown_(e);
}
};
/**
* Removes the listener that was added by link {@link #initializeKeyListener}.
* @protected
*/
goog.ui.KeyboardShortcutHandler.prototype.clearKeyListener = function() {
goog.events.unlisten(this.keyTarget_, goog.events.EventType.KEYDOWN,
this.handleKeyDown_, false, this);
if (goog.userAgent.MAC &&
goog.userAgent.GECKO && goog.userAgent.isVersionOrHigher('1.8')) {
goog.events.unlisten(this.keyTarget_, goog.events.EventType.KEYUP,
this.handleMacGeckoKeyUp_, false, this);
}
if (goog.userAgent.WINDOWS && !goog.userAgent.GECKO) {
goog.events.unlisten(this.keyTarget_, goog.events.EventType.KEYPRESS,
this.handleWindowsKeyPress_, false, this);
goog.events.unlisten(this.keyTarget_, goog.events.EventType.KEYUP,
this.handleWindowsKeyUp_, false, this);
}
this.keyTarget_ = null;
};
/**
* Adds or removes a stroke node to/from the given parent node.
* @param {Object} parent Parent node to add/remove stroke to/from.
* @param {Array.<Object>} strokes Array of strokes for shortcut.
* @param {?string} identifier Identifier for the task performed by shortcut or
* null to clear.
* @private
*/
goog.ui.KeyboardShortcutHandler.setShortcut_ = function(parent,
strokes,
identifier) {
var stroke = strokes.shift();
var key = goog.ui.KeyboardShortcutHandler.makeKey_(stroke.keyCode,
stroke.modifiers);
var node = parent[key];
if (node && identifier && (strokes.length == 0 || goog.isString(node))) {
throw Error('Keyboard shortcut conflicts with existing shortcut');
}
if (strokes.length) {
if (!node) {
node = parent[key] = {};
}
goog.ui.KeyboardShortcutHandler.setShortcut_(node,
strokes,
identifier);
}
else {
parent[key] = identifier;
}
};
/**
* Returns shortcut for a specific set of strokes.
* @param {Array.<number>} strokes Strokes array.
* @param {number=} opt_index Index in array to start with.
* @param {Object=} opt_list List to search for shortcut in.
* @return {string|Object} The shortcut.
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.getShortcut_ = function(
strokes, opt_index, opt_list) {
var list = opt_list || this.shortcuts_;
var index = opt_index || 0;
var stroke = strokes[index];
var node = list[stroke];
if (node && !goog.isString(node) && strokes.length - index > 1) {
return this.getShortcut_(strokes, index + 1, node);
}
return node;
};
/**
* Checks if a particular keyboard shortcut is registered.
* @param {Array.<Object>} strokes Strokes array.
* @return {boolean} True iff the keyboard is registred.
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.checkShortcut_ = function(strokes) {
var node = this.shortcuts_;
while (strokes.length > 0 && node) {
var stroke = strokes.shift();
var key = goog.ui.KeyboardShortcutHandler.makeKey_(stroke.keyCode,
stroke.modifiers);
node = node[key];
if (goog.isString(node)) {
return true;
}
}
return false;
};
/**
* Constructs key from key code and modifiers.
*
* The lower 8 bits are used for the key code, the following 3 for modifiers and
* the remaining bits are unused.
*
* @param {number} keyCode Numeric key code.
* @param {number} modifiers Required modifiers.
* @return {number} The key.
* @private
*/
goog.ui.KeyboardShortcutHandler.makeKey_ = function(keyCode, modifiers) {
// Make sure key code is just 8 bits and OR it with the modifiers left shifted
// 8 bits.
return (keyCode & 255) | (modifiers << 8);
};
/**
* Keypress handler.
* @param {goog.events.BrowserEvent} event Keypress event.
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.handleKeyDown_ = function(event) {
if (!this.isValidShortcut_(event)) {
return;
}
// For possible printable-key events, we cannot identify whether the events
// are used for typing characters until we receive respective keyup events.
// Therefore, we handle this event when we receive a succeeding keyup event
// to verify this event is not used for typing characters.
if (event.type == 'keydown' && this.isPossiblePrintableKey_(event)) {
this.isPrintableKey_ = false;
return;
}
var keyCode = goog.userAgent.GECKO ?
goog.events.KeyCodes.normalizeGeckoKeyCode(event.keyCode) :
event.keyCode;
var modifiers =
(event.shiftKey ? goog.ui.KeyboardShortcutHandler.Modifiers.SHIFT : 0) |
(event.ctrlKey ? goog.ui.KeyboardShortcutHandler.Modifiers.CTRL : 0) |
(event.altKey ? goog.ui.KeyboardShortcutHandler.Modifiers.ALT : 0) |
(event.metaKey ? goog.ui.KeyboardShortcutHandler.Modifiers.META : 0);
var stroke = goog.ui.KeyboardShortcutHandler.makeKey_(keyCode, modifiers);
// Check if any previous strokes where entered within the acceptable time
// period.
var node, shortcut;
var now = goog.now();
if (this.lastKeys_.strokes.length && now - this.lastKeys_.time <=
goog.ui.KeyboardShortcutHandler.MAX_KEY_SEQUENCE_DELAY) {
node = this.getShortcut_(this.lastKeys_.strokes);
} else {
this.lastKeys_.strokes.length = 0;
}
// Check if this stroke triggers a shortcut, either on its own or combined
// with previous strokes.
node = node ? node[stroke] : this.shortcuts_[stroke];
if (!node) {
node = this.shortcuts_[stroke];
this.lastKeys_.strokes = [];
}
// Check if stroke triggers a node.
if (node && goog.isString(node)) {
shortcut = node;
}
// Entered stroke(s) are a part of a sequence, store stroke and record
// time to allow the following stroke(s) to trigger the shortcut.
else if (node) {
this.lastKeys_.strokes.push(stroke);
this.lastKeys_.time = now;
// Prevent default action so find-as-you-type doesn't steal keyboard focus.
if (goog.userAgent.GECKO) {
event.preventDefault();
}
}
// No strokes for sequence, clear stored strokes.
else {
this.lastKeys_.strokes.length = 0;
}
// Dispatch keyboard shortcut event if a shortcut was triggered. In addition
// to the generic keyboard shortcut event a more specifc fine grained one,
// specific for the shortcut identifier, is fired.
if (shortcut) {
if (this.alwaysPreventDefault_) {
event.preventDefault();
}
if (this.alwaysStopPropagation_) {
event.stopPropagation();
}
var types = goog.ui.KeyboardShortcutHandler.EventType;
// Dispatch SHORTCUT_TRIGGERED event
var target = /** @type {Node} */ (event.target);
var triggerEvent = new goog.ui.KeyboardShortcutEvent(
types.SHORTCUT_TRIGGERED, shortcut, target);
var retVal = this.dispatchEvent(triggerEvent);
// Dispatch SHORTCUT_PREFIX_<identifier> event
var prefixEvent = new goog.ui.KeyboardShortcutEvent(
types.SHORTCUT_PREFIX + shortcut, shortcut, target);
retVal &= this.dispatchEvent(prefixEvent);
// The default action is prevented if 'preventDefault' was
// called on either event, or if a listener returned false.
if (!retVal) {
event.preventDefault();
}
// Clear stored strokes
this.lastKeys_.strokes.length = 0;
}
};
/**
* Checks if a given keypress event may be treated as a shortcut.
* @param {goog.events.BrowserEvent} event Keypress event.
* @return {boolean} Whether to attempt to process the event as a shortcut.
* @private
*/
goog.ui.KeyboardShortcutHandler.prototype.isValidShortcut_ = function(event) {
var keyCode = event.keyCode;
// Ignore Ctrl, Shift and ALT
if (keyCode == goog.events.KeyCodes.SHIFT ||
keyCode == goog.events.KeyCodes.CTRL ||
keyCode == goog.events.KeyCodes.ALT) {
return false;
}
var el = /** @type {Element} */ (event.target);
var isFormElement =
el.tagName == 'TEXTAREA' || el.tagName == 'INPUT' ||
el.tagName == 'BUTTON' || el.tagName == 'SELECT';
var isContentEditable = !isFormElement && (el.isContentEditable ||
(el.ownerDocument && el.ownerDocument.designMode == 'on'));
if (!isFormElement && !isContentEditable) {
return true;
}
// Always allow keys registered as global to be used (typically Esc, the
// F-keys and other keys that are not typically used to manipulate text).
if (this.globalKeys_[keyCode] || this.allShortcutsAreGlobal_) {
return true;
}
if (isContentEditable) {
// For events originating from an element in editing mode we only let
// global key codes through.
return false;
}
// Event target is one of (TEXTAREA, INPUT, BUTTON, SELECT).
// Allow modifier shortcuts, unless we shouldn't.
if (this.modifierShortcutsAreGlobal_ && (
event.altKey || event.ctrlKey || event.metaKey)) {
return true;
}
// Allow ENTER to be used as shortcut for text inputs.
if (el.tagName == 'INPUT' && this.textInputs_[el.type]) {
return keyCode == goog.events.KeyCodes.ENTER;
}
// Checkboxes, radiobuttons and buttons. Allow all but SPACE as shortcut.
if (el.tagName == 'INPUT' || el.tagName == 'BUTTON') {
return keyCode != goog.events.KeyCodes.SPACE;
}
// Don't allow any additional shortcut keys for textareas or selects.
return false;
};
/**
* Object representing a keyboard shortcut event.
* @param {string} type Event type.
* @param {string} identifier Task identifier for the triggered shortcut.
* @param {Node|goog.events.EventTarget} target Target the original key press
* event originated from.
* @extends {goog.events.Event}
* @constructor
*/
goog.ui.KeyboardShortcutEvent = function(type, identifier, target) {
goog.events.Event.call(this, type, target);
/**
* Task identifier for the triggered shortcut
* @type {string}
*/
this.identifier = identifier;
};
goog.inherits(goog.ui.KeyboardShortcutEvent, goog.events.Event);