我希望能够使用箭头键浏览网页上的所有可聚焦元素。因此,当按下向下键时,焦点应转移到当前聚焦元素下方的可聚焦元素。您可以了解其他箭头键,当没有可移动的可聚焦元素时,焦点应该保持不变。
这是我到目前为止所得到的:
$(document).keydown(function(e){
if (e.keyCode == 37) { //left
var offset = $("*:focus").offset();
var allElements = $("#container").find('a[href], area[href], input:not([disabled]), select:not([disabled]), textarea:not([disabled]), button:not([disabled]), iframe, object, embed, *[tabindex], *[contenteditable]');
var arr = jQuery.makeArray(allElements);
var topLeft = offset.left
var minus = topLeft;
var currentElement = $("*:focus");
for(var i = 0; i < arr.length; i++)
{
if ( (arr[i].offset().left < offset.left) // This doesn't work for some reason
&& ((offset.left - arr[i].offset().left) < minus))
{
currentElement = arr[i];
minus = offset.left - arr[i].offset().left;
topLeft = arr[i].offset().left;
}
currentElement.focus();
}
alert( "left pressed" );
return false;
}
// Other Keys
});
这个想法是获得所有可聚焦的元素,而不是选择适合箭头和移位焦点的元素。
我无法让这段代码工作(它包含一个错误),而且我并不完全确定它会工作。
Thnx提前
[编辑]:我想我有点模糊。我不仅想要左右移动,而且还要上下移动。
答案 0 :(得分:24)
我会做的更简单。只需在应该具有此功能的对象中添加一个公共类(f.ex。“move”)并使用:
$(document).keydown(
function(e)
{
if (e.keyCode == 39) {
$(".move:focus").next().focus();
}
if (e.keyCode == 37) {
$(".move:focus").prev().focus();
}
}
);
参见示例:http://jsfiddle.net/uJ4PJ/
此代码很多更简单,希望能够提供您需要的所有功能。
只需确保控件的顺序正确,否则无效。
答案 1 :(得分:1)
预览 - http://jsfiddle.net/FehKh/;)
<强> HTML:强>
<a href='jqwja' class="focusable">jajaj</a>
<a href='jjaasd' class="focusable focused">jajasdaaj</a>
<a href='jjqwea' class="focusable">jajaacasj</a>
<input value='iddqd' name="DoomII" class="focusable" />
<强> JS:强>
// init
$('.focused').focus();
// actual code
$(document).keydown(function(e){
if (e.keyCode == 37) { // left
if($('.focused').prev('.focusable').length)
$('.focused').removeClass('focused').prev('.focusable').focus().addClass('focused');
}
if (e.keyCode == 39) { // right
if($('.focused').next('.focusable').length)
$('.focused').removeClass('focused').next('.focusable').focus().addClass('focused');
}
});
答案 2 :(得分:1)
经过多次试验和错误,我开发了这个有效的代码:
function navigate(origin, sens) {
var inputs = $('#form').find('input:enabled');
var index = inputs.index(origin);
index += sens;
if (index < 0) {
index = inputs.length - 1;
}
if (index > inputs.length - 1) {
index = 0;
}
inputs.eq(index).focus();
}
$('input').keydown(function(e) {
if (e.keyCode==37) {
navigate(e.target, -1);
}
if (e.keyCode==39) {
navigate(e.target, 1);
}
});
右箭头作为标签
左箭头作为班次选项卡
答案 3 :(得分:0)
通过检查一些文章并叠加流链接
来实现jQuery.fn.elementAfter = function(other) {
for(i = 0; i < this.length - 1; i++) {
if (this[i] == other) {
return jQuery(this[i + 1]);
}
}
return jQuery;
} ;
jQuery.fn.elementBefore = function(other) {
if (this.length > 0) {
for(i = 1; i < this.length; i++) {
if (this[i] == other) {
return jQuery(this[i - 1]);
}
}
}
return jQuery;
};
答案 4 :(得分:0)
这很好用
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
var model = {
circle1: { x: 200, y: 200 },
circle2: { x: 200, y: 200 }
};
var radius = 50;
function view(ctx, model) {
function circle(c) {
ctx.beginPath();
ctx.beginPath();
ctx.arc(c.x, c.y, radius, 0, 2 * Math.PI, true);
ctx.fillStyle = "#FF6A6A";
ctx.fill();
ctx.stroke();
}
// clear canvas
ctx.clearRect(0, 0, canvas.width, canvas.height);
circle(model.circle1);
circle(model.circle2);
}
function redraw() {
view(ctx, model);
}
redraw();
function getCircleForPosition(x, y) {
function intersect(a, b) {
var d2 = Math.pow(a.x - b.x, 2) + Math.pow(a.y - b.y, 2);
r2 = Math.pow(radius, 2);
return d2 < r2;
}
return [model.circle1, model.circle2].find(circle => intersect(circle, { x, y }));
}
canvas.addEventListener('mousedown', function(e) {
model.dragging = getCircleForPosition(e.pageX, e.pageY);
}, 0);
canvas.addEventListener('mouseup', function() {
model.dragging = undefined;
}, 0);
canvas.addEventListener('mousemove', function(e) {
if (model.dragging) {
model.dragging.x = e.pageX;
model.dragging.y = e.pageY;
redraw();
}
}, 0);
答案 5 :(得分:0)
以上解决方案均不适合我。这是我的。看起来很困难,但实际上非常容易。创建链接的array
,并使用数组index
更改焦点。 (我需要向上/向下箭头,因此键码不同)。它也可以与dynamicly
添加的链接一起使用(因为我需要这种方式,所以我使用on
)
$('#links_container').on("keydown", ".link",
function(e)
{
//start - list of <a>
var flag = false;
var smallMeni = document.getElementById('links_container');
var allElements2 = smallMeni.getElementsByTagName('a'); //.link
//end
//start - key down
if (e.keyCode == 40)
{
for (var i=0;i<allElements2.length;i++)
{
if(flag == true){
flag = false
allElements2[i].focus();
//alert(i)
}
else
{
if ( document.activeElement === allElements2[i] )
{
//alert(i);
flag = true;
}
}
}
}
//end
//start - key up
if (e.keyCode == 38)
{
for (var i=0;i<allElements2.length;i++)
{
if ( document.activeElement === allElements2[i] )
{
if (i>0)
{
allElements2[i-1].focus();
}
}
}
}
//alert(i);
}
);
答案 6 :(得分:0)
此库具有类似的实现:keyboard-navigator。
通过比较坐标获得下一个方向性节点来转移焦点。
但是您必须为要导航的所有节点(fromNodes)提供此功能。
getNextDirectionalNode = function (activeNode,fromNodes,direction,coordinatesDeviationFactor=0){
var filteredNodes = []
var indexOfReturningElem = 0;
if(direction == "down"){
for(var i=0; i<fromNodes.length; i++)
{
if( this.inDeviationRange(fromNodes[i].getBoundingClientRect().x,activeNode.getBoundingClientRect().x,coordinatesDeviationFactor) &&
(fromNodes[i].getBoundingClientRect().y > activeNode.getBoundingClientRect().y)
)
{
filteredNodes.push(fromNodes[i])
}
}
indexOfReturningElem = 0;
if( indexOfReturningElem >= 0 && (indexOfReturningElem <= filteredNodes.length-1) ){
return filteredNodes[indexOfReturningElem];
}
}
if(direction == "up"){
for(var i=0; i<fromNodes.length; i++)
{
if( this.inDeviationRange(fromNodes[i].getBoundingClientRect().x,activeNode.getBoundingClientRect().x,coordinatesDeviationFactor) &&
(fromNodes[i].getBoundingClientRect().y < activeNode.getBoundingClientRect().y)
)
{
filteredNodes.push(fromNodes[i])
}
}
indexOfReturningElem = filteredNodes.length - 1;
if( indexOfReturningElem >= 0 && (indexOfReturningElem <= filteredNodes.length-1) ){
return filteredNodes[indexOfReturningElem];
}
}
if(direction == "right"){
for(var i=0; i<fromNodes.length; i++)
{
if( this.inDeviationRange(fromNodes[i].getBoundingClientRect().y,activeNode.getBoundingClientRect().y,coordinatesDeviationFactor) &&
(fromNodes[i].getBoundingClientRect().x > activeNode.getBoundingClientRect().x)
)
{
filteredNodes.push(fromNodes[i])
}
}
indexOfReturningElem = 0;
if( indexOfReturningElem >= 0 && (indexOfReturningElem <= filteredNodes.length-1) ){
return filteredNodes[indexOfReturningElem];
}
}
if(direction == "left"){
for(var i=0; i<fromNodes.length; i++)
{
if( this.inDeviationRange(fromNodes[i].getBoundingClientRect().y,activeNode.getBoundingClientRect().y,coordinatesDeviationFactor) &&
(fromNodes[i].getBoundingClientRect().x < activeNode.getBoundingClientRect().x)
)
{
filteredNodes.push(fromNodes[i])
}
}
indexOfReturningElem = filteredNodes.length - 1;
if( indexOfReturningElem >= 0 && (indexOfReturningElem <= filteredNodes.length-1) ){
return filteredNodes[indexOfReturningElem];
}
}
return null;
}