javascript - 获取相对于 jQuery 对话框窗口而不是视口(viewport)的鼠标坐标？

Question

我有以下代码负责显示工具提示。我对这段代码不满意有两个原因:

• 我使用 pageXOffset 和 pageYOffset“魔数(Magic Number)”来纠正每个浏览器的视觉状态。
• 对话窗口必须保持静止，数字才正确。

我已经尝试绑定(bind)到对话框窗口的 mousemove 事件而不是文档。结果与我当前绑定(bind)到文档的 mousemove 的实现相同。

var shouldDisplay = false;
$(document).mousemove(AdjustToolTipPosition);

function DisplayTooltip(tooltip_text) {
    shouldDisplay = (tooltip_text != "") ? true : false;
    if (shouldDisplay) {
        $('#CustomTooltip').html(tooltip_text);
        $('#CustomTooltip').show();
    }
    else {
        //Sometimes the tooltip hasn't finished fading in before we ask to hide it. This causes it to hide, then fade back in.
        $('#CustomTooltip').hide();
    }
}

function AdjustToolTipPosition(e) {
    if (shouldDisplay) {
        //msie e.page event should be standardizes, but seems to go awry when working inside of a modal window.
        var pageYOffset = $.browser.msie ? 260 : 572; //-314
        var pageXOffset = $.browser.msie ? 474 : 160; //+314

        $('#CustomTooltip').css('top', e.pageY - pageYOffset + 'px');
        var offsetLeft = e.pageX - pageXOffset;
        var isOutsideViewport = $("#HistoricalChartDialog").width() - $("#CustomTooltip").width() - offsetLeft < 0;

        //Prevent the tooltip from going off the screen by changing the offset when it would go off screen.
        if (isOutsideViewport) {
            offsetLeft = $("#HistoricalChartDialog").width() - $("#CustomTooltip").width();
        }

        $('#CustomTooltip').css('left', offsetLeft + 'px');
    }
}

// Initialize the Historical Chart dialog.        
$('#HistoricalChartDialog').dialog({
    autoOpen: false,
    buttons: {
        'Close': function() {
            $(this).dialog('close');
        }
    },
    hide: 'fold',
    modal: true,
    draggable: false,
    resizable: false,
    position: 'center',
    title: 'Historical Charts',
    width: 700,
    height: 475
});

我为此提供了 jQuery 对话框初始化器。工具提示仅显示在此对话框窗口内——但坐标适用于整个页面。是否可以检索相对于对话框窗口的坐标，以便我可以利用 jQuery 的 mousemove 将坐标与 pageX 和 pageY 属性标准化这一事实？

编辑解决方案:

//Seperate file because the offsets are different for the image under MVC.
var shouldDisplay = false;
$("#HistoricalChartDialog").mousemove(AdjustToolTipPosition);

function DisplayTooltip(tooltip_text) {
    shouldDisplay = (tooltip_text != "") ? true : false;
    if (shouldDisplay) {
        $('#CustomTooltip').html(tooltip_text);
        $('#CustomTooltip').show();
    }
    else {
        //Sometimes the tooltip hasn't finished fading in before we ask to hide it. This causes it to hide, then fade back in.
        $('#CustomTooltip').hide();
    }
}

function AdjustToolTipPosition(e) {
    if (shouldDisplay) {
        var xPos = e.pageX - $(this).closest('.ui-dialog').offset().left + 15;
        var widthDifference = $(this).width() - $("#CustomTooltip").width();
        //Prevent the tooltip from going off the screen by changing the offset when it would go off screen.
        xPos = (widthDifference - xPos < 0) ? widthDifference : xPos;
        $('#CustomTooltip').css('left', xPos + 'px');

        var yPos = e.pageY - $(this).closest('.ui-dialog').offset().top - 10;
        $('#CustomTooltip').css('top', yPos + 'px');
    }
}

Answer 1

要获取鼠标相对于特定 div(而不是视口(viewport))的位置，您需要 eventX/Y 并减去 div 的左/顶部位置:

$("#example").mousemove(function(e) {
    var xPos = e.pageX - $(this).position().left;
    var yPos = e.pageY - $(this).position().top;
    $("#pos").text("x: " + xPos + " / y: " + yPos);
});

Example fiddle

根据您的示例，这应该可行。不过，您可能需要查看您的 isOutsideViewport 逻辑。

function AdjustToolTipPosition(e) {
    if (shouldDisplay) {
        var xPos = e.pageX - $(this).position().left;
        var yPos = e.pageY - $(this).position().top;

        var isOutsideViewport = $("#HistoricalChartDialog").width() - $("#CustomTooltip").width() - xPos < 0;
        if (isOutsideViewport) {
            offsetLeft = $("#HistoricalChartDialog").width() - $("#CustomTooltip").width();
        }

        $('#CustomTooltip').css({
            'top': yPos + 'px',
            'left': xPos + 'px'
        });
    }
}