Chartjs- 2 Doughnut Charts customized Tooltip

问题

i want to display some data in reactjs using Chartjs-2. For displaying my data i want a Doughnut Pie chart. When i use the specific pie chart it shows me like:

But the desired output should be something like this:

I have read from the documentation that i should edit the tooltip from the option but i cannot find the way to do this. Do you know how?

回答1:

You need to implement your custom tool tip in the chart options. You have to replace the html element style and size with the one you want.

var myPieChart = new Chart(ctx, {
    type: 'pie',
    data: data,
    options: {
        tooltips: {
            custom: function(tooltipModel) {
                // Tooltip Element
                var tooltipEl = document.getElementById('chartjs-tooltip');

                // Create element on first render
                if (!tooltipEl) {
                    tooltipEl = document.createElement('div');
                    tooltipEl.id = 'chartjs-tooltip';
                    tooltipEl.innerHTML = "<table></table>"
                    document.body.appendChild(tooltipEl);
                }

                // Hide if no tooltip
                if (tooltipModel.opacity === 0) {
                    tooltipEl.style.opacity = 0;
                    return;
                }

                // Set caret Position
                tooltipEl.classList.remove('above', 'below', 'no-transform');
                if (tooltipModel.yAlign) {
                    tooltipEl.classList.add(tooltipModel.yAlign);
                } else {
                    tooltipEl.classList.add('no-transform');
                }

                function getBody(bodyItem) {
                    return bodyItem.lines;
                }

                // Set Text
                if (tooltipModel.body) {
                    var titleLines = tooltipModel.title || [];
                    var bodyLines = tooltipModel.body.map(getBody);

                    var innerHtml = '<thead>';

                    titleLines.forEach(function(title) {
                        innerHtml += '<tr><th>' + title + '</th></tr>';
                    });
                    innerHtml += '</thead><tbody>';

                    bodyLines.forEach(function(body, i) {
                        var colors = tooltipModel.labelColors[i];
                        var style = 'background:' + colors.backgroundColor;
                        style += '; border-color:' + colors.borderColor;
                        style += '; border-width: 2px';
                        var span = '<span class="chartjs-tooltip-key" style="' + style + '"></span>';
                        innerHtml += '<tr><td>' + span + body + '</td></tr>';
                    });
                    innerHtml += '</tbody>';

                    var tableRoot = tooltipEl.querySelector('table');
                    tableRoot.innerHTML = innerHtml;
                }

                // `this` will be the overall tooltip
                var position = this._chart.canvas.getBoundingClientRect();

                // Display, position, and set styles for font
                tooltipEl.style.opacity = 1;
                tooltipEl.style.left = position.left + tooltipModel.caretX + 'px';
                tooltipEl.style.top = position.top + tooltipModel.caretY + 'px';
                tooltipEl.style.fontFamily = tooltipModel._fontFamily;
                tooltipEl.style.fontSize = tooltipModel.fontSize;
                tooltipEl.style.fontStyle = tooltipModel._fontStyle;
                tooltipEl.style.padding = tooltipModel.yPadding + 'px ' + tooltipModel.xPadding + 'px';
            }
        }
    }
});

来源：https://stackoverflow.com/questions/42696822/chartjs-2-doughnut-charts-customized-tooltip