Fixing the Resize Function in HTML Widgets: A Revised Implementation

Introduction

The resize function in the provided code seems to be incomplete and not functioning as expected. In this response, we will break down the issues with the current implementation and provide a revised version of the resize function that should work correctly.

Issues with the Current Implementation

The svg element is being appended multiple times when resizing the widget.
The dimensions of the new svg element are not being updated correctly.
There is no logic to re-render the widget’s content after a resize event.

Revised Resize Function

Here is a revised version of the resize function that addresses the issues mentioned above:

resize: function(width, height) {

    // Update the dimensions of the new svg element
    var dims = {
        width: width - margin.left - margin.right,
        height: height - margin.top - margin.bottom
    };

    // Update the xContinuous and y scales based on the new dimensions
    var xContinuous = d3.scaleLinear()
        .domain([distParams.min - 1, distParams.max + 1])
        .range([0, dims.width]);

    var y = d3.scaleLinear()
        .domain([0, 1])
        .range([dims.height, 0]);

    // Remove the old svg element and append a new one
    var oldSvg = d3.select(el).selectAll("svg").remove();
    var newSvg = oldSvg.append("svg")
        .attr("width", dims.width + margin.left + margin.right)
        .attr("height", dims.height + margin.top + margin.bottom);

    // Update the x and y axes
    var g = newSvg
        .append("g")
        .attr("transform", "translate(" + margin.left + "," + margin.top + ")");

    var xAxis = d3.axisBottom()
        .scale(xDiscrete);

    var yAxis = d3.axisLeft()
        .scale(y)
        .ticks(10)
        .tickFormat(d3.format(".0%"));

    g.append("g")
        .attr("class", "x axis")
        .attr("transform", "translate(0," + dims.height + ")")
        .call(xAxis);

    g.append("g")
        .attr("class", "y axis")
        .call(yAxis);

    // Update the areas and threshold line
    var areas = newSvg.selectAll(".area")
        .data(dataDiscrete)
        .enter().append("path")
            .attr("class", "area")
            .style("fill", function(d) { return d.color; })
            .attr("d", function(d, i) {
                let numPts = dataContinuousGroups[i].data.length - 2;
                var path = d3.path();
                path.moveTo(xDiscrete(d.x), y(0));
                for (j=0; j<numPts; j++) {
                    path.lineTo(xDiscrete(d.x) + j*xDiscrete.bandwidth()/(numPts-1), y(d.y));
                }
                path.lineTo(xDiscrete(d.x) + xDiscrete.bandwidth(), y(0));
                return path.toString();
            });

    var thresholdLine = newSvg.append("line")
        .attr("stroke", "black")
        .style("stroke-width", "1.5px")
        .style("stroke-dasharray", "5,5")
        .style("opacity", 1)
        .attr("x1", 0)
        .attr("y1", y(opts.threshold))
        .attr("x2", dims.width)
        .attr("y2", y(opts.threshold));

    // Re-render the widget's content
    areas.on('mouseover', tooltip.show)
        .on('mouseout', tooltip.hide);

    thresholdLine.transition()
        .duration(0)
        .delay(duration)
        .style("opacity", 1)
        .attr("y1", y(opts.threshold))
        .attr("y2", y(opts.threshold));

    g.select(".x").transition().duration(duration).call(xAxis);
    g.select(".y").transition().duration(duration).call(yAxis);

},

Conclusion

In this revised implementation, the resize function correctly updates the dimensions of the new svg element and re-renders the widget’s content after a resize event. This should fix the issues mentioned in the original code.

However, there are still some potential issues with this implementation:

The widget may not respond immediately to changes in size.
The resize function does not handle cases where the user resizes the window while the widget is being updated.
There is no logic to prevent the user from resizing the widget beyond its original dimensions.

To address these issues, additional modifications would be required.

Last modified on 2023-07-04

Fail to Resize HTML Widget?

Introduction

Issues with the Current Implementation

Revised Resize Function

Conclusion