Index of HOWTO guides
These guides take you through doing common tasks step-by-step. Think of them as mini-tutorials that accomplish a specific job.
- How to get transparent tickmarks using the canvas Line chart (see the demo svg-line-formidable.html in the download archive
This is actually one of the RGraph examples that are included in the download zip file. Normally getting transparent centers to your tickmarks is possible - but it wipes out the center of the tickmark in its entirety - including the background grid that sits behind it. This is an explanation of how, using dual canvas tags, you can get a transparent center to your tickmarks but with the background grid showing through.
- How to get rounded corners on a Bar chart
This HOWTO guide details how you can get rounded corners on your Bar chart. Previously this involved a substantial amount of custom code. Now though (as of version 6.01) it's just a case of specifying the
- How to create a chart without a browser using PhantomJS
This HOWTO guide has detailed instructions about how to use the PhantomJS tool to create your charts from the command line. PhantomJS is a Webkit based headless browser that runs from the command line. This means that you can use it to automate (via a scheduled task for example) the creation of charts for the purposes of making images of charts available for download to include in (for example) PDF documents.
- How to dynamically add points to your Line chart
This HOWTO guide shows you how you can add new points to your chart by simply clicking in the left or right margins. It consists of simply adding an event listener to the canvas tag and manipulating the arrays of the Line chart.
- How to get angled labels that follow the undulations of your line
This HOWTO guide shows you how to add custom labels to a Line chart that follow the undulations of the line itself - as well as having regular labels in the bottom margin of the chart.
- How to turn a label into a link
This document shows you how, when using the
textAccessibleoption, to turn one of your labels into a functioning link that you can click.
- How to create a Bar chart that's capable of multiple select
This HOWTO demonstrates how to add multiple select capabilities to your Bar chart. You could, for example, use this together with some AJAX code to pass information back and forth to the server about which bars are currently highlighted.
- How to create one-touch Line chart adjusting that's usable on touch devices
This HOWTO demonstrates how to go about creating an adjustable Line chart that doesn't use the built in adjusting functionality. This is so that the adjusting can be made to use a single touch - so it works well on touch based devices as well as mouse based computers.
- How to use repeating canvas patterns on your chart
This HOWTO shows you how you can use repeating seamless fill patterns in your chart(s) instead of solid colors or gradients. Patterns can enable you in place of solid colors.
- How to create a multi-chart scrolling effect with CSS transitions
Create a single large canvas to show multiple charts and scroll between them using CSS3 transitions. This can be an effective way of showing multiple charts but in a limited space.
- How to create a CSS3 transitions based switch effect
Create a CSS3 based switch effect for showing two charts in the same place. Using CSS transitions can also be a good way of using a smaller space and show multiple charts.
- How to use CSS3 transitions to save space
This HOWTO document shows you how to display four canvas tags using space of one and use CSS3 transitions to switch between them. Because it uses CSS to switch between the charts the scrolling is smooth.
- How to create a multi-chart scrolling effect with CSS transitions
Create a single large canvas to show multiple charts and scroll between them using CSS3 transitions. This changes the CSS top/left properties and uses CSS transitions to do the animation, but you just as easily use the jQuery
animate()function to do the animating.
- How to make a dynamic scrolling Line chart
Create a dynamically scrolling and updating Line chart. Scrolling Line charts can be used to great effect when monitoring a value (such as an attached device).
- How to use CSS3 transitions with your canvas tag
Use CSS3 transitions to create a zooming switch effect between two charts. As one chart zooms out, another then zooms in. This is another way of showing multiple charts in the space of one.
- How to use CSS3 gradients with your canvas tag
How you can use CSS3 gradients as the background on your canvas tag. This HOWTO document illustrates various different gradients that CSS can produce, some repeating and some not.
- How to make your line clickable using the isPointInStroke() function
Make whole lines clickable instead of just certain points along that line. This could be used to allow you to provide more information (via a popup for example) about a particular dataset.
- How to make your line clickable and then highlight the key
Make whole lines clickable and highlight the key at the same time. This uses the coordinates from a Line chart object to draw a drawing API Poly object over the lines and then, when the poly objects are clicked, highlights the key.
- How to use the
RGraph.text()function to add custom text to your charts. You can use two methods - the
RGraph.text()function as shown here or the drawing API text object. The
RGraph.text()function is the underlying function that's used by the drawing API text object.
- How to make a Contract/Expand transition effect
Create a switch effect between two canvas tags. Note that CSS3 transitions are smoother (example above). This is useful when you have multiple charts to display in a limited space.
- How to show a custom static Y axis
Create a Y axis that remains static whilst the canvas scrolls left and right. This can be used when you have a wide dataset that you still need to correlate closely with the scale.
- How to use CSS3 animations
How you can use, and examples of, CSS3 animations. The animations library here is an external one with a few new animations added. CSS animations are very smooth in appearance.
- How to use the new gradient syntax
Use the RGraph custom (and much simplified) gradient syntax. Gradients are an easy way to pretty up your charts. The gradient syntax that's shown here is far simpler to use than the standard canvas syntax.
- How to use custom tickmarks using the drawing API
Use the drawing API image object to show customised tickmarks. Because the drawing API image object is being used things such as events and tooltips can be added too.
- How to use the new dollar syntax for events
Use the new dollar syntax to add clickable areas to your chart. The dollar syntax makes adding the clickable areas to your charts very easy. There are
- How to display a Date/Time chart
Show a date/time chart line chart (but using the Scatter chart). This is actually an XY chart so for each point you will need an X value and a Y value. The X value is usually the date/time and the Y value is the numerical value.
- How to highlight a bar on your chart
How to highlight a bar on your chart using empty tooltips (so no tooltip is shown). This HOWTO guide also shows you how you can use the
clickevent to highlight the bar.
- How to debug your charts with Chrome
Make use of the Chrome developer tools to debug your charts and a video that shows you how to use them. This page also details some of the debug functions in RGraph that can help you if have trouble getting your charts working.
- How to get the original value from a click
How to get the original value from a click (in this case a Bar, Line and Pie chart). The code consists of an event listener that queries the data of the Pie chart object.
- How to create a combo Bar, Line and Pie chart
CombinedChartclass to make a combined Bar, Line and Pie chart. The full code is given on this page for the combined chart.
- How to use DOM1-style RGraph custom events
Use DOM1 style custom RGraph events (eg the tooltip event). This example uses the
drawevent in order to add highlighting to each bar on the chart.
- How to create a Gauge that updates a form
Different ways to update a form element when you're altering the Gauge chart. A number of different methods are shown and the value represented on the Gauge chart is used to update the form text element.
- How to use CSS 3D transforms
Use CSS 3D transformations in conjunction with your canvas tag to get a 3D effect. Remember that the 3D transformations are applied to your whole canvas tag. This example allows you to update the XYZ angles that are used.
- How to use images as tickmarks
Use images as your tickmarks when using the Line or Scatter charts. A custom function is used to load and position the image and the canvas.
- How to get crisp lines with no anti-aliasing
Achieve crisp lines on your canvas by applying a small anti-aliasing fix. This gives the single pixel width lines and it can also be used on any canvas - not just RGraph.
- How to create a bank of Gauge charts
Make a set of three adjustable or animated Gauge charts (using just one canvas). The Gauge charts can be animated, adjustable or just static. You can also use separate canvas tags for each Gauge, but this example uses just one larger canvas tag.
- How to use AJAX to update your charts
Make AJAX requests using RGraph. By using AJAX to update your charts you can reduce bandwidth used, create faster pages and have those pages use less bandwidth (only the new chart data is transferred from the server to your browser instead of the whole page).
- How to create a floating progress bar
Create a progress bar that doesn't begin at zero - a floating progress bar. This is done by using a multi-segment progress bar with the first segments color set as transparent.
- How to create a plus/minus chart and a Sparkline chart
Use RGraph to create small Sparkline style inline charts. This can be done quite easily using the line/bar chart properties and this page show you two examples of such charts that are embedded in large blocks of text.
- How to create a combined Bar and Vertical Progress chart
Combine a Bar chart and the Vertical Progress bar to create a Bar chart with Vertical Progress bars instead of regular bars. This is a novel use of the Bar chart and the Vertical Progress Bar and can be used when you have a set of data where each entry has its own "child value".
- How to make a transition effect
Create a transition between two charts occupying the same space. This transition uses one of the CSS based effects that come with RGraph.
- How to add events to your charts
Add events to your charts such as the
mousemoveevents. This HOWTO takes you through step-by-step adding the event listeners to the chart using the
- How to add images to your charts
Add images to your chart using a variety of methods. This HOWTO demonstrates (and provides you with example code) the various methods from tooltips to CSS positioning.
- How to add links to your charts.
Add links to your charts using a variety of methods. This HOWTO demonstrates (and provides you with example code) the various methods from tooltips, event listeners to a simple link around the canvas tag.
- How to use the ModalDialog with events
Use the bundled ModalDialog with RGraph events. The ModalDialog can be used to show something (eg photos) or as a way to get input from the user that's triggered by clicking on the chart.