Android Tutorial Android Charts Framework

The purpose of this framework is to allow you to easily add different types of charts to your projects.
The current version supports pie charts, line charts and bar charts.

The framework is implemented as code modules. You are free to customize the code as needed.

I also recommend you to go over the code. It demonstrates several concepts including: usage of custom types, drawings, string measurements and region clipping.

The code module is attached as part of the example project.
Questions, comments and suggestions are welcomed.

Klaus has posted a version that includes automatic scaling: http://www.b4x.com/android/forum/threads/android-charts-framework.8260/page-7#post-240181

 

[Erel]

First post was updated with a new version. This version adds support for line charts.
A line chart can show a single line or multiple lines.
Some notes about the line chart:
- The X axis values are treated as strings.
- The Y axis values are treated as numbers.
- The data is added by adding the next X point. For this point you need to supply the Y value in case of a single line, or an array of Y values in case of multiple lines.

The code in the first post demonstrates both a single line and multiple lines charts.

All the drawing code is included in the Charts module. You are free to customize it as needed.

 

[FrankR]

This is an amazingly powerful addition. Thank you.

 

[tester198]

Absolut powerful framework thank you Erel you are the best.

 

[Erel]

Thank you guys. Bars chart will also be added soon.

 

[Erel]

Support for bar charts, including stacked bar charts was added. The updated code is attached to the first post. There were other fixes related to graph drawing as well.

 

[vksptg]

i am unable to download code..

 

[Erel]

Have you purchased Basic4android? If yes please contact [email protected] and your account will be set.

 

[DEHiCKA]

Does it support dynamic data and multi-touch zooming and scrolling like androidplot JAVA API?

 

[Erel]

What do you mean with dynamic data?

Zooming and scrolling are not implemented in this module. It shouldn't be difficult to add scrolling yourself. Zooming is more difficult but is also possible.

 

[tresor]

Vertical lines

Hello, I´m trying to draw a vertical line in a multiline chart, like changes between 0 and 1 in binary code or like a rectangle with vertical lines. When I use the multiline chart facilities of B4A and I plot a new point, the x-axis value is incremented 1 step so I never get a vertical line but a slope. Does anyone know how to draw a vertical line in a multiline chart? Thank you in advance.

 

[Erel]

You will need to modify the code in order to draw vertical lines. It shouldn't be too difficult. Post here is you encounter any problem and I'll help you.

 

[tresor]

Thanks. I´ve got it. At the end of "Sub Create2LinesTab" I appended a sentence LD.Canvas.DrawLine() and it works. Also I put a sentence LD.Canvas.DrawCircle() and it works also.

 

[Nyptop]

I get the error 'Error description: Unknown type: graph Are you missing a library reference?'. Any suggestions?

Thanks

 

[Erel]

Graph type is defined in the Charts code module. Have you added it to your project?

 

[Nyptop]

Thanks Erel,

One question still though: How is the layout laid out? I'm having problems knowing what to do with panels.

Thanks Again,

Neil

 

[Erel]

Each graph is drawn on a Panel. You can add this panel with the designer or by code and put it wherever needed.

 

[Nyptop]

Still having problems: The program is not recognising the keyword 'chart'. If you wish to have a look i have attached the file.

 

[klaus]

As Erel already told you, you need to add the Chart module.
You need to download the Charts.zip file in the first post.
Then add the the Charts.bas file into your project with Project/Add Existing Module.

Best regards.

 

[Nyptop]

Sorry, I have added chart module etc. Just uploaded the wrong one. Here is the correct one.