panning charts while zoomed in

RichardWest · Post by **RichardWest** » Sat Feb 10, 2007 8:30 am

I have searched the forum and found many people asking about panning charts while zoomed. There are couple suggested answers, and even a couple proposed solutions. My question isn't exactly "How can I pan a chart while zoomed" more if JFreeChart has added support to make this possible/easier.

In my normal style, here are links to other threads discussing this exact topic:

Asking:
http://www.jfree.org/phpBB2/viewtopic.p ... ht=panning
http://www.jfree.org/phpBB2/viewtopic.p ... ht=panning
http://www.jfree.org/phpBB2/viewtopic.p ... ht=panning
http://www.jfree.org/phpBB2/viewtopic.p ... ht=panning

Asking and mention a solution from an old version of JFreeChart:
http://www.jfree.org/phpBB2/viewtopic.p ... ht=panning
http://www.jfree.org/phpBB2/viewtopic.p ... ht=panning

Asking and mention that there would be a possible solution added to JFreeChart:
http://www.jfree.org/phpBB2/viewtopic.p ... ht=panning

Asking and present a temporary solution:
http://www.jfree.org/phpBB2/viewtopic.php?t=644
http://www.jfree.org/phpBB2/viewtopic.php?t=6342

Post by **david.gilbert** » Mon Feb 12, 2007 6:11 pm

Henry Proudhon (who has been working on the experimental SWT support) is currently looking at adding panning support (I think both in the ChartPanel class for Swing, and the ChartComposite class for SWT). I'll let him know about this thread, and I'll try to take a look myself also (I'm short on time as always).

heprom · Post by **heprom** » Tue Feb 13, 2007 1:12 pm

Thanks for the review, it will help me to get started on this and hopefully provide a clever solution to add panning in JFreeChart.

aiello · Post by **aiello** » Fri Oct 05, 2007 3:51 pm

Any word on the state of this enhancement? My application would certainly benefit from panning.... I'll look into hacking a solution together if this is still pretty far off, but if we can expect experimental support in the not-too-distant future, I'll hold off and wait for it.

Thanks!

annac · Post by **annac** » Fri Oct 05, 2007 4:50 pm

I've also been looking for a solution.

I didn't want to get rid of the built-in zooming feature so I ended up subclassing the ChartPanel class and overriding the mousePressed and mouseDragged methods to check if the shift key was a modifier to the event. this way, if you hold down the shift key while moving the mouse you can pan (by changing the upper and lower bounds of the domain axis), and otherwise the methods pass the event to their super method and the mouse will initiate zooming. it seems to work quite well so far. I haven't tried to implement this with subplots yet.

annac · Post by **annac** » Fri Oct 05, 2007 4:52 pm

oh. and the mouseReleased method as well

annac · Post by **annac** » Fri Oct 05, 2007 6:14 pm

got panning to work with subplots

RichardWest · Post by **RichardWest** » Fri Oct 05, 2007 6:52 pm

annac wrote:got panning to work with subplots

Submit the code as a patch. You will receive a contributor credit and help others as well. The code will also help Henry and David work towards a generic solution.

gribas · Post by **gribas** » Wed Oct 31, 2007 8:48 pm

Hello,

I didn't quite get the "while zoomed" part. A pan is a pan, the zoom level should not come into play. If you'd like you can establish some min/max limits to the axis (I do that).
Anyway, I think this class will do what you're asking for:

http://www.jfree.org/phpBB2/viewtopic.php?p=59287#59287

HTH,
Gustavo