QwtPlotLegendItem and QwtLegendItem

[jesse_mark]

What is the difference between QwtPlotLegendItem and QwtLegendItem ???

In the documents, I found QwtLegendItem but not QwtPlotLegendItem.
In my Qwt library, I found QwtPlotLegendItem but not QwtLegendItem.
I have
#include <qwt_plot_legenditem.h>
but not
#include <qwt_legenditem.h>


I'm trying to use
qwtLegenditem.setItemmode(..)

but i can not find it. I am using qwtPlotLegendItem

Thank you.

[Uwe]

QwtPlotLegendItem is a new plot item in SVN trunk that displays a legend on the plot canvas - in opposite to QwtLegend that is a widget aligned to the plot canvas. QwtLegendItem is a class you don't need to know as long as you don't want to modify what happens on a QwtLegend.

I guess you are looking for QwtLegend::setItemMode ( or QwtLegend::setDefaultItemMode with SVN trunk ).

Uwe

[jesse_mark]

Yes I am using QwtPoltLegendItem, because i want to display the legend on the plot canvas not aligned with the plot.

I'm trying to change the mode of the QwtPoltLegendItem , so i can click on it and display the curve related to each item on the legend.
so is there a way to change the item mode for QwtPoltLegendItem or not ??


Sorry, one more thing is how can i remove a curve from the legend even though still attached to the plot ?

[Uwe]

I'm trying to change the mode of the QwtPoltLegendItem , so i can click on it and display the curve related to each item on the legend. so is there a way to change the item mode for QwtPoltLegendItem or not ??

Plot items are no widgets - they can't have a focus and they don't get any mouse or key events.

You could implement an event filter for the canvas ( or with SVN trunk you can overload its mousePressEvent ) where you handle mouse clicks yourself. The geometries of the legend entries are available.

Another option is to use an external legend - what means a legend that is not known to the layout system of the plot. Then you can put it on top of the canvas manually using QWidget:.setGeometry(). With Qwt 6.0 you would have to insert the legend as QwtPlot::ExternalLegend, with SVN trunk you have to setup a signal/slot connection instead: see the legends example. But note that you will also have to implement some code to layout the legend, when you want to export/print the plot.

Sorry, one more thing is how can i remove a curve from the legend even though still attached to the plot ?

curve->setItemAttribute( QwtPlotItem::Legend, false );

curve->setItemAttribute( QwtPlotItem::Legend, false );

To copy to clipboard, switch view to plain text mode 

Uwe