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View Full Version : Dial Widgets, Using qwt, Widget Plugin Questions



adamflyer
20th May 2015, 19:42
Hi all,

I am in the process of learning Qt. I'm using Qt 5.4.1 on Ubuntu 12.04. As my first project I am trying to create a desktop data acquisition application streaming data from an arduino. I was able to follow a tutorial to get data from the arduino into the "LCD Number" widget, a good first step. Now I am trying to get my incoming streaming data from the arduino into some nice looking dial gauges and graphs.

I downloaded qwt-6.1.2 and after much learning and headache managed to get it to compile and show up in the Qt Creator/Designer widgets area. I dragged over the "QwtDial" into the main window and hit run and I get the dial but no needle. I think I am missing something very fundamental about how to work with Qt and qwt. I see there is an examples folder in the qwt folder and have looked through the qwt documentation and reached the end of google but I'm not connecting the dots, probably due to my lack of programming knowledge.

1. Is there a simple explanation of the workflow using Qt widgets and widget plugins? Is the intent to create a widget as plugin in a final state, load the plugin, and then just use the widget as is in your program; or start with a widget plugin and then modify and add to the way it works in the current program.

2. For the case of the qwt plugin widget "QwtDial" is there a way to get a needle to be displayed on the dial? Or does the "QwtDial" widget need to be configured with a needle before it is build into a plugin? An simple example of how to get a needle would be great to have.

Thanks for any help.

Adam

adamflyer
9th June 2015, 03:16
bump......