Add new imagepanel, but it doesn't display correctly. #1605

[jeffryHo]

Description

#1605

Fix add a new image panel but it's image didn't display correctly problem.

Checklist

• If you are addressing rendering issues, please provide:
  • Images of both, broken and fixed renderings.
  • Source code to reproduce the issue, e.g. a YAML or rosbag file with a MarkerArray msg.
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[rhaschke]

Thanks for your contribution! Next time, please use a more informative main description for the PR.

[jeffryHo]

Thanks for merged my PR, I found that you changed the setting of floating, but when floating is set to true, the panel cannot be displayed because you did not add the panel to the main window. Have you ever tested it?

if floating is true then rviz show like this

When the PanelDockwidget is created, its parent class is not specified.

I don't understand what you mean "floating" mutually excludes "docked"? After addDockWidget you can also make the widow floating.

[rhaschke]

I'm sorry. I didn't explicitly test floating=true. I was assuming that a floating DockWidget shouldn't require a prior call to addDockWidget(), because it will not be docked. I pushed a fixup commit.