Maintenance issues from SliceViewer changes

[Owen Arnold]

1) SliceViewer.cpp is already too long. The code that applies icon switching should be refactored out into functions. Reading the function calls should make the behaviour a lot more readable than it currently is.

This is what it currently looks like in one place:

if (m_peaksPresenter->size()>0)  {
    icon.addFile(QString::fromStdString(g_iconPeakListOn),
                   QSize(), QIcon::Normal, QIcon::On);
    ui.btnPeakOverlay->setIcon(icon);
    ui.btnPeakOverlay->setChecked(true);
  }  else {

    icon.addFile(QString::fromStdString(g_iconPeakList),
                   QSize(), QIcon::Normal, QIcon::Off);
    ui.btnPeakOverlay->setIcon(icon);
    ui.btnPeakOverlay->setChecked(false);
  }

What it should look like is something of the form:

if (m_peaksPresenter->size()>0)  {
    selectPeakOverlayButton();
  }  else {
    unselectPeakOverlayButton();
  }

2) You have introduced a hard-coded magic number into SelectWorkspacesDialog.h. In the SliceViewer your are NOT using a QDialog in a polymorphic way. Therefore you can introduce new methods onto SelectWorkspacesDialog to indicate that a custom button is being used.

• Remove static const int CustomButton = 45654
• Add a const method to SelectWorkspaceDialog to indicate the state that you want instead. This should make ​https://github.com/mantidproject/mantid/blob/master/Code/Mantid/MantidQt/SliceViewer/src/SliceViewer.cpp#L2217:L219 a lot more readable.

[Nick Draper]

Moved to R3.5 at the R3.4 code freeze

[Stuart Campbell]

This ticket has been transferred to github issue ​12324