Function setMainLayoutVisibility

setMainLayoutVisibility(isVisible): void
JMap.UI.setMainLayoutVisibility

Set the main UI layout visibility.

By default main UI layout is visible.
Parameters
- isVisible: boolean
  false to hide, true to show
Returns void
Throws
if isVisible is not boolean value

Example
```
// display main layout
JMap.UI.setMainLayoutVisibility(true)

// hide main layout
JMap.UI.setMainLayoutVisibility(false)
```