MythTV can dies when you attempt to upgrade from a default install 0.21 to 0.22

[danielk]

MythTV can dies when you attempt to upgrade from a default install 0.21 to 0.22 if you don't install the extra themes. G.A.N.T was the default in the last release, but is now an extra theme.

The problem is that the Theme fallback code does not work if your theme exists but is incompatible with MythTV 0.22.

[sphery]

This will require backporting either [22542] (use gContext->SaveSetting?() to write the fallback theme, Terra, to the database--which will cause a clear cache) or [22544] (check settings overrides in MythDB::GetSetting?()) or explicitly calling MythDB::ClearSettingsCache?() from MythDB::OverrideSettingForSession?(). Once that's done, we always get a valid Theme; however, we still need to fix the "QPainter: Painter not active" errors which prevent drawing the theme properly (showing which button is selected) that occur when the theme is changed late in the initialization process.

[sphery]

(In [22586]) Fix theme reloading and resetting in mythfrontend with painting fixes found by Chris Pinkham. Refs #7382.

[sphery]

(In [22587]) Use a define for the DEFAULT_UI_THEME rather than scattering the literal theme name throughout the code. Refs #7382.

[sphery]

(In [22588]) Fix theme reloading and resetting in mythfrontend for -fixes. Refs #7382.

Backports [22544], [22586], and [22587] from trunk. Also backports all of [22542] except the change from OverrideSettingForSession?() to SaveSetting?() (which I'll be reverting from trunk, as it's no longer required).

[sphery]

(In [22591]) Add a capability for mythtv-setup to fall back to a default UI theme if the specified UI theme is invalid. This rearranges mythtv-setup's UI setup to be very similar to mythfrontend's. Refs #7382.

[sphery]

(In [22592]) Add a capability for mythtv-setup to fall back to a default UI theme if the specified UI theme is invalid. Backports [22591] from trunk. Fixes #7382.

[sphery]

(In [22593]) Allow fallback to MythCenter?-wide if Terra is missing. Previously, the fallback was only used if the default UI theme was and incompatible version. Refs #7382.

[sphery]

(In [22594]) Allow fallback to MythCenter?-wide if Terra is missing. Backports [22593] from trunk. Refs #7382.

[sphery]

(In [22771]) Refs #7382. Fix UI theme and OSD theme changes due to broken/missing themes to use overrides rather than changing the database value. Backports [22589] from trunk.