Make QStateMachine inherit QState

This removes the need for a "root state" in the machine; or rather,
the machine _is_ the root state.
User code can now pass in a QStateMachine directly to the QState
constructor, instead of machine->rootState().
This also means we could get rid of the "proxying" from the machine
to the root state for things like properties (initialState et al),
finished() signal and auto-reparenting of states (the ChildAdded
event hack).
A fun little side-effect of this change is that it's now possible
to embed state machines within state machines. We can't think of
a good use case yet where you would rather embed a stand-alone
state machine (with its own event processing etc.) rather than
having just a regular nested state, but it's neat and it works.

Reviewed-by: Eskil Abrahamsen Blomfeldt

1 files changed, 4 insertions, 4 deletions

diff --git a/examples/animation/sub-attaq/graphicsscene.cpp b/examples/animation/sub-attaq/graphicsscene.cpp
index bd37ce2..fcbc1b3 100644
--- a/examples/animation/sub-attaq/graphicsscene.cpp
+++ b/examples/animation/sub-attaq/graphicsscene.cpp
@@ -230,17 +230,17 @@ void GraphicsScene::setupScene(const QList<QAction *> &actions)
     QStateMachine *machine = new QStateMachine(this);
 
     //This state is when the player is playing
-    PlayState *gameState = new PlayState(this,machine->rootState());
+    PlayState *gameState = new PlayState(this,machine);
 
     //Final state
-    QFinalState *final = new QFinalState(machine->rootState());
+    QFinalState *final = new QFinalState(machine);
 
     //Animation when the player enter in the game
-    QAnimationState *lettersMovingState = new QAnimationState(machine->rootState());
+    QAnimationState *lettersMovingState = new QAnimationState(machine);
     lettersMovingState->setAnimation(lettersGroupMoving);
 
     //Animation when the welcome screen disappear
-    QAnimationState *lettersFadingState = new QAnimationState(machine->rootState());
+    QAnimationState *lettersFadingState = new QAnimationState(machine);
     lettersFadingState->setAnimation(lettersGroupFading);
 
     //if new game then we fade out the welcome screen and start playing