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Android Animations and Transitions The Transitions Framework Transitioning Back and Forth

michael lee
michael lee
5,179 Points
Posted by michael lee
michael lee
5,179 Points

Make sure you include both the forward set and the backward set!

this is challenge 2 of 4 and I think I've included both sets? but this error message pops up

MainActivity.java 
public class MainActivity extends Activity {

    protected TransitionManager mTransitionManager;
    protected Scene mScene1;
    protected Scene mScene2;
    protected Scene mCurrentScene;
    protected TransitionSet mForwardSet;
    protected TransitionSet mBackwardSet;

    // Some code omitted for brevity

    public void onButtonClicked(View view) {
        if (mCurrentScene == mScene2) {
            mCurrentScene = mScene1;
        }
        else {
            mCurrentScene = mScene2;
        }
        mTransitionManager.transitionTo(mCurrentScene);
    }

    protected void setupTransitions() {
        // These methods are setting up scenes and transitions sets like in the video
        initScenes();
        initSets(); 
      mTransitionManager = new TransitionManager();
        // Start here!

        TransitionSet mForwardSet = new TransitionSet();
      TransitionSet mBackwardSet = new TransitionSet();
      //Expanded Scene

        mTransitionManager.setTransition(mScene1, mScene2, mBackwardSet);
        mTransitionManager.setTransition(mScene2, mScene1, mForwardSet);
        mScene2.enter();

    }
}