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Android Animations and Transitions The Transitions Framework Transitioning Back and Forth

Ramy Elsaraf
Ramy Elsaraf
7,633 Points

I get a nullpointerexception when I add finally mTransitionManager.transitionTo(mCurrentScene); sthing wrong withis l

something wrong with the above line

Seth Kroger
Seth Kroger
56,407 Points

Can you show us your code? I will help a lot in figuring out what's going on.

Jasmeet Singh
Jasmeet Singh
20,145 Points

Did you called the setUpTransitions method in onCreate of the activity?

2 Answers

I am having the same problem. Would love to know why.

here is my code:

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(); 

    // Start here!

  TransitionManager mTransitionManager = new TransitionManager();

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

}

}

Jasmeet Singh
Jasmeet Singh
20,145 Points

Don't create another mTransitionManger object it's already declared. Just use it.

Ramy Elsaraf
Ramy Elsaraf
7,633 Points

mTransitionManager is declared twice for me