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Android Animations and Transitions The Transitions Framework Transitioning Back and Forth

Ramy Elsaraf
Ramy Elsaraf
7,633 Points
Posted by 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
56,414 Points
Seth Kroger
Seth Kroger
56,414 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
Jasmeet Singh
Jasmeet Singh
20,145 Points

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

2 Answers

Christina Campbell
Christina Campbell
12,098 Points
Christina Campbell
Christina Campbell
12,098 Points

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
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
Ramy Elsaraf
Ramy Elsaraf
7,633 Points

mTransitionManager is declared twice for me