Start motion scene programmatically

Question

I have a motion layout with this layoutDescription: app:layoutDescription=\"@xml/scene\"

scene.xml

Answer 1

If anyone's doing this from a fragment:

1. Import:

   import androidx.constraintlayout.motion.widget.MotionLayout;
   

2. Instantiate MotionLayout:

   MotionLayout motionLayout = view.findViewById(R.id.your_motion_layout);
   

3. Transition to the end/start of motion:

   motionLayout.transitionToStart();
   

or

    motionLayout.transitionToEnd();

Answer 2

We can simply do like this motion_layout.transitionToEnd()

But on Activity resumed, It'll start our animation so fast that we may miss the few or the whole animation. so I would suggest to add some delay like.

GlobalScope.launch (Dispatchers.IO){
        delay(1000)
        withContext(Dispatchers.Main){
            motion_layout.transitionToEnd()
        }
    }

Also you'll need to add Coroutines dependency if not added.

implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.9'

Answer 3

Finally Im doing this:

((MotionLayout)findViewById(R.id.motionLayout)).transitionToEnd();
((MotionLayout)findViewById(R.id.motionLayout)).transitionToStart();

Answer 4

In Latest Update of Constraint **2.0.0-beta1** Layout There are Public methods add in motion layout 
        you can get these methods with the help of motionlayout id 
    **motionLayout** 

     1. public void setProgress (float pos) 
     2. public void setTransition (int
           beginId,int endId)  
     3. public void setTransitionDuration (int
               milliseconds)  public void setTransitionListener
               (MotionLayout.TransitionListener listener)

     4. public void setState (int
               id,int screenWidth, 
                             int screenHeight)

     5. if(wantShowUi)
            {
                newUserActivityBinding.coordinatorLayout.transitionToStart();
            }
            else
            {
                newUserActivityBinding.coordinatorLayout.transitionToEnd();
            }

      <android.support.constraint.motion.MotionLayout
                xmlns:android="http://schemas.android.com/apk/res/android"
                xmlns:app="http://schemas.android.com/apk/res-auto"
                xmlns:tools="http://schemas.android.com/tools"
                android:id="@+id/motionLayout"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                app:layoutDescription="@xml/motion_scene_01"
                tools:showPaths="true">

            <View
                    android:id="@+id/button"
                    android:background="@color/colorAccent"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:soundEffectsEnabled="false"
                    tools:layout_editor_absoluteY="361dp"
                    tools:layout_editor_absoluteX="61dp"/>


        </android.support.constraint.motion.MotionLayout>

Answer 5

You can also do this in your xml with

motion:autoTransition="animateToEnd"

and

motion:autoTransition="animateToStart"