Android 当片段显示在活动的布局中时，如何开始转换是最佳实践吗？

我有一个活动，其中只包含用于渲染内部片段的FrameLayout

StartActivity.java

public class StartActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_start);

    final ViewGroup group = (ViewGroup)findViewById(R.id.fragment_container);

    IntroFragment fragment = new IntroFragment();

    FragmentManager fm = getFragmentManager();

    FragmentTransaction ft = fm.beginTransaction();
    ft.add(R.id.fragment_container, fragment);

    ft.commit();}

activity_start.xml

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" android:id="@+id/fragment_container">

ChangeBounds转换的问题是，当片段被渲染时，OnGlobalYoutListener调用，TransitionManager将场景从scene1更改为scene2。除了ChangeBounds外，淡入淡出转换效果非常好。ChangeBounds根本不起作用，就像我没有这个代码一样

ChangeBounds bounds = new ChangeBounds();

set.addTransition(fadeIn);

为什么会发生

哦，对不起，下面两个场景

scene_one.xml

 <RelativeLayout
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">
        <ImageView
            android:visibility="invisible"
            android:layout_marginTop="40dp"
            android:id="@+id/circle_logo"
            android:layout_centerHorizontal="true"
            android:layout_centerVertical="true"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"  android:background="@drawable/circle_logo"/>
        <TextView
            android:visibility="invisible"
            android:id="@+id/title_logo"
            android:layout_marginTop="10dp"
            android:layout_centerHorizontal="true"
            android:layout_centerVertical="true"
            android:gravity="center"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textColor="@color/white"
            android:textSize="25dp"
            android:text="Booking" />
    </RelativeLayout>

scene_two.xml

<RelativeLayout
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:orientation="vertical"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">
        <ImageView
            android:id="@+id/circle_logo"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" android:background="@drawable/circle_logo" />
        <TextView
            android:id="@+id/title_logo"
            android:layout_marginTop="10dp"
            android:layout_centerHorizontal="true"
            android:layout_below="@+id/circle_logo"
            android:gravity="center"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textColor="@color/white"
            android:textSize="25dp"
            android:text="Booking" />
    </RelativeLayout>

这个代码帮助了我

public class StartActivity extends Activity {

@TargetApi(Build.VERSION_CODES.LOLLIPOP)
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_start);

    final ViewGroup group = (ViewGroup)findViewById(R.id.fragment_container);

    scheduleStartPostponedTransition(group);

    IntroFragment fragment = new IntroFragment();

    FragmentManager fm = getFragmentManager();

    FragmentTransaction ft = fm.beginTransaction();
    ft.add(R.id.fragment_container, fragment);

    ft.commit();

}

private void scheduleStartPostponedTransition(final View sharedElement) {
    sharedElement.getViewTreeObserver().addOnPreDrawListener(
            new ViewTreeObserver.OnPreDrawListener() {
                @Override
                public boolean onPreDraw() {
                    sharedElement.getViewTreeObserver().removeOnPreDrawListener(this);
                    startPostponedEnterTransition();
                    return true;
                }
            });
}

@TargetApi(Build.VERSION_CODES.KITKAT)
public void startPostponedEnterTransition(){
    ViewGroup root = (ViewGroup) findViewById(R.id.scene_root);

    final Scene scene2 = Scene.getSceneForLayout(root, R.layout.intro_scene_two, getApplicationContext());

    final TransitionSet set = new TransitionSet();
    set.setDuration(10000);
    set.setOrdering(TransitionSet.ORDERING_TOGETHER);
    set.addTarget(R.id.circle_logo);
    set.addTarget(R.id.title_logo);

    Fade fadeIn = new Fade(Fade.IN);

    ChangeBounds bounds = new ChangeBounds();

    set.addTransition(fadeIn);
    set.addTransition(bounds);

    TransitionManager.go(scene2, set);
}

我从本文中获得了想法和实现

public class StartActivity extends Activity {

@TargetApi(Build.VERSION_CODES.LOLLIPOP)
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_start);

    final ViewGroup group = (ViewGroup)findViewById(R.id.fragment_container);

    scheduleStartPostponedTransition(group);

    IntroFragment fragment = new IntroFragment();

    FragmentManager fm = getFragmentManager();

    FragmentTransaction ft = fm.beginTransaction();
    ft.add(R.id.fragment_container, fragment);

    ft.commit();

}

private void scheduleStartPostponedTransition(final View sharedElement) {
    sharedElement.getViewTreeObserver().addOnPreDrawListener(
            new ViewTreeObserver.OnPreDrawListener() {
                @Override
                public boolean onPreDraw() {
                    sharedElement.getViewTreeObserver().removeOnPreDrawListener(this);
                    startPostponedEnterTransition();
                    return true;
                }
            });
}

@TargetApi(Build.VERSION_CODES.KITKAT)
public void startPostponedEnterTransition(){
    ViewGroup root = (ViewGroup) findViewById(R.id.scene_root);

    final Scene scene2 = Scene.getSceneForLayout(root, R.layout.intro_scene_two, getApplicationContext());

    final TransitionSet set = new TransitionSet();
    set.setDuration(10000);
    set.setOrdering(TransitionSet.ORDERING_TOGETHER);
    set.addTarget(R.id.circle_logo);
    set.addTarget(R.id.title_logo);

    Fade fadeIn = new Fade(Fade.IN);

    ChangeBounds bounds = new ChangeBounds();

    set.addTransition(fadeIn);
    set.addTransition(bounds);

    TransitionManager.go(scene2, set);
}