在MapFragment中放置自動完成功能：在舊API上不可見

Question

經過相當多的努力之後，我設法在我的MapFragment中放置了自動填充功能。仍然有一個問題。

在我的Android模擬器（API 24），它是可見的，我可以用它：

在我的智能手機（API 19）我還看不出來，除了一小瞬間只在地圖加載之前。

我map_layout.xml是這樣的：

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout 
    xmlns:android="http://schemas.android.com/apk/res/android" 
    android:id="@+id/map_fragment_container" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:orientation="vertical" > 

    <android.support.v7.widget.CardView 
     xmlns:card_view="http://schemas.android.com/apk/res-auto" 
     android:id="@+id/card_view" 
     android:layout_gravity="top" 
     android:layout_margin="5dp" 
     android:layout_width="match_parent" 
     android:layout_height="40dp" 
     card_view:cardCornerRadius="4dp"> 
    </android.support.v7.widget.CardView> 

</RelativeLayout> 

的MapFragment.java裏面的代碼是這一個：

@Override 
public void onViewCreated(View view, Bundle savedInstanceState) { 
    super.onViewCreated(view, savedInstanceState); 

    // Initialise a new fragment inside of this one. 
    mFragmentManager = getChildFragmentManager(); 
    mSupportMapFragment = (SupportMapFragment) mFragmentManager.findFragmentByTag("mapFragment"); 
    mSupportPlaceAutocompleteFragment = (SupportPlaceAutocompleteFragment) mFragmentManager.findFragmentByTag("autocompleteFragment"); 

    // Never inflate fragments inside other fragments in a layout.xml! 
    // Do it programmatically. 
    // See here for reference: http://stackoverflow.com/a/19815266/4938112. 
    if (mSupportMapFragment == null) { 
     mSupportMapFragment = new SupportMapFragment(); 
     mFragmentTransaction = mFragmentManager.beginTransaction(); 
     mFragmentTransaction.add(R.id.map_fragment_container, mSupportMapFragment, "mapFragment"); 
     mFragmentTransaction.commit(); 
     mFragmentManager.executePendingTransactions(); 
    } 

    // Asynchronous thread to load map. 
    mSupportMapFragment.getMapAsync(this); 

    if (mSupportPlaceAutocompleteFragment == null) { 
     mSupportPlaceAutocompleteFragment = new SupportPlaceAutocompleteFragment(); 
     mFragmentTransaction = mFragmentManager.beginTransaction(); 
     mFragmentTransaction.add(R.id.card_view, mSupportPlaceAutocompleteFragment, "autocompleteFragment"); 
     mFragmentTransaction.commit(); 
     mFragmentManager.executePendingTransactions(); 
    } 

} 

我已經發現如果我只是將地址自動填充直接附加到map_fragment_container，即使在我的智能手機上，我也能看到它，但它有一個看不見的背景。

任何提示？

Answer 1

只要把兩個組件父FrameLayout內：

<FrameLayout 
    xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:card_view="http://schemas.android.com/apk/res-auto" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent"> 

    <FrameLayout 
     android:id="@+id/map_fragment_container" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent"/> 

    <android.support.v7.widget.CardView 
     android:id="@+id/card_view" 
     android:layout_gravity="top" 
     android:layout_margin="@dimen/margin_1" 
     android:layout_width="match_parent" 
     android:layout_height="@dimen/card_view_height" 
     card_view:cardCornerRadius="@dimen/card_corner_radius"/> 

</FrameLayout>