如何设置 ListFragment 的 ListView 的样式

Question

我想保留这些方法：

setListShown(true);
setListShownNoAnimation(true);

但如果我使用

onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState)

用自定义样式的布局膨胀Fragment，不能使用之前的方法，并显示此异常：

07-30 20:17:46.937: E/AndroidRuntime(1374): Caused by: java.lang.IllegalStateException: Can't be used with a custom content view
07-30 20:17:46.937: E/AndroidRuntime(1374):     at android.support.v4.app.ListFragment.setListShown(ListFragment.java:282)
07-30 20:17:46.937: E/AndroidRuntime(1374):     at android.support.v4.app.ListFragment.setListShown(ListFragment.java:258)

那么，有什么可能的解决方案呢？

编辑：

Fragment 使用加载器从数据库中填充其ListView。所以这就是我想保留这些方法的原因，这里需要它们：

public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
        mAdapter.swapCursor(data);  
        if (isResumed()) {
            setListShown(true);
        } else {
            setListShownNoAnimation(true);
        }
    }

最简单的解决方案是根据ListFragment 源编写我自己的代码，并将进度小部件添加到布局中以显示相同的效果。到目前为止，我将按照我被告知的那样删除这些行。如果我做修改，我会在这里粘贴。

Answer 1

只需将原来的ListView 替换为onCreateView() 中的CustomListView 布局即可。为我工作。

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    View layout = super.onCreateView(inflater, container,
            savedInstanceState);
    ListView lv = (ListView) layout.findViewById(android.R.id.list);
    ViewGroup parent = (ViewGroup) lv.getParent();

    // Remove ListView and add CustomView  in its place
    int lvIndex = parent.indexOfChild(lv);
    parent.removeViewAt(lvIndex);
    LinearLayout mLinearLayout = (LinearLayout) inflater.inflate(
            R.layout.custom_list, container, false);
    parent.addView(mLinearLayout, lvIndex, lv.getLayoutParams());
    return layout;
}

Answer 2

我已经尝试过这个解决方案并且它有效：

在support ListFragment源代码中说，

如果您使用自己的自定义内容覆盖此方法， 考虑在您的布局中包含标准布局 android.R.layout 文件，以便您继续保留所有的标准行为 列表片段。特别是，这是目前唯一的方法 显示内置的不确定进度状态。

所以，我采用了 list_content.xml 并将我自己的风格应用到列表中：

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        style="@style/page_background">

    <LinearLayout android:id="@+id/progressContainer"
            android:orientation="vertical"
            android:layout_width="match_parent" 
            android:layout_height="match_parent"
            android:visibility="gone"
            android:gravity="center">

        <ProgressBar style="?android:attr/progressBarStyleLarge"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content" />
        <TextView android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:textAppearance="?android:attr/textAppearanceSmall"
                android:paddingTop="4dip"
                android:singleLine="true" />

    </LinearLayout>

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

        <ListView android:id="@android:id/list"
                android:layout_width="match_parent" 
                android:layout_height="match_parent"
                android:drawSelectorOnTop="false" 
                style="@style/rc_listview"/>
        <TextView android:id="@android:id/empty"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:gravity="center"
                android:textAppearance="?android:attr/textAppearanceLarge" />
    </FrameLayout>

</FrameLayout>

然后从支持源代码复制了一个固定的ListFragment。

• 我重命名了一些 ID 以匹配 XML 文件中的 ID。

• 删除其onCreateView()。

  public class FixedListFragment extends Fragment {
  
      final private Handler mHandler = new Handler();
  
      final private Runnable mRequestFocus = new Runnable() {
          public void run() {
              mList.focusableViewAvailable(mList);
          }
      };
  
      final private AdapterView.OnItemClickListener mOnClickListener
              = new AdapterView.OnItemClickListener() {
          public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
              onListItemClick((ListView)parent, v, position, id);
          }
      };
  
      ListAdapter mAdapter;
      ListView mList;
      View mEmptyView;
      TextView mStandardEmptyView;
      View mProgressContainer;
      View mListContainer;
      CharSequence mEmptyText;
      boolean mListShown;
  
      public FixedListFragment() {
      }
  
      /**
       * Provide default implementation to return a simple list view.  Subclasses
       * can override to replace with their own layout.  If doing so, the
       * returned view hierarchy <em>must</em> have a ListView whose id
       * is {@link android.R.id#list android.R.id.list} and can optionally
       * have a sibling view id {@link android.R.id#empty android.R.id.empty}
       * that is to be shown when the list is empty.
       * 
       * <p>If you are overriding this method with your own custom content,
       * consider including the standard layout {@link android.R.layout#list_content}
       * in your layout file, so that you continue to retain all of the standard
       * behavior of ListFragment.  In particular, this is currently the only
       * way to have the built-in indeterminant progress state be shown.
       */
  
      /**
       * Attach to list view once the view hierarchy has been created.
       */
      @Override
      public void onViewCreated(View view, Bundle savedInstanceState) {
          super.onViewCreated(view, savedInstanceState);
          ensureList();
      }
  
      /**
       * Detach from list view.
       */
      public void onDestroyView() {
          mHandler.removeCallbacks(mRequestFocus);
          mList = null;
          mListShown = false;
          mEmptyView = mProgressContainer = mListContainer = null;
          mStandardEmptyView = null;
          super.onDestroyView();
      }
  
      /**
       * This method will be called when an item in the list is selected.
       * Subclasses should override. Subclasses can call
       * getListView().getItemAtPosition(position) if they need to access the
       * data associated with the selected item.
       *
       * @param l The ListView where the click happened
       * @param v The view that was clicked within the ListView
       * @param position The position of the view in the list
       * @param id The row id of the item that was clicked
       */
      public void onListItemClick(ListView l, View v, int position, long id) {
      }
  
      /**
       * Provide the cursor for the list view.
       */
      public void setListAdapter(ListAdapter adapter) {
          boolean hadAdapter = mAdapter != null;
          mAdapter = adapter;
          if (mList != null) {
              mList.setAdapter(adapter);
              if (!mListShown && !hadAdapter) {
                  // The list was hidden, and previously didn't have an
                  // adapter.  It is now time to show it.
                  setListShown(true, getView().getWindowToken() != null);
              }
          }
      }
  
      /**
       * Set the currently selected list item to the specified
       * position with the adapter's data
       *
       * @param position
       */
      public void setSelection(int position) {
          ensureList();
          mList.setSelection(position);
      }
  
      /**
       * Get the position of the currently selected list item.
       */
      public int getSelectedItemPosition() {
          ensureList();
          return mList.getSelectedItemPosition();
      }
  
      /**
       * Get the cursor row ID of the currently selected list item.
       */
      public long getSelectedItemId() {
          ensureList();
          return mList.getSelectedItemId();
      }
  
      /**
       * Get the activity's list view widget.
       */
      public ListView getListView() {
          ensureList();
          return mList;
      }
  
      /**
       * The default content for a ListFragment has a TextView that can
       * be shown when the list is empty.  If you would like to have it
       * shown, call this method to supply the text it should use.
       */
      public void setEmptyText(CharSequence text) {
          ensureList();
          if (mStandardEmptyView == null) {
              throw new IllegalStateException("Can't be used with a custom content view");
          }
          mStandardEmptyView.setText(text);
          if (mEmptyText == null) {
              mList.setEmptyView(mStandardEmptyView);
          }
          mEmptyText = text;
      }
  
      /**
       * Control whether the list is being displayed.  You can make it not
       * displayed if you are waiting for the initial data to show in it.  During
       * this time an indeterminant progress indicator will be shown instead.
       * 
       * <p>Applications do not normally need to use this themselves.  The default
       * behavior of ListFragment is to start with the list not being shown, only
       * showing it once an adapter is given with {@link #setListAdapter(ListAdapter)}.
       * If the list at that point had not been shown, when it does get shown
       * it will be do without the user ever seeing the hidden state.
       * 
       * @param shown If true, the list view is shown; if false, the progress
       * indicator.  The initial value is true.
       */
      public void setListShown(boolean shown) {
          setListShown(shown, true);
      }
  
      /**
       * Like {@link #setListShown(boolean)}, but no animation is used when
       * transitioning from the previous state.
       */
      public void setListShownNoAnimation(boolean shown) {
          setListShown(shown, false);
      }
  
      /**
       * Control whether the list is being displayed.  You can make it not
       * displayed if you are waiting for the initial data to show in it.  During
       * this time an indeterminant progress indicator will be shown instead.
       * 
       * @param shown If true, the list view is shown; if false, the progress
       * indicator.  The initial value is true.
       * @param animate If true, an animation will be used to transition to the
       * new state.
       */
      private void setListShown(boolean shown, boolean animate) {
          ensureList();
          if (mProgressContainer == null) {
              throw new IllegalStateException("Can't be used with a custom content view");
          }
          if (mListShown == shown) {
              return;
          }
          mListShown = shown;
          if (shown) {
              if (animate) {
                  mProgressContainer.startAnimation(AnimationUtils.loadAnimation(
                          getActivity(), android.R.anim.fade_out));
                  mListContainer.startAnimation(AnimationUtils.loadAnimation(
                          getActivity(), android.R.anim.fade_in));
              } else {
                  mProgressContainer.clearAnimation();
                  mListContainer.clearAnimation();
              }
              mProgressContainer.setVisibility(View.GONE);
              mListContainer.setVisibility(View.VISIBLE);
          } else {
              if (animate) {
                  mProgressContainer.startAnimation(AnimationUtils.loadAnimation(
                          getActivity(), android.R.anim.fade_in));
                  mListContainer.startAnimation(AnimationUtils.loadAnimation(
                          getActivity(), android.R.anim.fade_out));
              } else {
                  mProgressContainer.clearAnimation();
                  mListContainer.clearAnimation();
              }
              mProgressContainer.setVisibility(View.VISIBLE);
              mListContainer.setVisibility(View.GONE);
          }
      }
  
      /**
       * Get the ListAdapter associated with this activity's ListView.
       */
      public ListAdapter getListAdapter() {
          return mAdapter;
      }
  
      private void ensureList() {
          if (mList != null) {
              return;
          }
          View root = getView();
          if (root == null) {
              throw new IllegalStateException("Content view not yet created");
          }
          if (root instanceof ListView) {
              mList = (ListView)root;
          } else {
              mStandardEmptyView = (TextView)root.findViewById(android.R.id.empty);
              if (mStandardEmptyView == null) {
                  mEmptyView = root.findViewById(android.R.id.empty);
              } else {
                  mStandardEmptyView.setVisibility(View.GONE);
              }
              mProgressContainer = root.findViewById(R.id.progressContainer);
              mListContainer = root.findViewById(R.id.listContainer);
              View rawListView = root.findViewById(android.R.id.list);
              if (!(rawListView instanceof ListView)) {
                  if (rawListView == null) {
                      throw new RuntimeException(
                              "Your content must have a ListView whose id attribute is " +
                              "'android.R.id.list'");
                  }
                  throw new RuntimeException(
                          "Content has view with id attribute 'android.R.id.list' "
                          + "that is not a ListView class");
              }
              mList = (ListView)rawListView;
              if (mEmptyView != null) {
                  mList.setEmptyView(mEmptyView);
              } else if (mEmptyText != null) {
                  mStandardEmptyView.setText(mEmptyText);
                  mList.setEmptyView(mStandardEmptyView);
              }
          }
          mListShown = true;
          mList.setOnItemClickListener(mOnClickListener);
          if (mAdapter != null) {
              ListAdapter adapter = mAdapter;
              mAdapter = null;
              setListAdapter(adapter);
          } else {
              // We are starting without an adapter, so assume we won't
              // have our data right away and start with the progress indicator.
              if (mProgressContainer != null) {
                  setListShown(false, false);
              }
          }
          mHandler.post(mRequestFocus);
      }   
  }
  

在那之后，一切都很完美。 只需在创建 Fragment 时扩充此 list_content.xml。

public View onCreateView (LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.list_content, container, false);
    return view;
}

Answer 3

另一个对我也有用的解决方案就是把这条线

<include layout="@android:layout/list_content" />

而不是您的 ListView。

您可以在其之上构建您自己的内容，或者用其他一些视图将其包围。例如，我的布局如下所示：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent" >

<RelativeLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="@dimen/default_view_padding"
        android:gravity="center"
        android:weightSum="4">

    <ImageButton
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:id="@+id/btnCounterBack"
            android:src="?attr/ic_previous"
            android:background="?android:attr/selectableItemBackground"
            android:contentDescription="@null"/>

    <TextView
            android:id="@+id/tvCounterLevel"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textAppearance="?android:attr/textAppearanceMedium"
            android:text="@string/counter_categories"
            android:layout_gravity="center"
            android:paddingTop="@dimen/default_view_padding"
            android:paddingBottom="@dimen/default_view_padding"
            android:layout_alignParentTop="true"
            android:layout_alignParentLeft="true"
            android:layout_alignParentStart="true"
            android:gravity="center"/>

</RelativeLayout>

<LinearLayout
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:gravity="center_vertical"
        android:background="?attr/dropShadowBackground"
        android:orientation="vertical" >

    <include layout="@android:layout/list_content" />

</LinearLayout>

Answer 4

setListShown(true); 和 setListShownNoAnimation(true); 不受支持包支持，仅在 Api Level 11+ 中可用。您要么必须放弃对

如果我对documentation 的理解正确，则无论如何都不必设置它们，因为true 是默认值