我正在尝试RecyclerView使用 aStaggeredGridLayout并通过让它测量视图并动态设置高度来使其成为固定高度。我正在覆盖onMeasure()，但它似乎并不总是正确测量。我会说它大约有50％的时间有效。另外 50% 的时间它在测量它。我认为这与文本何时换行有关view_tile_small.xml，但我不确定。
分段
public class AtTheMuseumFragment extends Fragment implements SwipeRefreshLayout.OnRefreshListener{
//Odds n Ends Variables
private MapFragment mapFragment;
private FragmentTransaction fragmentTransaction;
private User user = new User();
private MuseumCollection museumCollection;
private Context context;
//Story Grid Adapter Variables
private AtTheMuseumAdapter nearMeAdapter;
private TileFactory tileFactory;
//Interfaces
private OnFragmentChangeListener changeListener;
@Bind(R.id.stories_list_view) RecyclerView storiesListView;
@Bind(R.id.swipe_container) SwipeRefreshLayout swipeRefreshLayout;
public static AtTheMuseumFragment newInstance(MuseumCollection museumCollection) {
AtTheMuseumFragment fragment = new AtTheMuseumFragment();
Bundle args = new Bundle();
fragment.setArguments(args);
return fragment;
}
public AtTheMuseumFragment() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
museumCollection = ((MainActivity) getActivity()).getMuseumCollection();
context = getActivity().getApplicationContext();
tileFactory = new TileFactory();
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_museum, container, false);
ButterKnife.bind(this, view);
//Sets up the layoutManager to the Mason View
storiesListView.setLayoutManager(new MeasuredStaggeredGridLayoutManager(2, StaggeredGridLayoutManager.VERTICAL));
//Sets up The map
try{
fragmentTransaction = getChildFragmentManager().beginTransaction();
mapFragment = MapFragment.newInstance(MapFragment.MUSEUM);
fragmentTransaction.add(R.id.museum_map, mapFragment).commit();
}catch (Exception e){
Log.d("Map - Initial Inflate:", e.getMessage());
}
//Sets up the swipe to refresh jawn
swipeRefreshLayout.setOnRefreshListener(this);
setNearMeAdapter();
return view;
}
@Override
public void onResume(){
super.onResume();
}
@Override
public void onAttach(Activity activity) {
super.onAttach(activity);
try {
changeListener = (OnFragmentChangeListener) activity;
} catch (ClassCastException e) {
throw new ClassCastException(activity.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onDetach() {
super.onDetach();
changeListener = null;
}
/**
* Loads the adapter once the data is ready
*
*/
public void setNearMeAdapter(){
List<MuseumObject> newList = museumCollection.getObjectsNearUser(User.position, 4);
List<Tile> tiles = tileFactory.createAtMuseumFeed(newList, true);
nearMeAdapter = new AtTheMuseumAdapter(context, tiles, getActivity());
storiesListView.setAdapter(nearMeAdapter);
}
/**
* Refreshes Adapter with new data
*
*/
public void refreshNearMeAdapter(){
//TODO CHANGE THIS TO LOCATION BASED WHEN TIME IS RIGHT - Peter
//nearMeAdapter.setNewData(MuseumCollection.getObjectsNearUser(User.position, 4));
List<MuseumObject> newList = museumCollection.getRandomOrder();
nearMeAdapter.setNewData(tileFactory.createAtMuseumFeed(newList,false));
}
/**
* Adds past data to the Adapter
*
*/
public void loadPastObjects(){
//TODO MAKE THIS NOT ONLY LOAD RANDOM DATA - Peter
List<MuseumObject> newList = museumCollection.getRandomOrder();
nearMeAdapter.addNewData(tileFactory.createAtMuseumFeed(newList, false));
nearMeAdapter.notifyDataSetChanged();
}
@Override
public void onRefresh() {
user.updateUserLocation();
refreshNearMeAdapter();
mapFragment.refreshMap(museumCollection.getObjectFeed());
swipeRefreshLayout.setRefreshing(false);
}
public interface OnFragmentChangeListener {
void onFragmentChange(String fragment);
}
@OnClick(R.id.explore_map)
public void exploreMap(){
changeListener.onFragmentChange("map");
}
@OnClick(R.id.load_more)
public void loadMore(){
loadPastObjects();
}
}
MeasuredStaggeredGridLayoutManager
public class MeasuredStaggeredGridLayoutManager extends StaggeredGridLayoutManager {
public MeasuredStaggeredGridLayoutManager(int spanCount, int orientation) {
super(spanCount, orientation);
}
private int[] mMeasuredDimension = new int[2];
@Override
public void onMeasure(RecyclerView.Recycler recycler, RecyclerView.State state,
int widthSpec, int heightSpec) {
final int widthMode = View.MeasureSpec.getMode(widthSpec);
final int heightMode = View.MeasureSpec.getMode(heightSpec);
final int widthSize = View.MeasureSpec.getSize(widthSpec);
final int heightSize = View.MeasureSpec.getSize(heightSpec);
int width = 0;
int height = 0;
int heightR = 0;
int heightL = 0;
for (int i = 0; i < getItemCount(); i++) {
measureScrapChild(recycler, i,
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(i, View.MeasureSpec.UNSPECIFIED),
mMeasuredDimension);
if (getOrientation() == HORIZONTAL) {
width = width + mMeasuredDimension[0];
if (i == 0) {
height = mMeasuredDimension[1];
}
} else {
if(i % 2 == 0){
heightL += mMeasuredDimension[1];
}else{
heightR += mMeasuredDimension[1];
}
if (i == 0) {
width = mMeasuredDimension[0];
}
}
}
switch (widthMode) {
case View.MeasureSpec.EXACTLY:
width = widthSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}
switch (heightMode) {
case View.MeasureSpec.EXACTLY:
height = heightSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}
if(heightL != 0 || heightR != 0){
height = (heightL > heightR) ? heightL : heightR;
}
//TODO come up with a better way to fix the slightly wrong height
// must be not accounting for padding or margin or something - Peter
height += (20 * (getItemCount() / 2)) + 5;
setMeasuredDimension(width, height);
}
private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec,
int heightSpec, int[] measuredDimension) {
View view = recycler.getViewForPosition(position);
if (view != null) {
RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) view.getLayoutParams();
int childWidthSpec = ViewGroup.getChildMeasureSpec(widthSpec,
getPaddingLeft() + getPaddingRight(), p.width);
int childHeightSpec = ViewGroup.getChildMeasureSpec(heightSpec,
getPaddingTop() + getPaddingBottom(), p.height);
view.measure(childWidthSpec, childHeightSpec);
measuredDimension[0] = view.getMeasuredWidth() + p.leftMargin + p.rightMargin;
measuredDimension[1] = view.getMeasuredHeight() + p.bottomMargin + p.topMargin;
recycler.recycleView(view);
}
}
}
在博物馆适配器
public class AtTheMuseumAdapter extends RecyclerView.Adapter<AtTheMuseumAdapter.MuseumStoriesViewHolder> {
private List<Tile> tiles;
private LayoutInflater inflater;
private AdapterCallback mListener;
private Context context;
public AtTheMuseumAdapter(Context context, List<Tile> tiles, Activity activity) {
this.tiles = tiles;
this.context = context;
inflater = LayoutInflater.from(this.context);
//Sets up interface between Stock Adapter and Fragment
try {
this.mListener = ((AdapterCallback) activity);
} catch (ClassCastException e) {
throw new ClassCastException("Fragment must implement AdapterCallback.");
}
}
@Override
public MuseumStoriesViewHolder onCreateViewHolder(ViewGroup viewGroup, int viewType) {
View view = inflater.inflate(R.layout.view_tile_small, viewGroup, false);
MuseumStoriesViewHolder holder = new MuseumStoriesViewHolder(view);
return holder;
}
@Override
public void onBindViewHolder(MuseumStoriesViewHolder holder, int position) {
Tile currentTile = tiles.get(position);
holder.title.setText(currentTile.getTitle());
holder.desc.setText(currentTile.getDescription());
holder.type.setText(currentTile.getObjectTypeName());
//Using Picasso since it handles caching and all that jazz
Picasso.with(context)
.load(currentTile.getImg())
.into(holder.img);
}
@Override
public int getItemCount() {
return tiles.size();
}
public void setNewData(List<Tile> newItems){
tiles = newItems;
notifyDataSetChanged();
}
public void addNewData(final List<Tile> newItems){
tiles.addAll(newItems);
notifyDataSetChanged();
}
class MuseumStoriesViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
public TextView type,title,desc;
public ImageView img;
public MuseumStoriesViewHolder(View itemView) {
super(itemView);
//Tried Butterknife, but it doesn't seem like it was working in the view holder. - Peter
type = (TextView) itemView.findViewById(R.id.small_box_type);
title = (TextView) itemView.findViewById(R.id.small_box_title);
desc = (TextView) itemView.findViewById(R.id.small_box_desc);
img = (ImageView) itemView.findViewById(R.id.small_box_image);
itemView.setOnClickListener(this);
}
@Override
public void onClick(View view) {
Tile t = tiles.get(getPosition());
switch (t.getObjectTypeName()){
case Tile.OBJECT_NAME:
mListener.onObjectClick(t.getObjectID());
break;
case Tile.TOUR_NAME:
mListener.onTourCLick(t.getTourID());
break;
case Tile.STORY_NAME:
mListener.onStoryClick(t.getObjectID(), t.getStoryID());
break;
}
}
}
public interface AdapterCallback {
public void onObjectClick(String objectID);
public void onStoryClick(String objectID, String storyID);
public void onTourCLick(String tourID);
}
}
view_tile_small.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="@dimen/margin_small"
android:background="@color/small_box_background_color">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<!--TODO Make layout_height wrap contenet -->
<ImageView
android:id="@+id/small_box_image"
android:layout_width="match_parent"
android:layout_height="150dp"
android:adjustViewBounds="true"
android:scaleType="centerCrop"
android:maxHeight="150dp"
android:background="@color/transparent"/>
<ImageView
android:layout_width="35dp"
android:layout_height="35dp"
android:layout_gravity="right"
android:src="@drawable/abc_btn_rating_star_off_mtrl_alpha"
/>
<TextView
android:id="@+id/small_box_type"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="@dimen/margin_normal"
android:paddingBottom="@dimen/margin_normal"
android:textSize="@dimen/font_small"
android:textColor="@color/font_white"
android:background="@drawable/small_box_text_bottom_border"
android:layout_gravity="bottom"
android:text="Object Story"
/>
</FrameLayout>
<TextView
android:id="@+id/small_box_title"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="@dimen/margin_larger"
android:layout_marginBottom="@dimen/margin_normal"
android:layout_marginRight="@dimen/margin_larger"
android:layout_marginTop="@dimen/margin_larger"
android:textSize="@dimen/font_large"
android:textColor="@color/font_black"
android:text="Sample Text Here"
/>
<TextView
android:id="@+id/small_box_desc"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="@dimen/margin_larger"
android:layout_marginBottom="@dimen/margin_larger"
android:textSize="@dimen/font_normal"
android:textColor="@color/font_black"
android:textStyle="italic"
android:text="Sample Text Here"
/>
</LinearLayout>
片段博物馆
<android.support.v4.widget.SwipeRefreshLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
tools:context="com.bluecadet.android.nasm.ui.AtTheMuseumFragment"
android:id="@+id/swipe_container"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_marginBottom="100dp">
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#FFFFFF"
android:descendantFocusability="blocksDescendants"
>
<TextView
android:id="@+id/museum_header"
style="@style/header"
android:text="@string/museum_header"
android:layout_margin="@dimen/margin_larger"
android:elevation="8dp"
/>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="275dp"
android:elevation="2dp"
>
<FrameLayout
android:id="@+id/museum_map"
android:layout_height="fill_parent"
android:layout_width="match_parent"
/>
<include
layout="@layout/view_explore_map" />
</FrameLayout>
<android.support.v7.widget.RecyclerView
android:id="@+id/stories_list_view"
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="@dimen/margin_normal"
android:layout_marginLeft="@dimen/margin_small"
android:layout_marginRight="@dimen/margin_small"
android:layout_marginTop="@dimen/margin_normal"
android:stretchMode="columnWidth"
/>
<Button
android:id="@+id/load_more"
style="@style/home_button"
android:gravity="center"
android:text="@string/button_load_more"
/>
</LinearLayout>
</ScrollView>
</android.support.v4.widget.SwipeRefreshLayout>
我现在正在玩的 ViewTreeObserver 代码。它在片段中。
mTopStoriesListView.setLayoutManager(new NewMeasuredStaggeredLayoutManager(2, StaggeredGridLayoutManager.VERTICAL, mTopStoriesListView));
mTopStoriesListView.setNestedScrollingEnabled(false);
//Testing Issue 54
final ViewTreeObserver viewTreeObserver = mTopStoriesListView.getViewTreeObserver();
if (viewTreeObserver.isAlive()) {
viewTreeObserver.addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
mTopStoriesListView.getViewTreeObserver().removeOnGlobalLayoutListener(this);
int l = 0,r = 0;
for(int i = 0 ; i < mNearMeAdapter.getItemCount(); i++){
int h = mTopStoriesListView.getLayoutManager().findViewByPosition(i).getHeight();
ViewGroup.MarginLayoutParams layout = (ViewGroup.MarginLayoutParams) mTopStoriesListView.getLayoutManager()
.findViewByPosition(i).getLayoutParams();
int t = layout.topMargin;
int b = layout.bottomMargin;
if(i % 2 == 0){
l += h + t + b;
}else{
r += h + t + b;
}
}
int viewHeight = (l > r) ? l : r;
mTopStoriesListView.getLayoutParams().height = viewHeight;
Log.d("TAG", String.valueOf(viewHeight));
}
});
}
//END TEST