我正在尝试为要进入学校应用程序的清单创建卡片视图。 ArrayList中的所有项目都进入一张卡，我不知道为什么。我看了所有可以找到的教程，但是没有运气。
这是相关的代码。任何帮助都将不胜感激。
活动
recyclerView = (RecyclerView) findViewById(R.id.masterListRecView);
recyclerView.setHasFixedSize(true);
layoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(layoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
theList = new ArrayList<MasterListItem>();
theList.add(new MasterListItem("Test Item1",new Date(),new Date(),"here are some notes",false));
theList.add(new MasterListItem("Test Item2",new Date(),new Date(),"here are some notes",false));
theList.add(new MasterListItem("Test Item3",new Date(),new Date(),"here are some notes",false));
theList.add(new MasterListItem("Test Item4",new Date(),new Date(),"here are some notes",false));
theList.add(new MasterListItem("Test Item5",new Date(),new Date(),"here are some notes",false));
theList.add(new MasterListItem("Test Item6",new Date(),new Date(),"here are some notes",false));
theList.add(new MasterListItem("Test Item7",new Date(),new Date(),"here are some notes",false));
theList.add(new MasterListItem("Test Item8",new Date(),new Date(),"here are some notes",false));
theList.add(new MasterListItem("Test Item9",new Date(),new Date(),"here are some notes",false));
theList.add(new MasterListItem("Test Item10",new Date(),new Date(),"here are some notes",false));
masterListAdapter = new RecViewAdapter(theList);
recyclerView.setAdapter(masterListAdapter);
masterListAdapter.notifyDataSetChanged();
RecycleView适配器
public class RecViewAdapter extends RecyclerView.Adapter<RecViewAdapter.MyViewHolder> {
TextView title;
TextView dueDate;
TextView completedDate;
TextView notes;
CheckBox completed;
private ArrayList<MasterListItem> theList;
//private LayoutInflater inflater;
public RecViewAdapter(ArrayList<MasterListItem> theList) {
this.theList = theList;
//inflater = LayoutInflater.from(context);
}
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.master_list_item,parent,false);
MyViewHolder myViewHolder = new MyViewHolder(view);
return myViewHolder;
}
@Override
public void onBindViewHolder(MyViewHolder holder, int position) {
title = holder.title;
dueDate = holder.dueDate;
completedDate = holder.completedDate;
notes = holder.notes;
completed = holder.completed;
title.setText(theList.get(position).getTitle());
dueDate.setText(theList.get(position).getDueDate().toString());
completedDate.setText(theList.get(position).getCompletedDate().toString());
notes.setText(theList.get(position).getNotes());
completed.setChecked(theList.get(position).isCompleted());
}
@Override
public int getItemCount() {
return theList.size();
}
@Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
super.onAttachedToRecyclerView(recyclerView);
}
public class MyViewHolder extends RecyclerView.ViewHolder{
private TextView title;
private TextView dueDate;
private TextView completedDate;
private TextView notes;
private CheckBox completed;
public MyViewHolder(View itemView){
super(itemView);
this.title = (TextView) itemView.findViewById(R.id.masterListTitle);
this.dueDate = (TextView) itemView.findViewById(R.id.masterListDueDate);
this.completedDate = (TextView) itemView.findViewById(R.id.masterListCompletedDate);
this.notes = (TextView) itemView.findViewById(R.id.masterListNotes);
this.completed = (CheckBox) itemView.findViewById(R.id.masterListCompleted);
}
}
}
RecycleView XML
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="edu.uco.weddingcrashers.hitched.MasterWeddingList">
<Button
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="+"
android:id="@+id/addTaskButton"
android:layout_alignParentTop="true"
android:layout_alignParentEnd="true" />
<android.support.v7.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="vertical"
android:id="@+id/masterListRecView"
>
</android.support.v7.widget.RecyclerView>
</RelativeLayout>
卡XML
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
android:id="@+id/masterListCardView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
card_view:cardCornerRadius="4dp"
xmlns:android="http://schemas.android.com/apk/res/android">
<!--
android:layout_alignParentStart="true"
android:layout_gravity="center"
android:layout_below="@+id/addTaskButton"
-->
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/masterListTitle"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="test title" />
<TextView
android:id="@+id/masterListDueDate"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="test title" />
<TextView
android:id="@+id/masterListCompletedDate"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="test title" />
<TextView
android:id="@+id/masterListNotes"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="test title" />
<CheckBox
android:id="@+id/masterListCompleted"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Completed"
android:editable="false"
android:layout_gravity="center_horizontal" />
</LinearLayout>
</android.support.v7.widget.CardView>
再次非常感谢！
最佳答案
您必须在RecyclerView项目之间添加分隔线。向RecyclerView添加分隔线和装饰与其他列表视图不同。您可以通过以下答案来实现：
与ListView不同，RecyclerView类没有与分隔符相关的参数。相反，您需要扩展RecyclerView的内部类ItemDecoration：
ItemDecoration允许应用程序添加特殊图形并
适配器数据集中特定项目视图的布局偏移量。这个
可用于在项目，高光，视觉之间绘制分隔线
分组边界等等。
所有ItemDecorations均按添加顺序绘制，
项目视图（在onDraw()中和项目之后（在onDrawOver(Canvas, RecyclerView, RecyclerView.State)中）。
垂直间距ItemDecoration
扩展ItemDecoration，添加将空格高度作为参数的自定义构造函数，并覆盖getItemOffsets()：
public class VerticalSpaceItemDecoration extends RecyclerView.ItemDecoration {
private final int mVerticalSpaceHeight;
public VerticalSpaceItemDecoration(int mVerticalSpaceHeight) {
this.mVerticalSpaceHeight = mVerticalSpaceHeight;
}
@Override
public void getItemOffsets(Rect outRect, View view, RecyclerView parent,
RecyclerView.State state) {
outRect.bottom = mVerticalSpaceHeight;
}
}
如果不想在最后一项下方插入空格，请添加以下条件：
if (parent.getChildAdapterPosition(view) !=
parent.getAdapter().getItemCount() - 1) {
outRect.bottom = mVerticalSpaceHeight;
}
注意：您也可以修改outRect.top，outRect.left和outRect.right属性以获得所需的效果。
分频器项装饰
扩展ItemDecoration并覆盖
onDraw()：public class DividerItemDecoration extends RecyclerView.ItemDecoration {
private static final int[] ATTRS = new int[]{android.R.attr.listDivider};
private Drawable mDivider;
/**
* Default divider will be used
*/
public DividerItemDecoration(Context context) {
final TypedArray styledAttributes = context.obtainStyledAttributes(ATTRS);
mDivider = styledAttributes.getDrawable(0);
styledAttributes.recycle();
}
/**
* Custom divider will be used
*/
public DividerItemDecoration(Context context, int resId) {
mDivider = ContextCompat.getDrawable(context, resId);
}
@Override
public void onDraw(Canvas c, RecyclerView parent, RecyclerView.State state) {
int left = parent.getPaddingLeft();
int right = parent.getWidth() - parent.getPaddingRight();
int childCount = parent.getChildCount();
for (int i = 0; i < childCount; i++) {
View child = parent.getChildAt(i);
RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
int top = child.getBottom() + params.bottomMargin;
int bottom = top + mDivider.getIntrinsicHeight();
mDivider.setBounds(left, top, right, bottom);
mDivider.draw(c);
}
}
}
您可以调用第一个使用默认Android除法器属性的构造函数，也可以调用第二个使用您自己的drawable的构造函数，例如drawable / divider.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<size
android:height="1dp" />
<solid android:color="#ff992900" />
</shape>
注意：如果要在项目上绘制分隔线，请改写
onDrawOver()。用法
要使用您的新类，例如在片段的
onCreateView()中，将VerticalSpaceItemDecoration或DividerSpaceItemDecoration添加到RecyclerView中：private static final int VERTICAL_ITEM_SPACE = 48;
private RecyclerView mUiRecyclerView;
private LinearLayoutManager mLinearLayoutManager;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_feed, container, false);
mUiRecyclerView = (RecyclerView) rootView.findViewById(R.id.fragment_home_recycler_view);
mLinearLayoutManager = new LinearLayoutManager(getActivity());
mUiRecyclerView.setLayoutManager(mLinearLayoutManager);
//add ItemDecoration
mUiRecyclerView.addItemDecoration(new VerticalSpaceItemDecoration(VERTICAL_ITEM_SPACE));
//or
mUiRecyclerView.addItemDecoration(
new DividerItemDecoration(getActivity());
//or
mUiRecyclerView.addItemDecoration(
new DividerItemDecoration(getActivity(), R.drawable.divider));
mUiRecyclerView.setAdapter(...);
return rootView;
}
还有Lucas Rocha的图书馆，应该可以简化物品装饰过程。还没有尝试过。
其功能包括：
库存物品装饰的集合，包括：
项目间距水平/垂直分隔线。
项目清单