Android 为什么父母不匹配';回收器视图项根为LinearLayout时不工作?
我简化了代码以显示问题 Mainactivity.javaAndroid 为什么父母不匹配';回收器视图项根为LinearLayout时不工作?,android,xml,android-linearlayout,android-recyclerview,Android,Xml,Android Linearlayout,Android Recyclerview,我简化了代码以显示问题 Mainactivity.java public class MainActivity extends AppCompatActivity { private RecyclerView mRecyclerView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); set
public class MainActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);
ItemData itemsData[] = { new ItemData("test 1"),
new ItemData("test 2"),
new ItemData("test 3")};
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
MyAdapter mAdapter = new MyAdapter(itemsData, this);
mRecyclerView.setAdapter(mAdapter);
mRecyclerView.setItemAnimator(new DefaultItemAnimator());
}
}
MyAdapter.java
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
static Context mContext;
private ItemData[] itemsData;
public MyAdapter(ItemData[] itemsData, Context context) {
this.itemsData = itemsData;
mContext = context;
}
@Override
public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemLayoutView = LayoutInflater.from(parent.getContext())
.inflate(R.layout.item_layout, null);
ViewHolder viewHolder = new ViewHolder(itemLayoutView);
return viewHolder;
}
@Override
public void onBindViewHolder(ViewHolder viewHolder, int position) {
viewHolder.txtViewTitle.setText(itemsData[position].getTitle());
}
public static class ViewHolder extends RecyclerView.ViewHolder {
public TextView txtViewTitle;
public ViewHolder(View itemLayoutView) {
super(itemLayoutView);
txtViewTitle = (TextView) itemLayoutView.findViewById(R.id.item_title);
}
}
@Override
public int getItemCount() {
return itemsData.length;
}
}
activity_main.xml
<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:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin" tools:context=".MainActivity">
<android.support.v7.widget.RecyclerView
android:id="@+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent">
</android.support.v7.widget.RecyclerView>
</RelativeLayout>
item_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="80dp">
<TextView
android:id="@+id/item_title"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textColor="@android:color/background_dark"
android:background="@android:color/holo_blue_bright"
android:layout_marginLeft="8dp"
android:layout_marginRight="8dp"
android:layout_marginTop="8dp"
android:textSize="22dp" />
</RelativeLayout>
当我在item_layout.xml中将LinearLayout更改为RelativeLayout时,它可以正常工作,但当我使用LinearLayout时,它会忽略匹配父项。
我需要在不将LinearLayout更改为RelativeLayout的情况下使其正常工作。使用RecyclerView时,需要指定一个LayoutManager,负责在视图中布局每个项目。LinearLayoutManager允许您指定方向,就像普通的LinearLayout一样。可以尝试权重和权重和属性吗 代码:
LinearLayoutManager layoutManager
= new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false);
RecyclerView myList = findViewById(R.id.my_recycler_view);
myList.setLayoutManager(layoutManager)
只需将项目视图的膨胀方式更改为:
View itemLayoutView = LayoutInflater.from(parent.getContext())
.inflate(R.layout.item_layout, parent, false);
将父对象传递给充气机,充气机可以知道应该使用哪个布局参数。第三个参数表示是否应将视图附加到父视图。在向下投票时,请说明原因。这有助于改善这个答案,同样的问题。可能是支持库的错误?
View itemLayoutView = LayoutInflater.from(parent.getContext())
.inflate(R.layout.item_layout, parent, false);