Java 使用自定义对象的arrayList填充listview
我已经在android上试了几周了,但在用自定义对象填充listview时遇到了一个障碍。我试过几个关于stack overflow和youtube的教程,但当应用程序运行时,它在list.setAdapter(adapter)处崩溃。但我不知道原因是什么 以下是我最近的一次尝试:Java 使用自定义对象的arrayList填充listview,java,android,listview,custom-adapter,Java,Android,Listview,Custom Adapter,我已经在android上试了几周了,但在用自定义对象填充listview时遇到了一个障碍。我试过几个关于stack overflow和youtube的教程,但当应用程序运行时,它在list.setAdapter(adapter)处崩溃。但我不知道原因是什么 以下是我最近的一次尝试: public class NPCEditor extends Fragment{ View myView; ArrayList<NPC> NPCs = new ArrayList<
public class NPCEditor extends Fragment{
View myView;
ArrayList<NPC> NPCs = new ArrayList<>();
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
myView = inflater.inflate(R.layout.npc_edit, container, false);
populateNPCList();
populateListview();
return myView;
}
private void populateNPCList(){
NPCs.add(new NPC(40, 10, 10, 10, 10, 10, 10, "", "", "", "", "", "", ""));
NPCs.add(new NPC(50, 10, 10, 10, 10, 10, 10, "", "", "", "", "", "", ""));
NPCs.add(new NPC(60, 10, 10, 10, 10, 10, 10, "", "", "", "", "", "", ""));
NPCs.add(new NPC(70, 10, 10, 10, 10, 10, 10, "", "", "", "", "", "", ""));
NPCs.add(new NPC(80, 10, 10, 10, 10, 10, 10, "", "", "", "", "", "", ""));
}
private void populateListview(){
ArrayAdapter<NPC> adapter = new NPCAdapter2();
ListView list = myView.findViewById(R.id.NPCList);
list.setAdapter(adapter);
}
private class NPCAdapter2 extends ArrayAdapter<NPC>{
public NPCAdapter2(){
super(getActivity(), R.layout.npc_layout, NPCs);
}
public View getView(int position, View convertView, ViewGroup parent){
View itemView = convertView;
if(itemView == null){
itemView = getLayoutInflater().inflate(R.layout.npc_layout, parent, false);
}
NPC currentNPC = NPCs.get(position);
TextView txtAge = itemView.findViewById(R.id.textAge);
txtAge.setText(currentNPC.getAge());
return itemView;
}
}
}
公共类NPCEditor扩展片段{
查看我的视图;
ArrayList NPCs=新的ArrayList();
@可空
@凌驾
创建视图时的公共视图(LayoutFlater充气机、@Nullable ViewGroup容器、Bundle savedInstanceState){
myView=充气机。充气(R.layout.npc_编辑,容器,false);
populateNPCList();
populateListview();
返回myView;
}
私有void populateNPCList(){
添加(新NPC(40,10,10,10,10,10,10,10,10,10,10,“,”,“,”,“,”,“,”,”);
添加(新NPC(50,10,10,10,10,10,10,10,10,10,10,“,”,“,”,“,”,“,”,”);
添加(新NPC(60,10,10,10,10,10,10,10,10,10,10,“,”,“,”,“,”,“,”,”);
添加(新NPC(70,10,10,10,10,10,10,10,10,10,10,“,”,“,”,“,”,“,”,”);
添加(新NPC(80,10,10,10,10,10,10,10,10,10,10,“,”“,”“,”“,”“,”“,”“,”“);
}
私有void populateListview(){
ArrayAdapter适配器=新的NPCAdapter2();
ListView list=myView.findviewbyd(R.id.NPCList);
list.setAdapter(适配器);
}
私有类NPCAdapter2扩展了ArrayAdapter{
公共NPCAdapter2(){
super(getActivity(),R.layout.npc_layout,NPCs);
}
公共视图getView(int位置、视图转换视图、视图组父视图){
视图项视图=转换视图;
如果(itemView==null){
itemView=GetLayoutFlater()。充气(R.layout.npc\u布局,父级,false);
}
NPC currentNPC=NPCs.get(位置);
TextView txtAge=itemView.findviewbyd(R.id.textAge);
setText(currentNPC.getAge());
返回项目视图;
}
}
}
以及xml文件
npc_布局
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/textAge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="Age" />
</LinearLayout>
和NPCEditor布局:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ListView
android:id="@+id/NPCList"
android:layout_width="368dp"
android:layout_height="327dp"
android:layout_marginBottom="16dp"
android:layout_marginStart="8dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent" />
</android.support.constraint.ConstraintLayout>
日志:
坠机开始
04-22 10:43:56.986 12587-12587/blackanvil.com.dmi E/AndroidRuntime:>致命异常:main
流程:blackanvil.com.dmi,PID:12587
java.lang.NoSuchMethodError:没有虚拟方法
getLayoutFlater()Landroid/view/LayoutFlater;课堂上
Lblackanvil/com/dmi/NPCEditor;或者它的超类(声明
“blackanvil.com.dmi.NPCEditor”出现在
/data/app/blackanvil.com.dmi-1/split_lib_slice_2_apk.apk)
位于blackanvil.com.dmi.NPCEditor$NPCAdapter2.getView(NPCEditor.java:53)
在android.widget.AbsListView.obtainView(AbsListView.java:2497)上
位于android.widget.ListView.makeAndAddView(ListView.java:1930)
在android.widget.ListView.fillDown(ListView.java:722)中
位于android.widget.ListView.fillFromTop(ListView.java:783)
位于android.widget.ListView.layoutChildren(ListView.java:1721)
在android.widget.AbsListView.onLayout(AbsListView.java:2254)
位于android.view.view.layout(view.java:16966)
位于android.view.ViewGroup.layout(ViewGroup.java:5604)
在
android.support.constraint.ConstraintLayout.onLayout(ConstraintLayout.java:1855)
位于android.view.view.layout(view.java:16966)
位于android.view.ViewGroup.layout(ViewGroup.java:5604)
在android.widget.FrameLayout.layoutChildren(FrameLayout.java:398)中
位于android.widget.FrameLayout.onLayout(FrameLayout.java:333)
位于android.view.view.layout(view.java:16966)
位于android.view.ViewGroup.layout(ViewGroup.java:5604)
在
android.support.constraint.ConstraintLayout.onLayout(ConstraintLayout.java:1855)
位于android.view.view.layout(view.java:16966)
位于android.view.ViewGroup.layout(ViewGroup.java:5604)
在
HeaderScrollingViewBehavior.layoutChild(HeaderScrollingViewBehavior.java:132)
在
android.support.design.widget.ViewOffsetBehavior.onLayoutChild(ViewOffsetBehavior.java:42)
在
android.support.design.widget.AppBarLayout$ScrollingViewBehavior.onLayoutChild(AppBarLayout.java:1361)
在
android.support.design.widget.CoordinatorLayout.onLayout(CoordinatorLayout.java:869)
itemView = LayoutInflater.from(getContext()).inflate(R.layout.npc_layout, parent, false);