Question

所以我在custom adapter for listview in fragment Android

上关注了@AndiGeeky的回答

但它没有用。这是我的代码。

public class TabLectura extends Fragment implements View.OnClickListener {

private View view;
private ListView list_calllog;
private static final String ARG_SECTION_NUMBER = "section_number";
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState)
{
    if(view==null)
    {
        view=inflater.inflate(R.layout.tab_lectura, container,false);
    }
    else
    {
        ViewGroup parent = (ViewGroup) view.getParent();
        parent.removeView(view);
    }

    ClassOrdenDetalle detalle = new ClassOrdenDetalle(123,"321",15,15);
    ArrayList<ClassOrdenDetalle> ordeness = new ArrayList<>();
    ordeness.add(detalle);
    MyTableAdapter adapter=new MyTableAdapter(getActivity(),R.layout.list_item_table,ordeness);
    list_calllog=(ListView)view.findViewById(R.id.tableArticulosView);
    list_calllog.setAdapter(adapter);
    return view;
}



public static TabLectura newInstance(int sectionNumber) {
    TabLectura fragment = new TabLectura();
    Bundle args = new Bundle();
    args.putInt(ARG_SECTION_NUMBER, sectionNumber);
    fragment.setArguments(args);
    return fragment;
}

@Override
public void onClick(View v) {

}

@Override
public void  onActivityResult(int requestCode, int resultCode, Intent intent) {
    if (requestCode == 0) {
        if (resultCode == getActivity().RESULT_OK) {

            String contents = intent.getStringExtra("SCAN_RESULT");
            String format = intent.getStringExtra("SCAN_RESULT_FORMAT");

            Toast.makeText(getActivity(),"SCAN_RESULT --- >>>   " + contents ,
                    Toast.LENGTH_LONG).show();
            // Handle successful scan

        } else if (resultCode == getActivity().RESULT_CANCELED) {
            Toast.makeText(getActivity(),"Error" ,
                    Toast.LENGTH_LONG).show();
        }
    }
}

class MyTableAdapter extends ArrayAdapter<ClassOrdenDetalle> {

    Context context;
    int layoutResourceId;
    ArrayList<ClassOrdenDetalle> data = null;

    public MyTableAdapter(Context mContext, int layoutResourceId, ArrayList<ClassOrdenDetalle> data) {

        super(mContext, layoutResourceId, data);

        this.layoutResourceId = layoutResourceId;
        this.context = mContext;
        this.data = data;
    }

    @Override
    public View getView(final int position, View convertView, ViewGroup parent) {


        LayoutInflater inflater=(LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        view=inflater.inflate(layoutResourceId, parent,false);
        ClassOrdenDetalle item = data.get(position);
        Holder holder=new Holder();
        holder.text_cantidad=(TextView)view.findViewById(R.id.txtcantidad);
        holder.text_codigo=(TextView)view.findViewById(R.id.txtarticulo);
        holder.text_codigo.setText(item.getCod_articulo());
        holder.text_cantidad.setText(item.getCantidad()+"");
        return view;
    }

    public class Holder
    {
        TextView text_codigo;
        TextView text_cantidad;
    }

}}

这是我的tab_lectura.xml

<android.support.v4.widget.NestedScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
android:layout_width="match_parent"
android:fillViewport="true"
android:layout_gravity="fill_vertical"
android:layout_height="match_parent">

<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <LinearLayout
        android:padding="15dp"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:weightSum="1">
        <LinearLayout
            android:orientation="horizontal"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_margin="10dp">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="match_parent"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:text="Nro Orden"
                android:textColor="@color/colorPrimaryDark"
                android:id="@+id/textView3" />

            <Spinner
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:id="@+id/spinner" />
        </LinearLayout>
        <LinearLayout
                android:orientation="horizontal"
                android:layout_width="match_parent"
                android:layout_height="80dp"
                android:paddingTop="10dp"
            android:layout_margin="10dp">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:text="Contenedor"
                android:textColor="@color/colorPrimaryDark"
                android:id="@+id/textView2" />

            <EditText
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:inputType="number"
                    android:paddingLeft="10dp"
                    android:id="@+id/edtContenedor" />

        </LinearLayout>
        <LinearLayout
            android:orientation="horizontal"
            android:layout_width="match_parent"
            android:weightSum="2"
            android:layout_height="match_parent">

            <TextView
                android:layout_width="0dp"
                android:id="@+id/txtarticulo"
                android:layout_height="wrap_content"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:layout_weight="1"
                android:text="Articulo"
                android:textColor="@color/colorPrimaryDark" />
            <TextView
                android:layout_width="0dp"
                android:id="@+id/txtcantidad"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:textAppearance="?android:attr/textAppearanceMedium"
                android:text="Cantidad"
                android:textColor="@color/colorPrimaryDark" />
        </LinearLayout>
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent">
            <ListView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/tableArticulosView" />
        </LinearLayout>
        <LinearLayout
            android:orientation="horizontal"
            android:layout_width="match_parent"
            android:layout_height="match_parent">

            <ImageButton
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:id="@+id/btnQRCode"
                android:src="@mipmap/qr_code"
                android:background="@null"
                android:layout_weight="1"
                android:layout_gravity="right" />

            <Button
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Guardar"
                android:layout_weight="1"
                android:background="@color/colorPrimary"
                android:id="@+id/button"
                android:layout_gravity="center_horizontal"
                android:layout_alignParentTop="true"
                android:layout_centerHorizontal="true" />

        </LinearLayout>
    </LinearLayout>

</FrameLayout></android.support.v4.widget.NestedScrollView>

这是我的list_item_table.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
android:padding="5dp" >

<!-- Tag value -->
<LinearLayout
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:orientation="vertical"
    android:layout_gravity="center_vertical" >

    <TextView android:id="@+id/article_code"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center_vertical"
        android:textSize="14sp" />

</LinearLayout>

<View android:layout_width="3dp" android:layout_height="3dp" />

<!-- Tag count -->
<TextView android:id="@+id/article_count"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_weight="1"
    android:layout_gravity="center_vertical|end"
    android:gravity="center_vertical|center"
    android:textStyle="bold"
    android:textSize="14sp" /></LinearLayout>

LOGCAT错误

09-19 15:23:07.939 13248-13248/? E/AndroidRuntime: FATAL EXCEPTION: main java.lang.NullPointerException
at com.todosoft.frutifor.TabLectura$MyTableAdapter.getView(TabLectura.java:120)
at android.widget.AbsListView.obtainView(AbsListView.java:2177)
at android.widget.ListView.onMeasure(ListView.java:1131)
at android.view.View.measure(View.java:15848)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5012)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1052)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:590)
at android.view.View.measure(View.java:15848)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5012)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
at android.view.View.measure(View.java:15848)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5012)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
at android.view.View.measure(View.java:15848)
at android.support.v4.widget.NestedScrollView.measureChildWithMargins(NestedScrollView.java:1415)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
at android.support.v4.widget.NestedScrollView.onMeasure(NestedScrollView.java:480)
at android.view.View.measure(View.java:15848)
at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1560)
at android.view.View.measure(View.java:15848)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5012)
at android.support.design.widget.CoordinatorLayout.onMeasureChild(CoordinatorLayout.java:668)
at android.support.design.widget.CoordinatorLayout.onMeasure(CoordinatorLayout.java:735)
at android.view.View.measure(View.java:15848)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5012)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:135)
at android.view.View.measure(View.java:15848)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5012)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
at android.view.View.measure(View.java:15848)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5012)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
at android.view.View.measure(View.java:15848)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5012)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
at android.view.View.measure(View.java:15848)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5012)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2189)
at android.view.View.measure(View.java:15848)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1905)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1104)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1284)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1004)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:5481)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:749)
at android.view.Choreographer.doCallbacks(Choreographer.java:562)
at android.view.Choreographer.doFrame(Choreographer.java:532)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:735)
at android.os.Handler.handleCallback(Handler.java:730)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Loope09-19 15:28:08.072 1324813248/com.todosoft.frutiforI/Process: Sending signal. PID: 13248 SIG: 9

这是行错误

holder.text_codigo.setText(item.getCod_articulo());

因为holder.text_codigo是null。

提前感谢您的帮助，并对不良内容（仅限于stackoverflow）感到抱歉，我是创建帖子的新手。

Answer 1

@Override
public View getView(final int position, View convertView, ViewGroup parent) {

    View view = convertView;
    Holder holder;
    if (view == null) {
        LayoutInflater inflater= LayoutInflater.from(parent.getContext());
        view = inflater.inflate(layoutResourceId, parent, false);

        holder = new Holder();
        holder.text_cantidad=(TextView) view.findViewById(R.id.article_count);
        holder.text_codigo=(TextView) view.findViewById(R.id.article_code);

        view.setTag(holder);
    } else {
        holder = (Holder) view.getTag();
    }


    ClassOrdenDetalle item = data.get(position);
    holder.text_codigo.setText(item.getCod_articulo());
    holder.text_cantidad.setText(item.getCantidad()+"");

    return view;
}

Answer 2

@Override
public View getView(final int position, View convertView, ViewGroup parent) {

    Context context = activity.getApplicationContext();
    if (convertView == null) {
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        convertView = inflater.inflate(layoutResourceId, null);
    }

    ClassOrdenDetalle item = data.get(position);
    Holder holder=new Holder();
    holder.text_cantidad=(TextView)convertView.findViewById(R.id.txtcantidad);
    holder.text_codigo=(TextView)convertView.findViewById(R.id.txtarticulo);
    holder.text_codigo.setText(item.getCod_articulo());
    holder.text_cantidad.setText(item.getCantidad()+"");
    return view;
}

片段内ListView的自定义适配器

2 个答案: