1

一旦调用 setadapter 函数,我的应用程序就会崩溃,我很难过。根据 logcat,这是一些空异常,但我似乎无法找出问题所在。任何帮助表示赞赏!

这是我的主要

package com.example.ridehistory;



import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ListView;
import android.support.v4.app.NavUtils;
import android.annotation.TargetApi;
import android.os.Build;

public class MainActivity extends Activity {

    private ListView rideHistoryListView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        // Show the Up button in the action bar.
        //setupActionBar();

        //Initialize for fake data
        ArrayList<String> array1 = new ArrayList<String>();
        array1.add("first passenger1");
        ArrayList<String> array2 = new ArrayList<String>();
        array2.add("first passenger2");
        ArrayList<String> array3 = new ArrayList<String>();
        array3.add("first passenger3");
        ArrayList<String> array4 = new ArrayList<String>();
        array4.add("first passenger4");
        ArrayList<String> array5 = new ArrayList<String>();
        array5.add("first passenger5");

        SimpleDateFormat date1 = new SimpleDateFormat("1/2/80");
        SimpleDateFormat date2 = new SimpleDateFormat("2/3/80");
        SimpleDateFormat date3 = new SimpleDateFormat("3/4/80");
        SimpleDateFormat date4 = new SimpleDateFormat("4/5/80");
        SimpleDateFormat date5 = new SimpleDateFormat("5/6/80");

        //Start of the actual code
        RideTransaction ride_data[] = new RideTransaction[]
                {
                    new RideTransaction("A","Last",array1,"sf","la",date1),
                    new RideTransaction("B", "Last", array2, "la", "sd", date2),
                    new RideTransaction("C", "Last", array3, "sf", "ny", date3),
                    new RideTransaction("D", "Last", array4, "sf", "sd", date4),
                    new RideTransaction("E" , "Last", array5, "irvine", "la", date5)
                };
        RideHistoryAdapter adapter = new RideHistoryAdapter(this,
                                                            R.layout.listview_item_row,
                                                            ride_data);

        rideHistoryListView = (ListView)findViewById(R.id.rideHistoryListView);
        //RideHistoryAdapter adapter = new RideHistoryAdapter(this);

        View header = (View)getLayoutInflater().inflate(R.layout.listview_header_row, null);
        rideHistoryListView.addHeaderView(header);
        rideHistoryListView.setAdapter(adapter);
    }

    /**
     * Set up the {@link android.app.ActionBar}, if the API is available.
     */
    /*
    @TargetApi(Build.VERSION_CODES.HONEYCOMB)
    private void setupActionBar() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
            getActionBar().setDisplayHomeAsUpEnabled(true);
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.ride_history, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
        case android.R.id.home:
            // This ID represents the Home or Up button. In the case of this
            // activity, the Up button is shown. Use NavUtils to allow users
            // to navigate up one level in the application structure. For
            // more details, see the Navigation pattern on Android Design:
            //
            // http://developer.android.com/design/patterns/navigation.html#up-vs-back
            //
            NavUtils.navigateUpFromSameTask(this);
            return true;
        }
        return super.onOptionsItemSelected(item);
    }*/

}

这是我的适配器

package com.example.ridehistory;

import android.app.Activity;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;

public class RideHistoryAdapter extends ArrayAdapter<RideTransaction>{
    Context context;
    int layoutResourceId;
    RideTransaction data[] = null;

    public RideHistoryAdapter(Context context, int layoutResourceId, RideTransaction[] data)
    {
        super( context, layoutResourceId, data);
        this.context = context;
        this.layoutResourceId = layoutResourceId;
        this.data = data;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent)
    {
        View row = convertView;
        RideTransactionHolder holder = null;

        if(row == null)
        {
            LayoutInflater inflater = ((Activity)context).getLayoutInflater();
            row = inflater.inflate(layoutResourceId, parent, false);

            holder = new RideTransactionHolder();
            holder.txtFirstName = (TextView)row.findViewById(R.id.txtFirstName);
            holder.txtLastName = (TextView)row.findViewById(R.id.txtLastName);
            holder.txtPassengers = (TextView)row.findViewById(R.id.txtPassengers);
            holder.txtStartLocation = (TextView)row.findViewById(R.id.txtStartLocation);
            holder.txtEndLocation = (TextView)row.findViewById(R.id.txtEndLocation);

            row.setTag(holder);
        }
        else
        {
            holder = (RideTransactionHolder)row.getTag();
        }

        RideTransaction rideTransaction = data[position];
        holder.txtFirstName.setText(rideTransaction.firstName);
        holder.txtLastName.setText(rideTransaction.lastName);
        holder.txtPassengers.setText("hmm");
        holder.txtStartLocation.setText(rideTransaction.startLocation);
        holder.txtEndLocation.setText(rideTransaction.endLocation);
        holder.txtDateTime.setText(rideTransaction.dateTime.toString());

        return row;
    }

    static class RideTransactionHolder
    {
        TextView txtFirstName;
        TextView txtLastName;
        TextView txtPassengers;
        TextView txtStartLocation;
        TextView txtEndLocation;
        TextView txtDateTime;
    }
}

这是搭车交易

package com.example.ridehistory;

import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;

public class RideTransaction {
    public String firstName;
    public String lastName;
    public ArrayList<String> passengers;
    //some kind promptness rating..?
    public String startLocation;
    public String endLocation;
    public SimpleDateFormat dateTime;


    public RideTransaction()
    {
        super();
    }

    public RideTransaction(String firstName, String lastName, ArrayList<String> passengers, String startLocation, String endLocation, SimpleDateFormat dateTime)
    {
        this.firstName = firstName;
        this.lastName = lastName;
        this.passengers = passengers;
        this.startLocation = startLocation;
        this.endLocation = endLocation;
        this.dateTime = dateTime;
    }
}

这是主要的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: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=".MainActivity" >


    <ListView
        android:id="@+id/rideHistoryListView"
        android:layout_width = "fill_parent"
        android:layout_height="fill_parent"
        />

</RelativeLayout>

这是项目行 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="fill_parent"
    android:padding="10dp">

    <TextView
        android:id="@+id/txtDateTime"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:gravity="center_horizontal"
        android:text="date"
        />

    <TextView 
        android:id="@+id/txtFirstName"
        android:layout_width="wrap_content"
        android:layout_height = "wrap_content"
        android:gravity="center_horizontal"
        android:layout_below="@id/txtDateTime"
        android:text="first"
        />
    <TextView 
        android:id="@+id/txtLastName"
        android:layout_width="wrap_content"
        android:layout_height = "wrap_content"
        android:layout_alignParentTop="true"
        android:layout_toRightOf="@id/txtFirstName"
        android:layout_below="@id/txtDateTime"
        android:gravity="center_horizontal"
        android:text="last"
        />
    <TextView
        android:id="@+id/txtPassengers"
        android:layout_width = "wrap_content"
        android:layout_height = "wrap_content"
        android:gravity="center_horizontal"
        android:layout_below="@id/txtFirstName"
        android:text="passengers"
        />
    <TextView
        android:id="@+id/txtStartLocation"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:gravity="center_horizontal"
        android:layout_below="@id/txtPassengers"
        android:text="start"
        />
    <TextView
        android:id="@+id/txtEndLocation"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/txtPassengers"
        android:layout_toRightOf="@id/txtStartLocation"
        android:gravity="center_horizontal"
        android:text="end"
        />

</RelativeLayout>

这是项目标题

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="horizontal" 
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"> 

     <TextView android:id="@+id/txtHeader"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:gravity="center_vertical"
        android:layout_alignParentTop="true"
        android:layout_alignParentBottom="true"
        android:textStyle="bold"
        android:textSize="22dp"
        android:textColor="#FFFFFF"
        android:padding="10dp"
        android:text="Ride Transaction"
        android:background="#336699" />

</LinearLayout>

这是我的日志猫

05-03 01:26:27.087: W/dalvikvm(272): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
05-03 01:26:27.107: E/AndroidRuntime(272): FATAL EXCEPTION: main
05-03 01:26:27.107: E/AndroidRuntime(272): java.lang.NullPointerException
05-03 01:26:27.107: E/AndroidRuntime(272):  at com.example.ridehistory.RideHistoryAdapter.getView(RideHistoryAdapter.java:52)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.HeaderViewListAdapter.getView(HeaderViewListAdapter.java:220)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.AbsListView.obtainView(AbsListView.java:1315)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.ListView.makeAndAddView(ListView.java:1727)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.ListView.fillDown(ListView.java:652)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.ListView.fillFromTop(ListView.java:709)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.ListView.layoutChildren(ListView.java:1580)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.AbsListView.onLayout(AbsListView.java:1147)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.view.View.layout(View.java:7035)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.RelativeLayout.onLayout(RelativeLayout.java:909)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.view.View.layout(View.java:7035)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.view.View.layout(View.java:7035)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1249)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1125)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.LinearLayout.onLayout(LinearLayout.java:1042)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.view.View.layout(View.java:7035)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.view.View.layout(View.java:7035)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.view.ViewRoot.performTraversals(ViewRoot.java:1045)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.view.ViewRoot.handleMessage(ViewRoot.java:1727)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.os.Handler.dispatchMessage(Handler.java:99)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.os.Looper.loop(Looper.java:123)
05-03 01:26:27.107: E/AndroidRuntime(272):  at android.app.ActivityThread.main(ActivityThread.java:4627)
05-03 01:26:27.107: E/AndroidRuntime(272):  at java.lang.reflect.Method.invokeNative(Native Method)
05-03 01:26:27.107: E/AndroidRuntime(272):  at java.lang.reflect.Method.invoke(Method.java:521)
05-03 01:26:27.107: E/AndroidRuntime(272):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-03 01:26:27.107: E/AndroidRuntime(272):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-03 01:26:27.107: E/AndroidRuntime(272):  at dalvik.system.NativeStart.main(Native Method)
05-03 01:26:36.588: I/Process(272): Sending signal. PID: 272 SIG: 9
05-03 04:13:50.917: D/AndroidRuntime(586): Shutting down VM
05-03 04:13:50.917: W/dalvikvm(586): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
05-03 04:13:50.937: E/AndroidRuntime(586): FATAL EXCEPTION: main
05-03 04:13:50.937: E/AndroidRuntime(586): java.lang.NullPointerException
05-03 04:13:50.937: E/AndroidRuntime(586):  at com.example.ridehistory.RideHistoryAdapter.getView(RideHistoryAdapter.java:52)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.HeaderViewListAdapter.getView(HeaderViewListAdapter.java:220)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.AbsListView.obtainView(AbsListView.java:1315)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.ListView.makeAndAddView(ListView.java:1727)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.ListView.fillDown(ListView.java:652)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.ListView.fillFromTop(ListView.java:709)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.ListView.layoutChildren(ListView.java:1580)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.AbsListView.onLayout(AbsListView.java:1147)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.view.View.layout(View.java:7035)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.RelativeLayout.onLayout(RelativeLayout.java:909)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.view.View.layout(View.java:7035)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.view.View.layout(View.java:7035)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1249)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1125)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.LinearLayout.onLayout(LinearLayout.java:1042)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.view.View.layout(View.java:7035)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.view.View.layout(View.java:7035)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.view.ViewRoot.performTraversals(ViewRoot.java:1045)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.view.ViewRoot.handleMessage(ViewRoot.java:1727)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.os.Handler.dispatchMessage(Handler.java:99)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.os.Looper.loop(Looper.java:123)
05-03 04:13:50.937: E/AndroidRuntime(586):  at android.app.ActivityThread.main(ActivityThread.java:4627)
05-03 04:13:50.937: E/AndroidRuntime(586):  at java.lang.reflect.Method.invokeNative(Native Method)
05-03 04:13:50.937: E/AndroidRuntime(586):  at java.lang.reflect.Method.invoke(Method.java:521)
05-03 04:13:50.937: E/AndroidRuntime(586):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-03 04:13:50.937: E/AndroidRuntime(586):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-03 04:13:50.937: E/AndroidRuntime(586):  at dalvik.system.NativeStart.main(Native Method)
05-03 04:18:50.997: I/Process(586): Sending signal. PID: 586 SIG: 9
05-03 04:35:30.760: D/AndroidRuntime(616): Shutting down VM
05-03 04:35:30.760: W/dalvikvm(616): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
05-03 04:35:30.779: E/AndroidRuntime(616): FATAL EXCEPTION: main
05-03 04:35:30.779: E/AndroidRuntime(616): java.lang.NullPointerException
05-03 04:35:30.779: E/AndroidRuntime(616):  at com.example.ridehistory.RideHistoryAdapter.getView(RideHistoryAdapter.java:55)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.HeaderViewListAdapter.getView(HeaderViewListAdapter.java:220)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.AbsListView.obtainView(AbsListView.java:1315)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.ListView.makeAndAddView(ListView.java:1727)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.ListView.fillDown(ListView.java:652)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.ListView.fillFromTop(ListView.java:709)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.ListView.layoutChildren(ListView.java:1580)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.AbsListView.onLayout(AbsListView.java:1147)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.view.View.layout(View.java:7035)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.RelativeLayout.onLayout(RelativeLayout.java:909)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.view.View.layout(View.java:7035)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.view.View.layout(View.java:7035)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1249)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1125)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.LinearLayout.onLayout(LinearLayout.java:1042)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.view.View.layout(View.java:7035)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.view.View.layout(View.java:7035)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.view.ViewRoot.performTraversals(ViewRoot.java:1045)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.view.ViewRoot.handleMessage(ViewRoot.java:1727)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.os.Handler.dispatchMessage(Handler.java:99)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.os.Looper.loop(Looper.java:123)
05-03 04:35:30.779: E/AndroidRuntime(616):  at android.app.ActivityThread.main(ActivityThread.java:4627)
05-03 04:35:30.779: E/AndroidRuntime(616):  at java.lang.reflect.Method.invokeNative(Native Method)
05-03 04:35:30.779: E/AndroidRuntime(616):  at java.lang.reflect.Method.invoke(Method.java:521)
05-03 04:35:30.779: E/AndroidRuntime(616):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-03 04:35:30.779: E/AndroidRuntime(616):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-03 04:35:30.779: E/AndroidRuntime(616):  at dalvik.system.NativeStart.main(Native Method)
05-03 04:35:35.667: I/Process(616): Sending signal. PID: 616 SIG: 9
05-03 04:37:52.767: D/AndroidRuntime(646): Shutting down VM
05-03 04:37:52.777: W/dalvikvm(646): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
05-03 04:37:52.787: E/AndroidRuntime(646): FATAL EXCEPTION: main
05-03 04:37:52.787: E/AndroidRuntime(646): java.lang.NullPointerException
05-03 04:37:52.787: E/AndroidRuntime(646):  at com.example.ridehistory.RideHistoryAdapter.getView(RideHistoryAdapter.java:55)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.HeaderViewListAdapter.getView(HeaderViewListAdapter.java:220)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.AbsListView.obtainView(AbsListView.java:1315)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.ListView.makeAndAddView(ListView.java:1727)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.ListView.fillDown(ListView.java:652)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.ListView.fillFromTop(ListView.java:709)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.ListView.layoutChildren(ListView.java:1580)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.AbsListView.onLayout(AbsListView.java:1147)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.view.View.layout(View.java:7035)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.RelativeLayout.onLayout(RelativeLayout.java:909)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.view.View.layout(View.java:7035)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.view.View.layout(View.java:7035)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1249)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1125)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.LinearLayout.onLayout(LinearLayout.java:1042)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.view.View.layout(View.java:7035)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.view.View.layout(View.java:7035)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.view.ViewRoot.performTraversals(ViewRoot.java:1045)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.view.ViewRoot.handleMessage(ViewRoot.java:1727)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.os.Handler.dispatchMessage(Handler.java:99)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.os.Looper.loop(Looper.java:123)
05-03 04:37:52.787: E/AndroidRuntime(646):  at android.app.ActivityThread.main(ActivityThread.java:4627)
05-03 04:37:52.787: E/AndroidRuntime(646):  at java.lang.reflect.Method.invokeNative(Native Method)
05-03 04:37:52.787: E/AndroidRuntime(646):  at java.lang.reflect.Method.invoke(Method.java:521)
05-03 04:37:52.787: E/AndroidRuntime(646):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-03 04:37:52.787: E/AndroidRuntime(646):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-03 04:37:52.787: E/AndroidRuntime(646):  at dalvik.system.NativeStart.main(Native Method)
05-03 04:37:56.817: I/Process(646): Sending signal. PID: 646 SIG: 9
05-03 04:39:41.727: D/AndroidRuntime(675): Shutting down VM
05-03 04:39:41.727: W/dalvikvm(675): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
05-03 04:39:41.761: E/AndroidRuntime(675): FATAL EXCEPTION: main
05-03 04:39:41.761: E/AndroidRuntime(675): java.lang.NullPointerException
05-03 04:39:41.761: E/AndroidRuntime(675):  at com.example.ridehistory.RideHistoryAdapter.getView(RideHistoryAdapter.java:55)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.HeaderViewListAdapter.getView(HeaderViewListAdapter.java:220)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.AbsListView.obtainView(AbsListView.java:1315)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.ListView.makeAndAddView(ListView.java:1727)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.ListView.fillDown(ListView.java:652)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.ListView.fillFromTop(ListView.java:709)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.ListView.layoutChildren(ListView.java:1580)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.AbsListView.onLayout(AbsListView.java:1147)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.view.View.layout(View.java:7035)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.RelativeLayout.onLayout(RelativeLayout.java:909)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.view.View.layout(View.java:7035)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.view.View.layout(View.java:7035)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1249)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1125)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.LinearLayout.onLayout(LinearLayout.java:1042)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.view.View.layout(View.java:7035)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.view.View.layout(View.java:7035)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.view.ViewRoot.performTraversals(ViewRoot.java:1045)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.view.ViewRoot.handleMessage(ViewRoot.java:1727)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.os.Handler.dispatchMessage(Handler.java:99)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.os.Looper.loop(Looper.java:123)
05-03 04:39:41.761: E/AndroidRuntime(675):  at android.app.ActivityThread.main(ActivityThread.java:4627)
05-03 04:39:41.761: E/AndroidRuntime(675):  at java.lang.reflect.Method.invokeNative(Native Method)
05-03 04:39:41.761: E/AndroidRuntime(675):  at java.lang.reflect.Method.invoke(Method.java:521)
05-03 04:39:41.761: E/AndroidRuntime(675):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
05-03 04:39:41.761: E/AndroidRuntime(675):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
05-03 04:39:41.761: E/AndroidRuntime(675):  at dalvik.system.NativeStart.main(Native Method)
05-03 04:39:46.888: I/Process(675): Sending signal. PID: 675 SIG: 9
05-03 04:58:52.298: D/AndroidRuntime(704): Shutting down VM
05-03 04:58:52.298: W/dalvikvm(704): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
05-03 04:58:52.318: E/AndroidRuntime(704): FATAL EXCEPTION: main
05-03 04:58:52.318: E/AndroidRuntime(704): java.lang.NullPointerException
05-03 04:58:52.318: E/AndroidRuntime(704):  at com.example.ridehistory.RideHistoryAdapter.getView(RideHistoryAdapter.java:55)
05-03 04:58:52.318: E/AndroidRuntime(704):  at android.widget.HeaderViewListAdapter.getView(HeaderViewListAdapter.java:220)
4

2 回答 2

4

NullPointerException发生在该行,holder.txtDateTime.setText(rideTransaction.dateTime.toString());因为您尚未初始化holder.txtDateTime

使用前初始化ie,添加这一行

holder.txtDateTime = (TextView)row.findViewById(R.id.txtDateTime);

于 2013-05-03T05:19:55.737 回答
2

我认为在初始化你的视图时你忘记了

holder.txtDateTime

所以这是空的

holder.txtDateTime.setText(rideTransaction.dateTime.toString());

失败。

此外,如果您发布 Stacktrace 以指示代码中的行,这将有所帮助,这样其他人就不必进行行数计数。例如

holder.txtDateTime.setText(rideTransaction.dateTime.toString()); // <-- NullPointerException here!

它也可能导致您自己发现错误。

于 2013-05-03T05:22:08.923 回答