好的,我正在尝试填充列表视图,但在加载时它正在崩溃。
将产品从CSV导入Android Studio中的列表视图。
这是我的CSV https://drive.google.com/file/d/0BycsF7WMf1cYMzBOMk1mZmliWW8/view?usp=sharing
MainActivity:
import android.app.Activity;
import android.os.Bundle;
import android.widget.ListView;
public class MainActivity extends Activity {
ListViewAdapter itemAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ListView itemList = (ListView)findViewById(R.id.itemListView);
itemAdapter = new ListViewAdapter(this, -1);
itemList.setAdapter(itemAdapter);
}
}
ListViewAdapter
import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.TextView;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
public class ListViewAdapter extends ArrayAdapter<DataStates> {
Context contxt;
public ListViewAdapter(Context context, int testViewResourceID) {
super(context, testViewResourceID);
contxt = context;
loadArrayData();
}
@Override
public View getView (final int pos, View convertView, final ViewGroup parent) {
TextView mView = (TextView) convertView;
if(mView == null) {
mView = new TextView(parent.getContext());
mView.setTextSize(28);
}
return mView;
}
private void loadArrayData() {
try {
InputStream is = contxt.getAssets().open("data.csv");
BufferedReader reader = new BufferedReader(new InputStreamReader(is));
String line;
while ((line = reader.readLine()) != null) {
String[] RowData = line.split(",");
DataStates cur = new DataStates();
cur.setTitle(RowData[2]);
cur.setPrice(RowData[3]);
cur.setDescription(RowData[4]);
this.add(cur);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
DataStates
import android.net.Uri;
public class DataStates {
private String title;
private String price;
private String description;
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getPrice() {
return price;
}
public void setPrice(String price) {
this.price = price;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
}
activity_main
<LinearLayout
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:orientation="vertical">
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/itemListView"
android:layout_alignParentBottom="true"
android:layout_alignParentEnd="true"
android:layout_alignParentStart="true" />
</LinearLayout>
LogCat信息
10-07 21:43:31.241 25819-25819/tk.delacour.projectalpha D/dalvikvm﹕ Late-enabling CheckJNI
10-07 21:43:31.241 25819-25819/tk.delacour.projectalpha D/dalvikvm﹕ Try to disable coredump for pid 25819
10-07 21:43:31.241 25819-25819/tk.delacour.projectalpha D/dalvikvm﹕ Process 25819 nice name: tk.delacour.projectalpha
10-07 21:43:31.241 25819-25819/tk.delacour.projectalpha D/dalvikvm﹕ Extra Options: not specified
10-07 21:43:31.401 25819-25819/tk.delacour.projectalpha D/AndroidRuntime﹕ Shutting down VM
10-07 21:43:31.401 25819-25819/tk.delacour.projectalpha W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x42f05500)
10-07 21:43:31.411 25819-25819/tk.delacour.projectalpha E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{tk.delacour.projectalpha/tk.delacour.projectalpha.MainActivity}: java.lang.ArrayIndexOutOfBoundsException: length=4; index=4
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2342)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417)
at android.app.ActivityThread.access$600(ActivityThread.java:148)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1355)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:150)
at android.app.ActivityThread.main(ActivityThread.java:5390)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.ArrayIndexOutOfBoundsException: length=4; index=4
at tk.delacour.projectalpha.ListViewAdapter.loadArrayData(ListViewAdapter.java:63)
at tk.delacour.projectalpha.ListViewAdapter.<init>(ListViewAdapter.java:28)
at tk.delacour.projectalpha.MainActivity.onCreate(MainActivity.java:19)
at android.app.Activity.performCreate(Activity.java:5303)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2296)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2417)
at android.app.ActivityThread.access$600(ActivityThread.java:148)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1355)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:150)
at android.app.ActivityThread.main(ActivityThread.java:5390)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
答案 0 :(得分:0)
索引从0开始,所以
cur.setDescription(RowData[4]);
将导致NPE,因为在您的CSV中,您只有4列(索引为0,1,2,3)。
您的案例中的描述是3
答案 1 :(得分:0)
好的,你的程序在这一点上失败了:
while ((line = reader.readLine()) != null) {
String[] RowData = line.split(",");
DataStates cur = new DataStates();
cur.setTitle(RowData[2]);
cur.setPrice(RowData[3]);
// now there is a ArrayIndexOutOfBoundsException
cur.setDescription(RowData[4]);
this.add(cur);
}
索引从0开始,所以我认为正确的代码是
while ((line = reader.readLine()) != null) {
String[] RowData = line.split(",");
if(RowData.length <4)
continue;
DataStates cur = new DataStates();
cur.setTitle(RowData[1]);
cur.setPrice(RowData[2]);
cur.setDescription(RowData[3]);
this.add(cur);
}
答案 2 :(得分:0)
您需要替换
cur.setTitle(RowData[2]);
cur.setPrice(RowData[3]);
cur.setDescription(RowData[4]);
与
cur.setTitle(RowData[1]);
cur.setPrice(RowData[2]);
cur.setDescription(RowData[3]);
您在RowData中只有4个值,并且您正尝试访问第5个值。
Caused by: java.lang.ArrayIndexOutOfBoundsException: length=4; index=4
您需要考虑索引0到3.不是1到4。
希望这有帮助。