Oto listingi:
MainAcivity.java
package com.example.polmedia;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.RadioGroup.OnCheckedChangeListener;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends Activity implements OnCheckedChangeListener{
ArrayList<ChannelData> list = new ArrayList<ChannelData>();
public void onListItemClick(ListView parent, View v, int position, long id){
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
((RadioGroup)findViewById(R.id.radioGroup1)).setOnCheckedChangeListener((OnCheckedChangeListener) this);
RadioButton S1 = (RadioButton) findViewById(R.id.S1);
S1.setChecked(true);
////////////////////////////////////////
ChannelsList tmp = new ChannelsList();
try {
list = tmp.getChannelsList("server1");
} catch (IOException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
Collections.sort(list);
//////////////////////////////////////////////////
ArrayAdapter<ChannelData> adapter = new ArrayAdapter<ChannelData>(getApplicationContext(),
android.R.layout.test_list_item, list) {
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = super.getView(position, convertView, parent);
ChannelData currentChannel = getItem(position);
// Inflate only once
if(convertView == null) {
convertView = getLayoutInflater()
.inflate(R.layout.custom_item,
null, false);
}
ViewHolder viewHolder = new ViewHolder();
viewHolder.ChannelName =
(TextView)convertView.findViewById(R.id.channel_name);
convertView.setTag(viewHolder);
TextView text =
((ViewHolder)convertView.getTag()).ChannelName;
text.setText(currentChannel.getAName());
text.setTextColor(Color.WHITE);
return view;
}
};
// Lista.
ListView lv = (ListView) findViewById(R.id.listView1);
// Powiązanie ListView z adapterem.
lv.setAdapter(adapter);
}
static class ViewHolder{
TextView ChannelName;
}
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
String groupName ="";
groupName+="Fancy radio group: ";
RadioButton rb = (RadioButton) findViewById(checkedId);
Toast.makeText(this, groupName+rb.getText(), Toast.LENGTH_LONG).show();
}
}
custom_item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="@dimen/activity_horizontal_margin">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Large Text"
android:id="@+id/channel_name" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:text="Small Text"
android:id="@+id/channel_url" />
</LinearLayout>
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity" >
<RadioGroup
android:id="@+id/radioGroup1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#080000"
android:orientation="horizontal" >
<RadioButton
android:id="@+id/S1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:layout_weight=".335"
android:background="@drawable/radio_states_red"
android:button="@null"
android:checked="false"
android:gravity="center"
android:padding="10dp"
android:text="S1"
android:textColor="@drawable/radio_text" />
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/radio_states_red"
android:button="@null"
android:padding="10dp"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:textColor="@drawable/radio_text"
android:text="S2"
android:layout_weight=".335"
android:gravity="center"/>
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/radio_states_red"
android:button="@null"
android:padding="10dp"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:textColor="@drawable/radio_text"
android:text="S3"
android:layout_weight=".335"
android:gravity="center"/>
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/radio_states_red"
android:button="@null"
android:padding="10dp"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:textColor="@drawable/radio_text"
android:text="S4"
android:layout_weight=".335"
android:gravity="center"/>
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/radio_states_red"
android:button="@null"
android:padding="10dp"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
android:textColor="@drawable/radio_text"
android:text="S5"
android:layout_weight=".335"
android:gravity="center"/>
</RadioGroup>
<ListView
android:id="@+id/listView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:background="@drawable/listview_border"
android:clickable="true"
android:fitsSystemWindows="true"
android:layoutMode="opticalBounds"
android:padding="25dp"
android:textColor="#A0E0ED"
android:textSize="17sp"
android:textStyle="bold" >
</ListView>
</LinearLayout>
i logi:
08-17 17:57:31.780: D/AndroidRuntime(802): Shutting down VM
08-17 17:57:31.780: W/dalvikvm(802): threadid=1: thread exiting with uncaught exception (group=0xb4af0ba8)
08-17 17:57:31.860: E/AndroidRuntime(802): FATAL EXCEPTION: main
08-17 17:57:31.860: E/AndroidRuntime(802): Process: com.example.polmedia, PID: 802
08-17 17:57:31.860: E/AndroidRuntime(802): java.lang.NullPointerException
08-17 17:57:31.860: E/AndroidRuntime(802): at com.example.polmedia.MainActivity$1.getView(MainActivity.java:87)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.widget.AbsListView.obtainView(AbsListView.java:2240)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.widget.ListView.measureHeightOfChildren(ListView.java:1263)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.widget.ListView.onMeasure(ListView.java:1175)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.View.measure(View.java:16497)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.View.measure(View.java:16497)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.View.measure(View.java:16497)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
08-17 17:57:31.860: E/AndroidRuntime(802): at com.android.internal.widget.ActionBarOverlayLayout.onMeasure(ActionBarOverlayLayout.java:327)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.View.measure(View.java:16497)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5125)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
08-17 17:57:31.860: E/AndroidRuntime(802): at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2291)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.View.measure(View.java:16497)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1916)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1113)
08-17 17:57:31.860: E/AndroidRuntime(802): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1295)
Jak widać w pewnym momencie następuje wyjątek NullPointException. Jak to mogę naprawić i jaka jest przyczyna? Dodam, że program piszę w Eclipse.