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Android, How to split ListView elements into three parts?

In my activity, I have three lists, and each list consists of three elements. After testing this method (see below: Android, how to add a ScrollView to a screen with some list items? ), I found that it is not possible to scroll the screen while you have lists in action. In addition, I found this answer ( add several lists to one activity ), which divided the screen into three segments, so I did not have enough space to show all the elements and the screen also did not scroll.

one stupid solution is to create xml for each element and put it in the xml location of the activity. Although it works, but I need to copy / paste as many lines of code.

It’s better to use an adapter, so in my next attempt I can add the result from two other lists to my first list and then send the result to the adapter class. Therefore, the adapter will display all the items in the list. Although, it solves my problem when scrolling the screen (at this time scrolling the screen = scrolling the list), but I need to have a title on top of each of the three elements.

Is it possible to tell the adapter to add, for example, header.xml, after each three elements of the list?

Hope to explain clearly! Thanks

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main.xml

<?xml version="1.0" encoding="utf-8"?>
<ListView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@android:id/list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:drawSelectorOnTop="true"
/>

header.xml

<TextView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center" android:scrollbars="none"
style="?android:attr/listSeparatorTextViewStyle" />

Now java file code is below.

SectionedAdapter.java

package com.android.listview;

import android.view.View;
import android.view.ViewGroup;
import android.widget.Adapter;
import android.widget.BaseAdapter;
import java.util.ArrayList;
import java.util.List;

abstract public class SectionedAdapter extends BaseAdapter {
abstract protected View getHeaderView(String caption, int index,
View convertView, ViewGroup parent);

private List
sections = new ArrayList
();
private static int TYPE_SECTION_HEADER = 1;

public SectionedAdapter() {
super();
}

public void addSection(String caption, Adapter adapter) {
sections.add(new Section(caption, adapter));
}

public Object getItem(int position) {
for (Section section : this.sections) {
if (position == 0) {
return (section);
}

int size = section.adapter.getCount() + 1;

if (position <>
return (section.adapter.getItem(position - 1));
}

position -= size;
}

return (null);
}

public int getCount() {
int total = 0;

for (Section section : this.sections) {
total += section.adapter.getCount() + 1; // add one for header
}

return (total);
}

public int getViewTypeCount() {
int total = 1; // one for the header, plus those from sections

for (Section section : this.sections) {
total += section.adapter.getViewTypeCount();
}

return (total);
}

public int getItemViewType(int position) {
int typeOffset = TYPE_SECTION_HEADER + 1; // start counting from here

for (Section section : this.sections) {
if (position == 0) {
return (TYPE_SECTION_HEADER);
}

int size = section.adapter.getCount() + 1;

if (position <>
return (typeOffset + section.adapter
.getItemViewType(position - 1));
}

position -= size;
typeOffset += section.adapter.getViewTypeCount();
}

return (-1);
}

public boolean areAllItemsSelectable() {
return (false);
}

public boolean isEnabled(int position) {
return (getItemViewType(position) != TYPE_SECTION_HEADER);
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
int sectionIndex = 0;

for (Section section : this.sections) {
if (position == 0) {
return (getHeaderView(section.caption, sectionIndex,
convertView, parent));
}

int size = section.adapter.getCount() + 1;

if (position <>
return (section.adapter.getView(position - 1, convertView,
parent));
}

position -= size;
sectionIndex++;
}

return (null);
}

@Override
public long getItemId(int position) {
return (position);
}

class Section {
String caption;
Adapter adapter;

Section(String caption, Adapter adapter) {
this.caption = caption;
this.adapter = adapter;
}
}
}

Selection.java

package com.commonsware.android.listview;

import android.app.ListActivity;
import android.content.Context;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

public class SectionedDemo extends ListActivity {
private static String[] items = { "US", "UK", "CANADA", "JAPAN", "SINGAPORE",
"INDIA", "CHINA" };

private static String[] Sect = { "GOOGLE", "FACEBOOK","DELL" };

private static String[] Doc = { "FRONT", "TOP","BACK" };

@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.main);

adapter.addSection("step 1", new ArrayAdapter(this,
android.R.layout.simple_list_item_1, items));

adapter.addSection("Step 2", new ArrayAdapter(this,
android.R.layout.simple_list_item_1, Sect));

adapter.addSection("Step 3", new ArrayAdapter(this,
android.R.layout.simple_list_item_1, Doc));

setListAdapter(adapter);
}

SectionedAdapter adapter = new SectionedAdapter() {
protected View getHeaderView(String caption, int index,
View convertView, ViewGroup parent) {
TextView result = (TextView) convertView;

if (convertView == null) {
result = (TextView) getLayoutInflater().inflate(
R.layout.header, null);
}

result.setText(caption);

return (result);
}
};
}

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