We need to inflate a listview in 2 cases.
1. When we want to display a listview at run time
2. When we need a custom listview
We will see both the cases with examples.
Case 1: In this example we will inflate a listview. See how
Android Layout File
File: res/layout/main.xml
File: res/layout/activity_main.xml
The same thing we can do without inflating in a simple way by including listview in our main.xml and adding
final ListView listview = (ListView) findViewById(R.id.listview);
instead of
final LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
ListView t = (ListView)inflater.inflate(R.layout.activity_main,null);
ILayout = (LinearLayout)findViewById(R.id.layout1);
ILayout.addView(t);
Case 2: We will create a custom listview having a image & text in it. To create a custom listview,we need to create custom adapter. In this example we will use arrayadapter for easy understanding. You will need 2 layout files. One, main.xml, will define the attributes of the ListView. The other, mainlvitem.xml, will be the layout of each individual row in the ListView.
File: res/layout/main.xml:
We have used default images which comes with drawable folder ic_launcher in this program.However you can use any other image as you want. You need to put those images in appropriate folder.
1. When we want to display a listview at run time
2. When we need a custom listview
We will see both the cases with examples.
Case 1: In this example we will inflate a listview. See how
Android Layout File
File: res/layout/main.xml
<linearlayout android:id="@+id/layout1" android:layout_height="match_parent" android:layout_width="match_parent" android:orientation="vertical" xmlns:android="http://schemas.android.com/apk/res/android"> <textview android:id="@+id/namelabel" android:layout_height="wrap_content" android:layout_width="wrap_content" android:text="Text Paragraph."> </textview> </linearlayout>We have another layout file activity_main having listview in it.
File: res/layout/activity_main.xml
<ListView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/listview" android:layout_width="fill_parent" android:layout_height="fill_parent" android:cacheColorHint="#EEEEEE" android:background="#CCCCCC" />We are going to inflate layout activity_main in our main activity.Our main inflatelistview activity is as follows.
package com.example.inflatelistview;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.Menu;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.TextView;
public class inflatelistview extends Activity {
LinearLayout ILayout;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
final LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
ListView t = (ListView)inflater.inflate(R.layout.activity_main,null);
ILayout = (LinearLayout)findViewById(R.id.layout1);
ILayout.addView(t);
String[] values = new String[] { "Item1","Item2","Item3","Item4"};
final ArrayList list = new ArrayList();
for (int i = 0; i < values.length; ++i) {
list.add(values[i]);
}
final OurArrayAdapter adapter = new OurArrayAdapter(this,
android.R.layout.simple_list_item_1, list);
t.setAdapter(adapter);
}
private class OurArrayAdapter extends ArrayAdapter {
HashMap MapValue = new HashMap();
public OurArrayAdapter(Context context, int textViewResourceId,
List objects) {
super(context, textViewResourceId, objects);
for (int i = 0; i < objects.size(); ++i) {
MapValue.put(objects.get(i), i);
}
}
@Override
public long getItemId(int position) {
String item = getItem(position);
return MapValue.get(item);
}
@Override
public boolean hasStableIds() {
return true;
}
}
}
The same thing we can do without inflating in a simple way by including listview in our main.xml and adding
final ListView listview = (ListView) findViewById(R.id.listview);
instead of
final LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
ListView t = (ListView)inflater.inflate(R.layout.activity_main,null);
ILayout = (LinearLayout)findViewById(R.id.layout1);
ILayout.addView(t);
Case 2: We will create a custom listview having a image & text in it. To create a custom listview,we need to create custom adapter. In this example we will use arrayadapter for easy understanding. You will need 2 layout files. One, main.xml, will define the attributes of the ListView. The other, mainlvitem.xml, will be the layout of each individual row in the ListView.
File: res/layout/main.xml:
<ListView xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/listview" android:layout_width="fill_parent" android:layout_height="fill_parent" android:cacheColorHint="#EEEEEE" android:background="#CCCCCC" />Next File,res/layout/mainlvitem.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="horizontal" android:paddingLeft="4dp" android:paddingRight="15dp" android:paddingTop="13dp" android:paddingBottom="13dp" android:weightSum="1" android:background="#FFFFFF" > <ImageView android:id="@+id/img" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center_vertical" android:layout_weight="0.10" /> <TextView android:id="@+id/txt" android:layout_width="0dp" android:layout_height="wrap_content" android:layout_gravity="center" android:gravity="left" android:layout_weight="0.90" android:paddingLeft="10dp" android:textColor="#222222"/> </LinearLayout>Now the main activity is
package com.example.inflatelistview;
import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
public class customlistview extends Activity {
// We will declare some variables within the class, but outside of any method so that
// any method can use them.
ListView lv; // The ListView we will be building
// A String[] array that will hold the names of the items.
String[] mItems = { "Item1", "Item2", "Item3" };
// An Integer[] array that will hold the resource drawables that will be displayed as icons.
Integer[] mIcons =
{ R.drawable.ic_launcher, R.drawable.ic_launcher, R.drawable.ic_launcher };
// -----------------------------------------------
// onCreate()
// -----------------------------------------------
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Here we will take the ListView that we declared in activity_main layout
lv = (ListView) findViewById(R.id.listview);
// Instead of using a regular ArrayAdapter to pull Strings from an array,
// we will create a custom ArrayAdapter below. This bit of code sets the adapter
// of our ListView, lv, to our customer adapter.
ArrayAdapter adapter = new CustomAdapter(this, R.layout.mainlvitem, mItems);
lv.setAdapter(adapter);
} // end onCreate
// -----------------------------------------------
// This is our custom ArrayAdapter, CustomAdapter
// -----------------------------------------------
public class CustomAdapter extends ArrayAdapter
{
public CustomAdapter(Context context, int textViewResourceId, String[] objects)
{
super(context, textViewResourceId, objects);
}
@Override
public View getView(int position, View convertView, ViewGroup parent)
{
// Inflate the layout, mainlvitem.xml, in each row.
LayoutInflater inflater = customlistview.this.getLayoutInflater();
View row = inflater.inflate(R.layout.mainlvitem, parent, false);
// Declare and define the TextView, "item." This is where
// the name of each item will appear.
TextView item = (TextView)row.findViewById(R.id.txt);
item.setText(mItems[position]);
// Declare and define the TextView, "icon." This is where
// the icon in each row will appear.
ImageView icon=(ImageView)row.findViewById(R.id.img);
icon.setImageResource(mIcons[position]);
return row;
}
} // end CustomAdapter
}
We have used default images which comes with drawable folder ic_launcher in this program.However you can use any other image as you want. You need to put those images in appropriate folder.
