Saturday, 29 September 2012

Android Multiple Select ListView



Android Multiple Choice ListView Using Custom Adapter.This listview you can use when you send sms to more than one friend or any notification to your friends.


So using Custom Adapeter we have to create row.xml layout which has checkbox.

row.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:background="@android:color/white" >

    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_centerVertical="true"
        android:layout_margin="5dp"
        android:layout_toLeftOf="@+id/checkbox"
        android:text="title"
        android:textColor="@android:color/black"
        android:textSize="20dp"
        android:textStyle="bold" >
    </TextView>

    <CheckBox
        android:id="@+id/checkbox"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_centerVertical="true"
        android:layout_marginRight="10dip"
        android:background="@drawable/chk"
        android:button="@null"
        android:focusable="false"
        android:focusableInTouchMode="false" >
    </CheckBox>
</RelativeLayout>

 Now Using Adapter we can bind data to ListView.But we need to learn easy way to bind data with custom ListView and also hadle CheckBox Listener For Each Row.

So here i have RSS Feed to get data from web and then i add it in List<NameBean>.NameBean is bean class which contains value of Rss Feed Element and we have to maintain one boolean for checkbox state either checked or not.And generate Getters And Setters.

NameBean.java


public class NameBean {

private String name;
private boolean selected;

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public boolean isSelected() {
return selected;
}

public void setSelected(boolean selected) {
this.selected = selected;
}

}

Now when you get data through XML Parsing you have to create Object of NameBean and you can set data and add Object to List.


for (int temp = 0; temp < nList.getLength(); temp++) {

Node nNode = nList.item(temp);

                  if (nNode.getNodeType() == Node.ELEMENT_NODE) {

   Element eElement = (Element) nNode;

    NameBean objItem = new NameBean();

   objItem.setName(getTagValue("name", eElement));
                 
   list.add(objItem);

}
}



Now list  is fill up with NameBean Objects.And you can retrive data in Adapter so when you set ListView you just retrieve data in getView(...) method of Adapter.

In getView(...) method put checkBox listener to listen checkbox is check or not, if its checked then set boolean true for that object of NameBean And if its not checked then setSelected false to Namebean object.

So when you start this example in listview and its get data from webservice and bind data to listview using NameAdapter Class.



NameAdapter.java


import java.util.List;

import android.app.Activity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.TextView;

public class NamesAdapter extends ArrayAdapter<NameBean> {

private List<NameBean> list;
private LayoutInflater inflator;

public NamesAdapter(Activity context, List<NameBean> list) {
super(context, R.layout.row, list);
this.list = list;
inflator = context.getLayoutInflater();
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

ViewHolder holder = null;
if (convertView == null) {
convertView = inflator.inflate(R.layout.row, null);
holder = new ViewHolder();
holder.title = (TextView) convertView.findViewById(R.id.title);
holder.chk = (CheckBox) convertView.findViewById(R.id.checkbox);
holder.chk
.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {

@Override
public void onCheckedChanged(CompoundButton view,
boolean isChecked) {
int getPosition = (Integer) view.getTag();
list.get(getPosition).setSelected(view.isChecked());

}
});
convertView.setTag(holder);
convertView.setTag(R.id.title, holder.title);
convertView.setTag(R.id.checkbox, holder.chk);
} else {
holder = (ViewHolder) convertView.getTag();
}
holder.chk.setTag(position);

holder.title.setText(list.get(position).getName());
holder.chk.setChecked(list.get(position).isSelected());

return convertView;
}

static class ViewHolder {
protected TextView title;
protected CheckBox chk;
}
}


When your listView is bind with data you can see checkbox in row with name and now you can get Selected name using NameBean Object and you can retrieve it from list.


                // Retrive Data from list Using for-each loop
                StringBuffer sb = new StringBuffer();
for (NameBean bean : items) {

if (bean.isSelected()) {
sb.append(bean.getName());
sb.append(",");
}
}



Now you get All Selected name from ListView.So its so easy to write Multiple Choice ListView in Android.


You Can Download Full Source Code

Wednesday, 26 September 2012

Android Populate Spinner From Sqlite Database



















Android Spinner is DropDown Choice List in Android.You can pick up one item and make your choice from list.

When you get Data from database and display in Spinner, So first you have to create database to get data from database and save it in Dynamic Array.

So first Create DataBaseHelper.java that create database and add data in database.


package com.samir.spinner;

import java.util.HashSet;
import java.util.Set;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

public class DatabaseHelper extends SQLiteOpenHelper {
private static final int DB_VERSION = 1;
private static final String DB_NAME = "mydb";
private static final String TABLE_NAME = "mytable";
private static final String _id = "_id";
private static final String name = "name";

public DatabaseHelper(Context context) {
super(context, DB_NAME, null, DB_VERSION);
}

@Override
public void onCreate(SQLiteDatabase db) {
String createTableQuery = "create table " + TABLE_NAME + "(" + _id+ "     INTEGER PRIMARY KEY," + name + " TEXT)";
db.execSQL(createTableQuery);
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)  

        {
db.execSQL("drop table if exists " + TABLE_NAME);
onCreate(db);
}

public void insertData(String label) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(name, label);
db.insert(TABLE_NAME, null, values);
db.close();
}

public Set<String> getAllData() {
Set<String> set = new HashSet<String>();
String selectQuery = "select * from " + TABLE_NAME;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
if (cursor.moveToFirst()) {
do {
set.add(cursor.getString(1));
} while (cursor.moveToNext());
}
cursor.close();
db.close();
return set;
}
}


Now you can see Oncreate Method is Create Database and using query you can create database.Database have two column one in _id which is primary key and second is name which we  want to save in database.

Then Using  ContentValue you can insert Data in database see method insertData(String lable) in above class.

Now, To get All data from database you just fire query and its return Cursor.Then put data in dynamic array from cursor.See method  getAllData().

Here i used Set<String> as dynamic array Because Set doesnot allow duplicates.And Spinner only show unique name.

Once you get Set then you can easily convert it in List<String>.Then you can easily append data to spinner using ArrayAdapter.


       Set<String> set = db.getAllData();
       //Convert set into list
  List<String> list = new ArrayList<String>(set);
  //Sort Data Alphabetical order
  Collections.sort(list, new Comparator<String>() {
@Override
public int compare(String lhs, String rhs) {
return lhs.compareTo(rhs);
}
  });
  adapter = new ArrayAdapter<String>(MainActivity.this,
android.R.layout.simple_spinner_item, list);
  adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
  spinner.setAdapter(adapter);


Now spinner have listener to listen selected item .
 

spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
@Override
public void onItemSelected(AdapterView<?> parent, View v, int position,long id) {
     String name = parent.getItemAtPosition(position).toString();
showToast("You Selected Item :: " + name);
       }
@Override
public void onNothingSelected(AdapterView<?> arg0) {
}
    }); 



Download Full Source Code::

You Can Download Full Source Code