Lowyat.NET: Latest topics by Shouba

Android expandableListView using JSON stuck!

Shouba — Sat, 16 Nov 2013 16:07:52 +0800

I am trying to get data from my database and show it in an Expandable list view.
The application keeps on crashing but the data is successfully retrieved from the database

My adapter for the expandable list

CODE

package com.example.monoprix;

import java.util.List;
import java.util.Map;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.graphics.Typeface;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.BaseExpandableListAdapter;
import android.widget.ImageView;
import android.widget.TextView;

public class ExpandableListAdapterA extends BaseExpandableListAdapter {

private Activity context;
private Map<String, List<String>> laptopCollections;
private List<String> laptops;

public ExpandableListAdapterA(Activity context, List<String> laptops,
Map<String, List<String>> laptopCollections) {
this.context = context;
this.laptopCollections = laptopCollections;
this.laptops = laptops;
}

public Object getChild(int groupPosition, int childPosition) {
return laptopCollections.get(laptops.get(groupPosition)).get(childPosition);
}

public long getChildId(int groupPosition, int childPosition) {
return childPosition;
}

public View getChildView(final int groupPosition, final int childPosition,
boolean isLastChild, View convertView, ViewGroup parent) {
final String laptop = (String) getChild(groupPosition, childPosition);
LayoutInflater inflater = context.getLayoutInflater();

if (convertView == null) {
convertView = inflater.inflate(R.layout.child_view, null);
}

TextView item = (TextView) convertView.findViewById(R.id.laptop);

ImageView delete = (ImageView) convertView.findViewById(R.id.delete);
delete.setOnClickListener(new OnClickListener() {

public void onClick(View v) {
AlertDialog.Builder builder = new AlertDialog.Builder(context);
builder.setMessage("Do you want to remove?");
builder.setCancelable(false);
builder.setPositiveButton("Yes",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
List<String> child =
laptopCollections.get(laptops.get(groupPosition));
child.remove(childPosition);
notifyDataSetChanged();
}
});
builder.setNegativeButton("No",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
dialog.cancel();
}
});
AlertDialog alertDialog = builder.create();
alertDialog.show();
}
});

item.setText(laptop);
return convertView;
}

public int getChildrenCount(int groupPosition) {
return laptopCollections.get(laptops.get(groupPosition)).size();
}

public Object getGroup(int groupPosition) {
return laptops.get(groupPosition);
}

public int getGroupCount() {
return laptops.size();
}

public long getGroupId(int groupPosition) {
return groupPosition;
}

public View getGroupView(int groupPosition, boolean isExpanded,
View convertView, ViewGroup parent) {
String laptopName = (String) getGroup(groupPosition);
if (convertView == null) {
LayoutInflater infalInflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = infalInflater.inflate(R.layout.parent_view,
null);
}
TextView item = (TextView) convertView.findViewById(R.id.head);
item.setTypeface(null, Typeface.BOLD);
item.setText(laptopName);
return convertView;
}

public boolean hasStableIds() {
return true;
}

public boolean isChildSelectable(int groupPosition, int childPosition) {
return true;
}
}

and the other class for the data

CODE

package com.example.monoprix;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.ExpandableListView.OnChildClickListener;
import android.widget.Toast;

public class Product extends Activity {

List<String> groupList;
List<String> childList;
Map<String, List<String>> laptopCollection;
ExpandableListView expListView;
private static String url = "http://10.0.2.2/Monoprix/DB_Connect.php";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.products);

new createGroupList().execute();

expListView = (ExpandableListView) findViewById(R.id.products);
final ExpandableListAdapter expListAdapter = new ExpandableListAdapterA(this, groupList, laptopCollection);
expListView.setAdapter(expListAdapter);

//setGroupIndicatorToRight();

expListView.setOnChildClickListener(new OnChildClickListener() {

public boolean onChildClick(ExpandableListView parent, View v,
int groupPosition, int childPosition, long id) {
final String selected = (String) expListAdapter.getChild(
groupPosition, childPosition);
Toast.makeText(getBaseContext(), selected, Toast.LENGTH_LONG)
.show();

return true;
}
});
}

class createGroupList extends AsyncTask<String,String,String> {
protected String doInBackground(String... args) {
groupList = new ArrayList<String>();
String[] hpModels = { "HP Pavilion G6-2014TX", "ProBook HP 4540",
"HP Envy 4-1025TX" };

//String[] lenovoModels = { "IdeaPad Z Series", "Essential G Series","ThinkPad X Series", "Ideapad Z Series" };
String[] dellModels = { "Inspiron", "Vostro", "XPS" };
try{
JSONParser jsonParser = new JSONParser();
JSONObject json = jsonParser.getJSONFromUrl(url);
Log.d("Create Response", json.toString());
JSONArray title = json.getJSONArray("product");
for (int i=0;i<title.length();i++)
{
JSONObject c = title.getJSONObject(i);
String categ = c.getString("product_category");
groupList.add(categ);
}
childList = new ArrayList<String>();
laptopCollection = new LinkedHashMap<String, List<String>>();
for (String laptop : groupList) {
if (laptop.equals("Vege")) {
for ( String model : hpModels){
childList.add(model);
}
} else if (laptop.equals("Fruits"))
{
for (String model : dellModels )
childList.add(model);
}
laptopCollection.put(laptop, childList);
}

}catch (JSONException e)
{
e.printStackTrace();
}
return null;
}
}

public int getDipsFromPixel(float pixels) {
// Get the screen's density scale
final float scale = getResources().getDisplayMetrics().density;
// Convert the dps to pixels, based on density scale
return (int) (pixels * scale + 0.5f);
}
}

Carrera Sunglasses.

Shouba — Sun, 16 Oct 2011 19:02:17 +0800

Aren't they awesome .

I wanna say that I never seen these glasses in MALAYSIA while they are popular all over the world .

Anyways can you guys help me locate a shop that sells them here .

Thanks .

Java Super class and sub class Solved . Help

Shouba — Thu, 07 Jul 2011 15:04:59 +0800

Hi , I keep getting null in my output , Why is that ?

client()

import java.util.Scanner;
public class Main{
public static void main(String args[])
{
Details d[]= new Details[5];
Scanner sc=new Scanner(System.in);
boolean ok=true;
for (int i=0;i<d.length;i++)
{
do{
try{
ok= true;
System.out.println("Enter Name :");
d[i].name=sc.nextLine();
if(d[i].name.length() == 0)
throw new Exception("\nInvalid name.Try again.");
}
catch(Exception nfe){
System.out.println(nfe.getMessage());ok=false;
}

try{
ok= true;
System.out.println("Enter BirthDay :");
d[i].birth=sc.nextLine();
if(d[i].birth.length() == 0||d[i].birth.length()>6)
throw new Exception("\nInvalid Birthday.Try again.");
}
catch(Exception nfe){
System.out.println(nfe.getMessage());ok=false;
}

try{
ok= true;
System.out.println("Enter Gender :");
d[i].gender=sc.nextLine();
if(d[i].gender.length() == 0)
throw new Exception("\nInput Gender.Try again.");
}
catch(Exception nfe){
System.out.println(nfe.getMessage());ok=false;
}

try{
ok= true;
System.out.println("Enter ID :");
d[i].id=sc.nextLine();
if(d[i].id.length() == 0)
throw new Exception("\nInput ID.Try again.");
}
catch(Exception nfe){
System.out.println(nfe.getMessage());ok=false;
}

try{
ok= true;
System.out.println("Enter Department :");
d[i].departement=sc.nextLine();
if(d[i].departement.length() == 0)
throw new Exception("\nInput Department .Try again.");
}
catch(Exception nfe){
System.out.println(nfe.getMessage());ok=false;
}

try{
ok= true;
System.out.println("Enter Department :");
d[i].departement=sc.nextLine();
if(d[i].departement.length() == 0)
throw new Exception("\nDepartment ID.Try again.");
}
catch(Exception nfe){
System.out.println(nfe.getMessage());ok=false;
}
System.out.println("Enter Department :");
d[i].departement=sc.nextLine();
System.out.println("Enter Date of Employement :");
d[i].date=sc.nextLine();
System.out.println("Enter Designation");
d[i].design=sc.nextLine();
System.out.println("Enter Salary :");
d[i].salary=sc.nextDouble();
System.out.println("Enter Allowance");
d[i].allowance=sc.nextDouble();
}}while (!ok);
}

}

Sub class

import java.util.Scanner;
public class Details extends Employee{
public double salary,allowance,net_salary,tax_ammount;
public int tax_rate;
public Details (String n,String b,String g,String i,String d,String da,String de,double s,double a,double ne,double t,int ta){
super(n,b,g,i,d,da,de);
s= salary;a= allowance;ne= net_salary;t= tax_ammount;ta=tax_rate;
}
public double getSalary(){
return salary;
}
public double getAllowance(){
return allowance;
}
public double getNet_salary(){
return net_salary;
}
public double getTax_ammount(){
return tax_ammount;
}
public double CalcNet(){
return net_salary = salary + allowance - tax_ammount;
}

}

Thanks in advance .

Need help with Do-while Loop in java .

Shouba — Sat, 04 Jun 2011 17:02:44 +0800

Why is my program not looping , thanks in advance .

public static void main (String args[])
{
char type,size,ans;
double total=0,price=0;
int op=0,num=0,quantity=0;

do
{
Scanner type1= new Scanner(System.in);
System.out.println("Please enter type of Wood ((P):for Pine,(O):for Oak or (M):for Mahogany) :");
type=type1.next().charAt(0);
Scanner size1= new Scanner(System.in);
System.out.println("Please enter size ((S):for Small,(M):for Medium,(L):for Large) :");
size=size1.next().charAt(0);
Scanner num1= new Scanner(System.in);
System.out.println("Please enter Number of Drawer :");
num=num1.nextInt();
Scanner quantity1= new Scanner(System.in);
System.out.println("Please enter Quantity :");
quantity=quantity1.nextInt();

if (type=='P'&&type=='p')
{
if (size=='S'&&size=='s')
{
price = 250;
total=(((0.25*price)*num)+price)*quantity;
}
else if (size=='M'&&size=='m')
{
price=250+(0.1*250);
total=(((0.25*price)*num)+price)*quantity;
}
else if (size=='L'&&size=='l')
{
price=250+(0.2*250);
total=(((0.25*price)*num)+price)*quantity;
}
}
else if (type=='O'&&type=='o')
{
if (size=='S'&&size=='s')
{
price=425;
total=(((0.25*price)*num)+price)*quantity;
}
else if (size=='M'&&size=='m')
{
price=425+(0.1*425);
total=(((0.25*price)*num)+price)*quantity;
}
else if (size=='L'&&size=='l')
{
price=425+(0.2*425);
total=(((0.25*price)*num)+price)*quantity;
}
}
else if (type=='M'&&type=='m')
{
if (size=='S'&&size=='s')
{
price=525;
total=(((0.25*price)*num)+price)*quantity;
}
else if (size=='M'&&size=='m')
{
price=525+(0.1*525);
total=(((0.25*price)*num)+price)*quantity;
}
else if (size=='L'&&size=='l')
{
price=525+(0.2*525);
total=(((0.25*price)*num)+price)*quantity;
}
}
System.out.println("The total ammount ="+total+"RM");
Scanner ans1=new Scanner(System.in);
System.out.println("Do you wish to continue(Y/N):");
ans=ans1.next().charAt(0);
}while (ans=='Y'&&ans=='y');