$29
Assignment 3 Stock Watch Solution
Uses: Internet, RecyclerView, Option-Menus, Multiple AsyncTasks,
JSON Data, Swipe-Refresh, Dialogs, SQLite Database
App Highlights:
• This app allows the user to display a sorted list of selected stocks. List entries include the stock symbol (and company name), the current price, the daily price change amount and price percent change.
• There is no need to use a different layout for landscape orientation in this application – the same layout should work in any orientation.
• Selected stock symbols and the related names should be stored in the device’s SQLite Database.
• A Stock class should be created to represent each individual stock in the application. Required data includes: Stock Symbol (String), Company Name (String), Price (double), Price Change (double), and Change Percentage (double).
• Clicking on a stock opens a browser displaying the Market Watch web page for that stock
• Swipe-Refresh (pull-down) refreshes stock data.
• The application is made up of only 1 activity, shown below:
Add Stock Options-Menu
Item (shown as Icon)
RecyclerView list of Stocks (list
entries have their own layout)
List scrolls up & down
Long-Click on a Stock entry to
delete (with delete confirmation)
Click on a Stock entry opens a
web browser to the Market
Watch site for the selected stock
© Christopher Hield
1 of 16
CS 442 Mobile Applications
Development (Android Section)
A) Internet Data:
Downloading data for a stock symbol requires 2 downloads – one download to acquire the full set or supported stock symbol and company names, and a second download to acquire the financial data for a particular stock.
Download 1: Stock Symbol & Company Data
When started, your app should initiate a download of the full set or supported stock symbol and company names.
This data is saved, and then used whenever the user the user adds a new stock.
Download Source: https://api.iextrading.com/1.0/ref-data/symbols
Download Results Example:
Results are returned in JSON format, as a JSONArray containing the results data from the query. The data we are interested in is the stock “symbol” and “name”. Below is a sample of the JSON you will download :
[{
"symbol": "A",
}, {
"name": "Agilent Technologies Inc.",
"symbol": "ICXUSDT",
"date": "2018-09-21",
"name": "ICON USD",
"isEnabled": true,
"date": "2018-09-21",
"type": "cs",
"isEnabled": true,
"iexId": "2"
"type": "crypto",
}, {
"iexId": 10000013
"symbol": "AA",
}, {
"name": "Alcoa Corporation",
"symbol": "NEOUSDT",
"date": "2018-09-21",
"name": "NEO USD",
"isEnabled": true,
"date": "2018-09-21",
"type": "cs",
"isEnabled": true,
"iexId": "12042"
"type": "crypto",
}, {
"iexId": 10000014
"symbol": "AAAU",
}, {
"name": "Perth Mint Physical Gold",
"symbol": "VENUSDT",
"date": "2018-09-21",
"name": "VeChain USD",
"isEnabled": true,
"date": "2018-09-21",
"type": "N/A",
"isEnabled": true,
"iexId": "14924"
"type": "crypto",
}, {
"iexId": 10000015
"symbol": "AABA",
}, {
"name": "Altaba Inc.",
"symbol": "XLMUSDT",
"date": "2018-09-21",
"name": "Stellar Lumens USD",
"isEnabled": true,
"date": "2018-09-21",
"type": "cs",
"isEnabled": true,
"iexId": "7653"
"type": "crypto",
}, {
"iexId": 10000016
"symbol": "AAC",
}, {
"name": "AAC Holdings Inc.",
"symbol": "QTUMUSDT",
"date": "2018-09-21",
"name": "Qtum USD",
"isEnabled": true,
"date": "2018-09-21",
"type": "cs",
"isEnabled": true,
"iexId": "9169"
"type": "crypto",
}, {
"iexId": 10000017
. . .
}]
© Christopher Hield
2 of 16
CS 442 Mobile pplications
Development (Android Section)
Download 2: Stock Financial Data
When you have the desired stock symbol (and company name), you use the stock symbol to download financial data for that stock.
Download Source: https://api.iextrading.com
Query Format: https://api.iextrading.com/1.0/stock/stock_symbol/quote?displayPercent=true
For example, if the selected stock symbol was TSLA, your full URL would be:
https://api.iextrading.com/1.0/stock/TSLA/quote?displayPercent=true
Download Results:
Results are returned in JSON format, as a JSONObject containing the results data from the query. The data we are interested in is highlighted below (Example using search text “TSLA”):
{
"symbol":
"TSLA",
"companyName":
"Tesla Inc.",
"delayedPriceTime": 1537560000292,
"primaryExchange": "Nasdaq Global Select",
"extendedPrice": 299.81,
"sector": "Consumer Cyclical",
"extendedChange": 0.71,
"calculationPrice": "close",
"extendedChangePercent": 0.2370000002,
"open": 297.7,
"extendedPriceTime": 1537563572798,
"openTime": 1537536600046,
"previousClose": 298.33,
"close": 299.1,
"change":
0.77,
"closeTime": 1537560000292,
"changePercent":
0.258,
"high": 300.58,
"iexMarketPercent": 0,
"low": 295.37,
"iexVolume": null,
"latestPrice":
299.1,
"avgTotalVolume": 9530433,
"latestSource": "Close",
"iexBidPrice": null,
"latestTime": "September 21, 2018",
"iexBidSize": null,
"latestUpdate": 1537560000292,
"iexAskPrice": null,
"latestVolume": 5034657,
"iexAskSize": null,
"iexRealtimePrice": null,
"marketCap": 51024409370,
"iexRealtimeSize": null,
"peRatio": -18.88,
"iexLastUpdated": null,
"week52High": 387.46,
"delayedPrice": 299.1,
"week52Low": 244.5901,
"ytdChange": -6.427801641032025
}
If the requested stock symbol does not exist, the following is returned: (Example using search text “ZZZZZ”):
Response Code: 404 Not Found
The symbol, companyName, latestPrice, change & changePercentage make up the data for one stock. Your code should parse these 5 data elements.
Using these 5 data elements, you can create a Stock object with all data reflecting the user’s choice.
© Christopher Hield
3 of 16
B) Application Behavior Diagrams:
1) App MainActivity
Each stock entry contains the
Stock Symbol (i.e., AAPL), the
company name (i.e., Apple
Inc.), the Last Trade Price
(135.72), the price change
direction (▲ for positive
Price Change Amount, ▼ for
negative Price Change
Amount), the Price Change
Amount (0.38), and the Price
Change Percentage (0.28%)
in parentheses.
If the stock’s Price Change
Amount is a positive value,
then entire entry should use
a green font. If the Price
Change Amount is a negative
value, then entire entry
should use a red font.
Clicking on a Stock entry opens a
web browser to the Market
Watch website site for the
selected stock
CS 442 Mobile Applications Development (Android Section)
“Add Stock” action is
an Options-Menu
with a single item
(shown as Icon)
A scrollbar should be
present along the
right-hand side
Long-Click on a Stock
entry to delete (with
delete confirmation)
RecyclerView list
entries have their
own layout
© Christopher Hield
4 of 16
CS 442 Mobile Applications
Development (Android Section)
1) Adding a stock – when only one stock matches the search symbol/name search string (NOTE: The Stock Selection dialog should only allow capital letters):
AMZN
2) Adding a stock – when multiple stocks matched the search string (Stock Selection dialog should only allow capital letters, stock selection dialog should display the stock symbol and company name):
© Christopher Hield
5 of 16
CS 442 Mobile Applications
Development (Android Section)
3) Adding a stock with no Network Connection – test using “Airplane Mode” (No buttons on the error dialog):
4) Adding a stock – specified stock is a duplicate (Stock Selection dialog should only allow capital letters, No buttons on the warning dialog):
AMZN
© Christopher Hield
6 of 16
CS 442 Mobile Applications
Development (Android Section)
1) Adding a stock – specified stock is not found (Stock Selection dialog should only allow capital letters, No buttons on the dialog):
WXYZ
6) Swipe-Refresh (pull-down) reloads (re-downloads) all stock data:
Pull
© Christopher Hield
7 of 16
CS 442 Mobile Applications
Development (Android Section)
7) Swipe-Refresh attempt with no network connection (No buttons on the error dialog):
Pull
8) Long-Press on a stock to delete it:
© Christopher Hield
8 of 16
CS 442 Mobile Applications
Development (Android Section)
9) Tap on a stock to open the MarketWatch.com website entry for the selected stock:
MarketWatch URL’s are in the form: http://www.marketwatch.com/investing/stock/some_stock
For example: http://www.marketwatch.com/investing/stock/TSLA
© Christopher Hield
9 of 16
CS 442 Mobile Applications
Development (Android Section)
C) Application Behavior Flowcharts:
a) App Startup
MainActivity
Execute
Get all Stocks from
Connected to
NameDownloader
the DB, store in a
No
onCreate
Network?
AsyncTask
Temporary List
Yes
Startup Process Flow
Show No-Network
Error Dialog
For Each Stock in
the Temporary
Put all stocks in the
Stock List:
display, with price,
change & percent
change as zero.
More
Next Stock
Stocks
No more stocks
to process
Sort Stock List
Notify Adapter
Execute
of Changed
Done
StockDownloader
Dataset
AsyncTask
Notify Adapter
of Changed
RETURN from
Done
Dataset
Add Stock to
Sort Stock List
StockDownloader
Stock List
AsyncTask
b) NameDownloader (AsyncTask)
Download stock
Add symbol &
Connect to data
Parse symbol &
names to
symbols & names
Done
provider via API
name data
symbol:name
JSON
HashMap
c) StockDownloader (AsyncTask)
Using provided stock
Create Stock object
symbol, connect to
Download stock
Parse symbol &
& pass it back to
Done
stock data provider
data JSON
name data
MainActivity
via API
© Christopher Hield
10 of 16
CS 442 Mobile Applications
Development (Android Section)
d) Add New Stock Process
Select
Display Add Stock
Add Stock
Connected to
Menu option
Yes
Symbol Entry
Network?
from Main
Dialog
Activity
No
Get matching
DONE
Show Error Dialog
symbols/names
from
NameDownloader
Did you
Display a list of the
resulting Stock Symbols
No Stock Found
Get a Stock
Multiple Stocks
& Company Names in a
result?
Dialog
Dialog
Cancelled
ONE Stock
Show Error Dialog
Use selected symbol to
execute
Selection Made
StockDownloader
AsyncTask
Yes
DONE
DONE
RETURN from
StockDownloader Duplicate
AsyncTask Stock?
Add Stock Process Flow
No
Add Stock to
Stock List
Sort Stock List
Notify Adapter
of Changed
Dataset
Add Stock to
DB
© Christopher Hield
11 of 16
CS 442 Mobile Applications
Development (Android Section)
e) Swipe-Refresh (pull-down) List:
onSwipe
Get all Stocks from
Connected to
the DB, store in a
No
Refresh
Network?
Temporary List
Yes
SwipeRefresh Process Flow
Show No-Network
Error Dialog
For Each Stock in
the Temporary
Stock List:
More
Next Stock
Stocks
No more stocks
to process
Notify Adapter
Execute
of Changed
Done
StockDownloader
Dataset
AsyncTask
Done
RETURN from
Add Stock to
Sort Stock List
StockDownloader
Stock List
AsyncTask
f) Long-Press Delete Stock:
Delete Stock Process Flow
Long-Click on a
Display Delete Stock
Stock from the
Confirmation
List in Main
Dialog
Activity
Cancelled Done
Confirmed
Delete Stock
Remove Stock
Notify Adapter
of Changed
from DB
from Stock List
Dataset
12 of 16
© Christopher Hield
CS 442 Mobile Applications
Development (Android Section)
D) Database
Your application must store the Stock Symbol and Company Name in the android device’s SQLite database. You will need a Database handler class as we have done in class (you have a posted example of a Database handler that you can use as a model).
StockWatchTable
StockSymbol
CompanyName
AAPL
Apple, Inc
AMZN
Amazon.com, Inc.
…
…
private static final String DATABASE_NAME = “StockAppDB”; private static final String TABLE_NAME = “StockWatchTable”; private static final String SYMBOL = “StockSymbol”; private static final String COMPANY = “CompanyName”;
• DB creation (done in onCreate):
CREATE TABLE TABLE_NAME (
SYMBOL TEXT not null unique,
COMPANY TEXT not null)
• DB Add (Sample method to add a stock to the DB):
public void addStock(Stock stock) {
Log.d(TAG, "addStock: Adding " + stock.getSymbol());
ContentValues values = new ContentValues();
values.put(SYMBOL, stock.getSymbol());
values.put(COMPANY, stock.getCompany());
database.insert(TABLE_NAME, null, values);
Log.d(TAG, "addStock: Add Complete”);
}
• DB Delete (Sample method to delete a stock from the DB):
public void deleteStock(String symbol) {
Log.d(TAG, "deleteStock: Deleting Stock " + symbol);
int cnt = database.delete(
TABLE_NAME, "SYMBOL = ?", new String[] { symbol });
Log.d(TAG, "deleteStock: " + cnt);
}
© Christopher Hield
13 of 16
CS 442 Mobile Applications
Development (Android Section)
• DB Load All (Sample method to get all stock-company entries from the DB):
public ArrayList<String[]> loadStocks() {
ArrayList<String[]> stocks = new ArrayList<>();
Cursor cursor = database.query(
TABLE_NAME, // The table to query
new String[]{SYMBOL, COMPANY}, // The columns to return null, // The columns for the WHERE clause null, // The values for the WHERE clause
null, // don't group the rows
null, // don't filter by row groups
null); // The sort order
if (cursor != null) {
cursor.moveToFirst();
for (int i = 0; i < cursor.getCount(); i++) { String symbol = cursor.getString(0); String company = cursor.getString(1); stocks.add(new String[]{symbol, company}); cursor.moveToNext();
}
cursor.close();
}
return stocks;
}
© Christopher Hield
14 of 16
CS 442 Mobile Applications
Development (Android Section)
E) Development Plan
1) Create the base app:
a. MainActivity with RecyclerView & SwipeRefreshLayout
b. Stock Class
c. RecyclerView Adapter
d. RecyclerView ViewHolder
e. Create fake “dummy” stocks to populate the list in the MainActivity onCreate.
f. Add the onClick and onLongClick methods. The onLongClick should delete an entry. The onClick can open a Toast message for now.
g. Add Stock options-menu opens dialog, on confirmation you can open a Toast message for now.
h. SwipeRefresh callback method can open a Toast message for now.
2) Add the database elements:
a. Create the database handler.
b. Add database handler calls to MainActivity (load, add, delete)
c. Code the onClick method to open the browser to the stock’s Market Watch site.
3) Add the internet elements and final integration:
a. Create the Stock Symbol - Company Name downloader/parser AsyncTask (http://d.yimg.com/aq/autoc)
b. Create the Stock Financial Data downloader/parser AsyncTask (finance.google.com)
c. Add a method to MainActivity that allows the Stock Symbol - Company Name downloader/parser AsyncTask to send the newly downloaded Stock Symbol & Company Name data back to MainActivity. This method should create and execute the Stock Financial Data downloader/parser AsyncTask.
d. Add a method to MainActivity that allows the Stock Financial Data downloader/parser AsyncTask to send the newly created Stock back to MainActivity.
e. Implement the Add Stock feature (this uses the results of the above tasks)
f. Implement the SwipeRefresh callback to re-download the Stock Financial Data for the loaded stocks
g. Add alerts when startup, add, & refresh are attempted when no internet connection is available.
© Christopher Hield
15 of 16
CS 442 Mobile Applications
Development (Android Section)
Assignment Assistance
The TAs for our course is available to assist you with your assignment if needed. Questions on assignment requirements and course concepts can be sent to the instructor.
Submissions & Grading
1) Submissions must consist of your zipped project folder (please execute Build =>Clean Project before generating the zip file).
2) Submissions should reflect the concepts and practices we cover in class, and the requirements specified in this document.
3) Late submissions will be penalized by 10% per class late. (i.e., from one second late to 1 class late: 10% penalty, from one class plus one second late to 2 classes late: 20% penalty, etc.).
4) Grading will be based upon the presence and proper functionality of all features and behaviors described in this document.
NOTE
This assignment is worth 300 points. This means (for example) that if you get 89% on this assignment, your recorded score will be:
(89% * 300 points = 267 points)
Note that this also means that the 10% late submission penalty will be 10% * 300 points = 30 points.
If you do not understand anything in this handout, please ask.
Otherwise the assumption is that you understand the content.
Unsure? Ask!
© Christopher Hield
16 of 16
