Android Question json help

tufanv · Dec 19, 2016

Hello

I have a json retrieved from remote web

B4X:

{"time":{"updated":"Dec 19, 2016 12:30:00 UTC","updatedISO":"2016-12-19T12:30:00+00:00","updateduk":"Dec 19, 2016 at 12:30 GMT"},"bpi":{"USD":{"code":"USD","rate":"791.3488","description":"United States Dollar","rate_float":791.3488},"TRY":{"code":"TRY","rate":"2,770.3276","description":"Turkish Lira","rate_float":2770.3276}}}

I got this with httpjob and used the code below :

B4X:

Dim parser As JSONParser
parser.Initialize(res)
dim m as map = parser.nextobject

log m gives me :

B4X:

    time = "(read only map) {\n    updated = \"Dec 19, 2016 12:34:00 UTC\";\n    updatedISO = \"2016-12-19T12:34:00+00:00\";\n    updateduk = \"Dec 19, 2016 at 12:34 GMT\";\n}";
}
{"time":{"updated":"Dec 19, 2016 12:34:00 UTC","updatedISO":"2016-12-19T12:34:00+00:00","updateduk":"Dec 19, 2016 at 12:34 GMT"},"bpi":{"USD":{"code":"USD","rate":"791.0175","description":"United States Dollar","rate_float":791.0175},"TRY":{"code":"TRY","rate":"2,770.3276","description":"Turkish Lira","rate_float":2770.3276}}}
code":"TRY","rate":"2,770.3276","description"

How can i retrieve the "rate_float" from this map ? m.get("rate_float") is not working.

TY

DonManfred · Dec 19, 2016

B4X:

Dim parser As JSONParser
parser.Initialize(<text>)
Dim root As Map = parser.NextObject
Dim bpi As Map = root.Get("bpi")
Dim USD As Map = bpi.Get("USD")
Dim rate_float As Double = USD.Get("rate_float")
Dim code As String = USD.Get("code")
Dim rate As String = USD.Get("rate")
Dim description As String = USD.Get("description")
Dim mytry As Map = bpi.Get("TRY")
Dim rate_float As Double = mytry.Get("rate_float")
Dim code As String = mytry.Get("code")
Dim rate As String = mytry.Get("rate")
Dim description As String = mytry.Get("description")
Dim time As Map = root.Get("time")
Dim updateduk As String = time.Get("updateduk")
Dim updatedISO As String = time.Get("updatedISO")
Dim updated As String = time.Get("updated")

tufanv · Dec 19, 2016

DonManfred said:

B4X:

Dim parser As JSONParser
parser.Initialize(<text>)
Dim root As Map = parser.NextObject
Dim bpi As Map = root.Get("bpi")
Dim USD As Map = bpi.Get("USD")
Dim rate_float As Double = USD.Get("rate_float")
Dim code As String = USD.Get("code")
Dim rate As String = USD.Get("rate")
Dim description As String = USD.Get("description")
Dim mytry As Map = bpi.Get("TRY")
Dim rate_float As Double = mytry.Get("rate_float")
Dim code As String = mytry.Get("code")
Dim rate As String = mytry.Get("rate")
Dim description As String = mytry.Get("description")
Dim time As Map = root.Get("time")
Dim updateduk As String = time.Get("updateduk")
Dim updatedISO As String = time.Get("updatedISO")
Dim updated As String = time.Get("updated")

Dear Donmanfred ,
Couldnt have been better ! Thanks very mu8ch

tufanv · Dec 19, 2016

DonManfred said:

B4X:

Dim parser As JSONParser
parser.Initialize(<text>)
Dim root As Map = parser.NextObject
Dim bpi As Map = root.Get("bpi")
Dim USD As Map = bpi.Get("USD")
Dim rate_float As Double = USD.Get("rate_float")
Dim code As String = USD.Get("code")
Dim rate As String = USD.Get("rate")
Dim description As String = USD.Get("description")
Dim mytry As Map = bpi.Get("TRY")
Dim rate_float As Double = mytry.Get("rate_float")
Dim code As String = mytry.Get("code")
Dim rate As String = mytry.Get("rate")
Dim description As String = mytry.Get("description")
Dim time As Map = root.Get("time")
Dim updateduk As String = time.Get("updateduk")
Dim updatedISO As String = time.Get("updatedISO")
Dim updated As String = time.Get("updated")

by the way is it possible to get the price of date as the date is changing everyday: I mean this is the json :

B4X:

{"bpi":{"2016-12-18":2760.045},"disclaimer":"This data was produced from the CoinDesk Bitcoin Price Index. BPI value data returned as TRY.","time":{"updated":"Dec 19, 2016 00:03:00 UTC","updatedISO":"2016-12-19T00:03:00+00:00"}}

2016-12-18 is the yesterdays date . but the date changes everyday so tonorrow the json will be :

B4X:

{"bpi":{"2016-12-19":2760.045},"disclaimer":"This data was produced from the CoinDesk Bitcoin Price Index. BPI value data returned as TRY.","time":{"updated":"Dec 19, 2016 00:03:00 UTC","updatedISO":"2016-12-19T00:03:00+00:00"}}

so to get 2760.045 i must find another way . i tried :

B4X:

            Dim Yesterday As Long
            Yesterday = DateTime.add(DateTime.Now, 0, 0, -1)

            DateTime.DateFormat = "yyyy-MM-dd"
            Dim tarih As String = Yesterday
            Log (DateTime.Date(Yesterday))
            Dim oldprice As String =bpi.Get(tarih)
            Log(oldprice)

this gives me null altough the tarih is "2016-12-18" just like in the json. Where am i wrong at this ?

tufanv · Dec 19, 2016

ah i was wrong at tarih date
i changed it to
Dim tarih As String = DateTime.Date(Yesterday)
and it is ok now! Thanks !

tufanv · Dec 19, 2016

I have another question about this. Another website api gives the data not in json but like this :

B4X:

[
    {
        "symbol": "BTC",
        "rank": "1",
        "price_usd": "791.445",
        "price_btc": "1.0",
        "24h_volume_usd": "64509000.0",
        "market_cap_usd": "12704066990.0",
        "available_supply": "16051737.0",
        "total_supply": "16051737.0",
        "percent_change_1h": "-0.17",
        "percent_change_24h": "0.21",
        "percent_change_7d": "1.44",
        "last_updated": "1482154472"
    }
]

i cant load this into directly map and i cant use json as this is not json. How can i use this most efffectively. This is like a map but it is not. I cant load this into a map.

tigrot · Dec 19, 2016

It's a JSON record as far as I can see. Or I don't understand you question...

Mahares · Dec 19, 2016

It is json I think (list containg map: Here is a link to the json tree. Copy and paste your string and click 'parse'. You will see the results.
http://basic4ppc.com:51042/json/index.html

KMatle · Dec 19, 2016

http://www.b4x.com:51042/json/index.html

Just Copy & Paste and see the magic

tufanv · Dec 19, 2016

KMatle said:
http://www.b4x.com:51042/json/index.html

Just Copy & Paste and see the magic

it is really magic ! thanks

KMatle · Dec 19, 2016

Generally:

[ = List
{ = Map

"x": "y" = Key/Value pair inside a map

{{ = map in a map

So {Mymap:{"Name":"Klaus","Age":"48"}}

is a Map which contains a Map with two entries (following the rule { = Map)

This is a list of two maps (see the [ for a list)

[{Mymap1:{"Name":"Klaus","Age":"48"}},{Mymap2:{"Name":"Klaus","Age":"48"}}]

tigrot · Dec 19, 2016

KMatle said:
http://www.b4x.com:51042/json/index.html

Just Copy & Paste and see the magic

And I spent one day to verify the format of my JSON (or should I say JSOB!)...
Never stop to learn... Thank you for stuff!

KMatle · Dec 19, 2016

It's Erel's

But I'm lazy so I know that little helpers

tufanv · Dec 20, 2016

KMatle said:
It's Erel's But I'm lazy so I know that little helpers

Yes it is a very good tool. I have one more question. I have a data like this :

B4X:

{"bpi":{"2016-11-19":2529.4387,"2016-11-20":2457.4058,"2016-11-21":2476.4122,"2016-11-22":2530.4663,"2016-11-23":2513.7142,"2016-11-24":2531.443,"2016-11-25":2542.4719,"2016-11-26":2529.0364,"2016-11-27":2510.9517,"2016-11-28":2504.2451,"2016-11-29":2497.8719,"2016-11-30":2546.3946,"2016-12-01":2625.2549,"2016-12-02":2706.7649,"2016-12-03":2690.9782,"2016-12-04":2700.1562,"2016-12-05":2644.3883,"2016-12-06":2626.8372,"2016-12-07":2605.1403,"2016-12-08":2634.9333,"2016-12-09":2668.2762,"2016-12-10":2687.8108,"2016-12-11":2680.393,"2016-12-12":2702.0001,"2016-12-13":2708.1274,"2016-12-14":2735.3231,"2016-12-15":2716.8577,"2016-12-16":2739.7886,"2016-12-17":2763.9442,"2016-12-18":2760.045,"2016-12-19":2792.4361}}

the keys are dynamic so i cant use m.get(date) like things to get the value. Is there a way to get only the values because keys will be changing everyday.

KMatle · Dec 20, 2016

tufanv said:
Is there a way to get only the values

Just take a look at the methods of a map (f.e. GetValueAt)

DonManfred · Dec 20, 2016

You need to learn how the json look like and parse it yourself.
get the root map/list and work with it yourself to find all items.

tufanv · Dec 20, 2016

DonManfred said:
You need to learn how the json look like and parse it yourself.
get the root map/list and work with it yourself to find all items.

yeah i did that and i have a different problem. I extracted the map with json parse and i used map.values to list all values but they are not ordered as they are in the map.first portion shows the map and it starts with 2529.4387 but when i use map.values it is in a total different sequence. Yes i can find a way to get them one by one but there must be a easier way for this.

B4X:

(read only map) {
    "2016-11-19" = "2529.4387";
    "2016-11-20" = "2457.4058";
    "2016-11-21" = "2476.4122";
    "2016-11-22" = "2530.4663";
    "2016-11-23" = "2513.7142";
    "2016-11-24" = "2531.443";
    "2016-11-25" = "2542.4719";
    "2016-11-26" = "2529.0364";
    "2016-11-27" = "2510.9517";
    "2016-11-28" = "2504.2451";
    "2016-11-29" = "2497.8719";
    "2016-11-30" = "2546.3946";
    "2016-12-01" = "2625.2549";
    "2016-12-02" = "2706.7649";
    "2016-12-03" = "2690.9782";
    "2016-12-04" = "2700.1562";
    "2016-12-05" = "2644.3883";
    "2016-12-06" = "2626.8372";
    "2016-12-07" = "2605.1403";
    "2016-12-08" = "2634.9333";
    "2016-12-09" = "2668.2762";
    "2016-12-10" = "2687.8108";
    "2016-12-11" = "2680.393";
    "2016-12-12" = "2702.0001";
    "2016-12-13" = "2708.1274";
    "2016-12-14" = "2735.3231";
    "2016-12-15" = "2716.8577";
    "2016-12-16" = "2739.7886";
    "2016-12-17" = "2763.9442";
    "2016-12-18" = "2760.045";
    "2016-12-19" = "2792.4361";
}
<B4IList: (
    "2687.8108",
    "2680.393",
    "2702.0001",
    "2708.1274",
    "2735.3231",
    "2716.8577",
    "2739.7886",
    "2763.9442",
    "2760.045",
    "2792.4361",
    "2529.4387",
    "2457.4058",
    "2476.4122",
    "2530.4663",
    "2513.7142",
    "2531.443",
    "2542.4719",
    "2529.0364",
    "2510.9517",
    "2504.2451",
    "2497.8719",
    "2546.3946",
    "2625.2549",
    "2706.7649",
    "2690.9782",
    "2700.1562",
    "2644.3883",
    "2626.8372",
    "2605.1403",
    "2634.9333",
    "2668.2762"
)>

DonManfred · Dec 20, 2016

tufanv said:
not ordered

it is documented that this can happen using json parsing.

The order does not matter.
Get the data, store it in your database and order the data by your wishes using querying your database.

tufanv · Dec 20, 2016

in case someone needs in the future , I solved id with the code below :

B4X:

            Dim parser As JSONParser
            parser.Initialize(res)
            Dim root3 As Map = parser.NextObject
            Dim bpi As Map = root3.Get("bpi")
            For i=30 To 1 Step-1
                Dim Yesterday As Long
           
                Yesterday = DateTime.add(DateTime.Now, 0, 0, -i)

                DateTime.DateFormat = "yyyy-MM-dd"
                Dim tarih As String = DateTime.Date(Yesterday)
                Log(bpi.Get(tarih))
            Next

KMatle · Dec 20, 2016

tufanv said:
{"bpi":{"2016-11-19":2529.4387,"2016-11-20":2457.4058,"2016-11-21":2476.4122,"2016-11-22":2530.4663,"2016-11-23":2513.7142,"2016-11-24":2531.443,"2016-11-25":2542.4719,"2016-11-26":2529.0364,"2016-11-27":2510.9517,"2016-11-28":2504.2451,"2016-11-29":2497.8719,"2016-11-30":2546.3946,"2016-12-01":2625.2549,"2016-12-02":2706.7649,"2016-12-03":2690.9782,"2016-12-04":2700.1562,"2016-12-05":2644.3883,"2016-12-06":2626.8372,"2016-12-07":2605.1403,"2016-12-08":2634.9333,"2016-12-09":2668.2762,"2016-12-10":2687.8108,"2016-12-11":2680.393,"2016-12-12":2702.0001,"2016-12-13":2708.1274,"2016-12-14":2735.3231,"2016-12-15":2716.8577,"2016-12-16":2739.7886,"2016-12-17":2763.9442,"2016-12-18":2760.045,"2016-12-19":2792.4361}}

This is just a map inside a map -> brackets {} = maps. So let's follow this thought:

A map contains a key/value pair. Both are delimited by a ":". So guess what the key and the value is? (Hint: Key is "bpi" and value everything behind the ":").

So if "everything behing the : is the value" is true. What is the content of the value then? It starts with a bracket. Following the simple rule it MUST be a map.
Let's check that:

1. Does it start with a {? Yes!
2. What do we know? It must be a map.
3. Is it a map? Yes, because it has key/value fields delimited by ":"

So the value of the key "bpi" is another map! Maps can contain almost enything, even maps as a value.

Let's check if we find the corresponding code:

B4X:

Dim JustAString As String = $"{"bpi":{"2016-11-19":2529.4387,"2016-11-20":2457.4058,"2016-11-21":2476.4122,"2016-11-22":2530.4663,"2016-11-23":2513.7142,"2016-11-24":2531.443,"2016-11-25":2542.4719,"2016-11-26":2529.0364,"2016-11-27":2510.9517,"2016-11-28":2504.2451,"2016-11-29":2497.8719,"2016-11-30":2546.3946,"2016-12-01":2625.2549,"2016-12-02":2706.7649,"2016-12-03":2690.9782,"2016-12-04":2700.1562,"2016-12-05":2644.3883,"2016-12-06":2626.8372,"2016-12-07":2605.1403,"2016-12-08":2634.9333,"2016-12-09":2668.2762,"2016-12-10":2687.8108,"2016-12-11":2680.393,"2016-12-12":2702.0001,"2016-12-13":2708.1274,"2016-12-14":2735.3231,"2016-12-15":2716.8577,"2016-12-16":2739.7886,"2016-12-17":2763.9442,"2016-12-18":2760.045,"2016-12-19":2792.4361}}"$
    Log(JustAString)
  
    Dim parser As JSONParser
    parser.Initialize(JustAString)
  
    Dim MainMap, MapInTheMap As Map
    MainMap=parser.Nextobject
    Log(MainMap.Get("bpi"))
    MapInTheMap=MainMap.Get("bpi")

1. First it's just a string (which will be returned from f.e. a Job)
2. Let's initialize the parser with it and get the next object and put it in a map
3. Again: Why does he know that the whole thing must be a map? (Hint: I took a look at the string and... You know the answer)
4. Now I know that the key is bpi and the value must be a map, too (everything behind the : is the va....)
5 Let's get it by the key "bpi" and put it in a map (because it is one)

What if....

The whole thing starts with a [ ? Hm... Looks like a list. So put it in a list. Can lists contain maps? Of course!

Android Question json help

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