Generate and use JSON data instance _android in Android

1, the production of JSON

Copy Code code as follows:

Package com.example.usingjson2;

Import org.json.JSONException;
Import Org.json.JSONObject;

Import Android.os.Bundle;
Import android.app.Activity;

public class Mainactivity extends activity {

@Override
protected void OnCreate (Bundle savedinstancestate) {
Super.oncreate (savedinstancestate);
Setcontentview (R.layout.activity_main);

System.out.println ("\" Hello world\ "");
Jsonobject object = new Jsonobject ();

try {
Object.put ("One", "Yu");
Object.put ("Two", "XI");
Object.put ("Three", "Kuo");
Object.put ("Four", "HI");
System.out.println (object);

catch (Jsonexception e) {
TODO auto-generated Catch block
E.printstacktrace ();
}

}
}

2, the use of JSON

(1) First create a new class in the current package

Copy Code code as follows:

Package Com.example.useingjson;

public class Data {

public static final String jsonstr = "{' arr ': [1,2,3,4], ' dat ': [Yu,xi,kuo]}";
}

(2) calling in the activity

Copy Code code as follows:

Package Com.example.useingjson;

Import Org.json.JSONArray;
Import org.json.JSONException;
Import Org.json.JSONObject;

Import Android.os.Bundle;
Import android.app.Activity;

public class Mainactivity extends activity {

@Override
protected void OnCreate (Bundle savedinstancestate) {
Super.oncreate (savedinstancestate);
Setcontentview (R.layout.activity_main);

System.out.println (DATA.JSONSTR);

try {
Jsonobject jsonobject = new Jsonobject (DATA.JSONSTR);
Jsonarray Jsonarray = Jsonobject.getjsonarray ("arr");
System.out.println (Jsonarray);

for (int i = 0; i < jsonarray.length (); i++)
{
System.out.println (Jsonarray.get (i));
}

Jsonarray jsonArray2 = Jsonobject.getjsonarray ("Dat");
System.out.println (JsonArray2);
for int j = 0; J < Jsonarray2.length (); j + +)
{
System.out.println (Jsonarray2.get (j));
}

catch (Jsonexception e) {
TODO auto-generated Catch block
E.printstacktrace ();
}
}
}

3. Note

The production and use of JSON is two projects, because just contact Android, the code is relatively simple, emphasis on understanding the principle.