我正在将 JSON 数据解析到数据库中，该数据显示在我的 lisview 中。但是它第一次从我的 JSON 中获取数据并存储在 db 中，如果我在我的网站中添加任何内容，它不会升级，json 也会增加但它不会反映在数据库中，数据库部分也没有升级。只是它只是显示第一个获取的数据。
Ginfydbadapter.java
public class GinfyDbAdapter {
private static final String DATABASE_NAME = "test";
private static final String DATABASE_TABLE_PROJ = "projects";
private static final int DATABASE_VERSION = 3;
public static final String CATEGORY_COLUMN_ID = "_id";
public static final String CATEGORY_COLUMN_TITLE = "title";
public static final String CATEGORY_COLUMN_CONTENT = "content";
public static final String CATEGORY_COLUMN_COUNT = "count";
private static final String TAG = "GinfyDbAdapter";
private DatabaseHelper mDbHelper;
private static SQLiteDatabase mDb;
private final Context mCtx;
public void saveCategoryRecord(String id, String title, String content, String count) {
ContentValues contentValues = new ContentValues();
contentValues.put(CATEGORY_COLUMN_ID, id);
contentValues.put(CATEGORY_COLUMN_TITLE, title);
contentValues.put(CATEGORY_COLUMN_CONTENT, content);
contentValues.put(CATEGORY_COLUMN_COUNT, count);
mDb.insert(DATABASE_NAME, null, contentValues);
}
public Cursor getTimeRecordList() {
return mDb.rawQuery("select * from " + DATABASE_NAME, null);
}
private static class DatabaseHelper extends SQLiteOpenHelper {
DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
private static final String DATABASE_CREATE_PROJ =
"create table " + DATABASE_TABLE_PROJ + " ("
+ CATEGORY_COLUMN_ID + " integer primary key , "
+ CATEGORY_COLUMN_TITLE + " text not null, " + CATEGORY_COLUMN_CONTENT + " text not null, " + CATEGORY_COLUMN_COUNT + " integer );" ;
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
String DATABASE_CREATE_PROJ = "CREATE TABLE " + DATABASE_TABLE_PROJ + "( "
+ CATEGORY_COLUMN_ID + " integer primary key, "
+ CATEGORY_COLUMN_TITLE + " text not null, " + CATEGORY_COLUMN_CONTENT + " text not null, " + CATEGORY_COLUMN_COUNT + " integer );" ;
db.execSQL(DATABASE_CREATE_PROJ);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
db.execSQL("DROP TABLE IF EXISTS"+ DATABASE_TABLE_PROJ);
onCreate(db);
}
}
public void saveCategoryRecord(Category category) {
ContentValues values = new ContentValues();
values.put(CATEGORY_COLUMN_TITLE , category.getTitle());
values.put(CATEGORY_COLUMN_CONTENT, category.getContent());
values.put(CATEGORY_COLUMN_COUNT, category.getCount());
// Inserting Row
mDb.insert(DATABASE_TABLE_PROJ, null, values);
mDb.close(); // Closing database connection
}
public Cursor fetchAllProjects() {
// TODO Auto-generated method stub
return mDb.query(DATABASE_TABLE_PROJ, new String[] {CATEGORY_COLUMN_ID, CATEGORY_COLUMN_TITLE, CATEGORY_COLUMN_CONTENT, CATEGORY_COLUMN_COUNT }, null, null, null, null, null);
}
public GinfyDbAdapter(Context ctx) {
this.mCtx = ctx;
}
public GinfyDbAdapter open() throws SQLException {
mDbHelper = new DatabaseHelper(mCtx);
mDb = mDbHelper.getWritableDatabase();
return this;
}
}
这是我的 MainActivity.java 这里只有我提到我的 json url
@Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_list_item);
mDbHelper=new GinfyDbAdapter(MainActivity.this);
mDbHelper.open();
Cursor projectsCursor = mDbHelper.fetchAllProjects();
if(projectsCursor!=null)
{
fillData(projectsCursor);
Log.i("filling", "...");
}
else
{
new GetDataAsyncTask().execute();
}
//lv1 =(ListView)findViewById(R.id.list);
//lv =(ListView)findViewById(R.id.list);
btnGetSelected = (Button) findViewById(R.id.btnget);
btnGetSelected.setOnClickListener(this);
myFilter = (EditText) findViewById(R.id.myFilter);
//praycount.setOnClickListener(this);
//initView();
}
/*private void initView(){
// show progress dialog
dialog = ProgressDialog.show(this, "", "Loading...");
String url = "http://www.ginfy.com/api/v1/posts.json";
FetchDataTask task = new FetchDataTask(this);
task.execute(url);
} */
private class GetDataAsyncTask extends AsyncTask<Void, Void, Void> {
private ProgressDialog Dialog = new ProgressDialog(MainActivity.this);
protected void onPreExecute() {
Dialog.setMessage("Loading.....");
Dialog.show();
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
Dialog.dismiss();
Cursor projectsCursor = mDbHelper.fetchAllProjects();
if(projectsCursor!=null)
{
mDbHelper=new GinfyDbAdapter(MainActivity.this);
mDbHelper.open();
fillData(projectsCursor);
}
}
@Override
protected Void doInBackground(Void... params) {
getData();
return null;
}
}
public void getData() {
try
{
HttpClient httpclient = new DefaultHttpClient();
httpclient.getParams().setParameter(CoreProtocolPNames.PROTOCOL_VERSION, HttpVersion.HTTP_1_1);
HttpGet request = new HttpGet("https://ancient-caverns-4909.herokuapp.com/api/v1/posts.json");
// HttpGet request = new HttpGet("http://gdata.youtube.com/feeds/api/users/mbbangalore/uploads?v=2&alt=jsonc");
HttpResponse response = httpclient.execute(request);
HttpEntity resEntity = response.getEntity();
String _response=EntityUtils.toString(resEntity); // content will be consume only once
Log.i("................",_response);
httpclient.getConnectionManager().shutdown();
JSONObject jsonObject = new JSONObject(_response);
JSONArray contacts = jsonObject.getJSONArray("post");//(url);
for(int i = 0; i < contacts.length(); i++){
JSONObject c = contacts.getJSONObject(i);
String id = c.getString("id");
String title = c.getString("title");
String content = c.getString("content");
String count = c.getString("count");
mDbHelper=new GinfyDbAdapter(MainActivity.this);
mDbHelper.open();
mDbHelper.saveCategoryRecord(new Category(id,title,content,count));
}
} catch (Exception e) {
e.printStackTrace();
}
}
@SuppressLint("NewApi")
@SuppressWarnings("deprecation")
private void fillData(Cursor projectsCursor) {
//mDbHelper.open();
if(projectsCursor!=null)
{
String[] from = new String[]{GinfyDbAdapter.CATEGORY_COLUMN_TITLE, GinfyDbAdapter.CATEGORY_COLUMN_CONTENT, GinfyDbAdapter.CATEGORY_COLUMN_COUNT};
int[] to = new int[]{R.id.text2, R.id.text1, R.id.count};
dataAdapter = new SimpleCursorAdapter(
this, R.layout.activity_row,
projectsCursor,
from,
to,
0);
setListAdapter(dataAdapter);
}else
{
Log.i("...........","null");
}
}
由于 JSON 更改，我的数据库没有升级，它只需要一次 json 数据。