我正在创建一个离线工作的应用程序。我的应用程序在在线模式下运行良好并从 url 获取 json。我怎样才能让它离线工作？如何将 json 从 url 插入 SQLite？我想先从 url 获取所有数据，然后将其插入 SQLite，然后使用数据库。
这是我的完整代码：
public class MainActivity extends Activity {
CategoryListAdapter3 cla;
static ArrayList<Long> Category_ID = new ArrayList<Long>();
static ArrayList<String> Category_name = new ArrayList<String>();
static ArrayList<String> Category_image = new ArrayList<String>();
String URL, URL2;
String SelectMenuAPI;
String _response;
String status;
GridView gridview;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
gridview = (GridView) findViewById(R.id.gridview);
cla = new CategoryListAdapter3(MainActivity.this);
new TheTask().execute();
gridview.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> arg0, View arg1,
int position, long arg3) {
// TODO Auto-generated method stub
Intent iMenuList = new Intent(MainActivity.this,
Subcategory.class);
iMenuList.putExtra("Category_ID",
Category_ID.get(position));
iMenuList.putExtra("Category_name",
Category_name.get(position));
startActivity(iMenuList);
}
});
}
void clearData() {
Category_ID.clear();
Category_name.clear();
Category_image.clear();
}
public class TheTask extends AsyncTask<Void, String, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
}
@Override
protected String doInBackground(Void... arg0) {
SelectMenuAPI = "http://www.syddddds.pk/beta7/_webservices
/mobile_api.php?response=getmaincategories";
clearData();
URL = SelectMenuAPI;
URL2 = URL.replace(" ", "%20");
try {
Log.i("url", "" + URL2);
HttpClient client = new DefaultHttpClient();
HttpGet request = new HttpGet(URL2);
HttpResponse response = client.execute(request);
HttpEntity resEntity = response.getEntity();
_response = EntityUtils.toString(resEntity);
} catch (Exception e) {
e.printStackTrace();
}
return _response;
}
@Override
protected void onPostExecute(String result) {
super.onPostExecute(result);
try {
JSONObject json2 = new JSONObject(result);
status = json2.getString("Status");
if (status.equals("1")) {
JSONArray school2 = json2.getJSONArray("data");
//
for (int i = 0; i < school2.length(); i++) {
JSONObject object = school2.getJSONObject(i);
Category_ID.add(Long.parseLong(object .getString("category_id")));
Category_name.add(object.getString("name"));
Category_image.add(object.getString("image_path"));
}
}
else {
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
gridview.setAdapter(cla);
cla.notifyDataSetChanged();
}
}
public class CategoryListAdapter3 extends BaseAdapter {
private Activity activity;
private AQuery androidAQuery;
public CategoryListAdapter3(Activity act) {
this.activity = act;
// imageLoader = new ImageLoader(act);
}
public int getCount() {
// TODO Auto-generated method stub
return MainActivity.Category_ID.size();
}
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ViewHolder holder;
androidAQuery = new AQuery(getcontext());
if(convertView == null){
LayoutInflater inflater = (LayoutInflater) activity
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.viewitem2, null);
holder = new ViewHolder();
convertView.setTag(holder);
}else{
holder = (ViewHolder) convertView.getTag();
}
holder.txtText = (TextView) convertView.findViewById(R.id.title2);
holder.imgThumb = (ImageView) convertView.findViewById(R.id.image2);
holder.txtText.setText(MainActivity.Category_name.get(position));
androidAQuery.id(holder.imgThumb).image(MainActivity.Category_image.get(position),
true, true);
return convertView;
}
private Activity getcontext() {
// TODO Auto-generated method stub
return null;
}
static class ViewHolder {
TextView txtText;
ImageView imgThumb;
}
}