当互联网开启但当我进入离线模式时，它不会在高速缓冲存储器中显示我之前加载的图像。我的主要类的代码在我尝试离线工作时直接转到json数组这是错误的。 ..
public class MainActivity extends Activity {
private static final String TAG = MainActivity.class.getSimpleName();
private ListView listView;
private CustomListAdapter listAdapter;
private List<item> items;
private ProgressDialog mdialog;
private String URL_FEED = "json URL"
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = (ListView) findViewById(R.id.list);
items = new ArrayList<item>();
listAdapter = new CustomListAdapter(this, items);
listView.setAdapter(listAdapter);
Cache cache = AppController.getInstance().getRequestQueue().getCache();
Entry entry = cache.get(URL_FEED);
if (entry != null)
{
// fetch the data from cache
try {
String data = new String(entry.data, "UTF-8");
Log.d("Internet NO", "Response: " + data);
try {
//parseJsonFeed(new JSONObject(data));
JSONArray jsonArray=new JSONArray(data);
setData(jsonArray,true);
Toast.makeText(getApplicationContext(), "Loading from cache.", Toast.LENGTH_SHORT).show();
} catch (JSONException e) {
e.printStackTrace();
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}else {
callJsonArrayRequest();` }
}
private void callJsonArrayRequest()
{
// TODO Auto-generated method stub
// showDialog();
JsonArrayRequest jsonarrayReq = new JsonArrayRequest(URL_FEED,
new Response.Listener<JSONArray>() {
@Override
public void onResponse(JSONArray response) {
setData(response,false);
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
VolleyLog.d(TAG, "Error: " + error.getMessage());
Toast.makeText(getApplicationContext(),
error.getMessage(), Toast.LENGTH_SHORT).show();
//dismissDialog();
}
});
// Adding request to request queue
AppController.getInstance().addToRequestQueue(jsonarrayReq);
}
private void setData(JSONArray response, Boolean isCache) {
Log.d(TAG, response.toString());
try {
for (int i = 0; i < response.length(); i++) {
JSONObject person = (JSONObject) response.get(i);
item model=new item();
model.setSname(person.getString("Name"));
model.setPimage(person.getString("image"));
items.add(model);
}
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(getApplicationContext(),"Error: " + e.getMessage(),Toast.LENGTH_LONG).show();
}
listAdapter.notifyDataSetChanged();
if(!isCache){
Toast.makeText(getApplicationContext(), "Cache not available..Loading from service", Toast.LENGTH_SHORT).show();
//dismissDialog();
}
}
`