问题
I am creating an android application and my code will loop through the json data and if finds a match to the string that i have placed in ( in this case "Guil Hernandez") , then it will add that name to an array list of hashmaps. I then populate my listview with a simple adapter. Everything is working properly, but my listview will not appear. Am i doing this sorting "algorithm" wrong? Also if you know of a better way to do the sorting to find a match..PLEASE LET ME KNOW. i am still new to this. Thank you in advance!
private void handleResponse() {
if (mNameDataJson == null ) {
// TODO: handle error
} else {
try {
JSONArray namesArray = mNameDataJson.getJSONArray("posts");
ArrayList<HashMap<String , String> > nameArrayList = new ArrayList<HashMap<String, String>>();
for ( int i = 0 ; i < namesArray.length() ; i++ ) {
JSONObject unit = namesArray.getJSONObject(i);
String name = unit.getString(KEY_NAME);
name = Html.fromHtml(name).toString();
String title = unit.getString(KEY_TITLE);
title = Html.fromHtml(title).toString();
HashMap<String , String> hashMap = new HashMap<String, String>();
if (name == "Guil Hernandez") {
hashMap.put(KEY_NAME, name);
hashMap.put(KEY_TITLE, title);
nameArrayList.add(hashMap);
} else {
Log.v(TAG , "no match");
}
}
String[] keys = { KEY_NAME , KEY_TITLE };
int[] ids = {android.R.id.text1 , android.R.id.text2};
SimpleAdapter adapter = new SimpleAdapter(MyActivity.this , nameArrayList , android.R.layout.simple_list_item_2,
keys , ids);
setListAdapter(adapter);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
full code here :
public class MyActivity extends ListActivity {
private JSONObject mNameDataJson;
private final String TAG = MyActivity.class.getSimpleName();
private final String KEY_NAME = "author";
private final String KEY_TITLE = "title";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my);
GetNameData getNameData = new GetNameData();
getNameData.execute();
}
private void handleResponse() {
if (mNameDataJson == null ) {
// TODO: handle error
} else {
try {
JSONArray namesArray = mNameDataJson.getJSONArray("posts");
ArrayList<HashMap<String , String> > nameArrayList = new ArrayList<HashMap<String, String>>();
for ( int i = 0 ; i < namesArray.length() ; i++ ) {
JSONObject unit = namesArray.getJSONObject(i);
String name = unit.getString(KEY_NAME);
name = Html.fromHtml(name).toString();
String title = unit.getString(KEY_TITLE);
title = Html.fromHtml(title).toString();
HashMap<String , String> hashMap = new HashMap<String, String>();
if (name == "Guil Hernandez") {
hashMap.put(KEY_NAME, name);
hashMap.put(KEY_TITLE, title);
nameArrayList.add(hashMap);
} else {
Log.v(TAG , "no match");
}
}
String[] keys = { KEY_NAME , KEY_TITLE };
int[] ids = {android.R.id.text1 , android.R.id.text2};
SimpleAdapter adapter = new SimpleAdapter(MyActivity.this , nameArrayList , android.R.layout.simple_list_item_2,
keys , ids);
setListAdapter(adapter);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
private class GetNameData extends AsyncTask<Object, Void, JSONObject> {
JSONObject jsonResponse = null;
@Override
protected JSONObject doInBackground(Object... objects) {
String nameUrl = "http://blog.teamtreehouse.com/api/get_recent_summary/?count=20";
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url(nameUrl)
.build();
Call call = client.newCall(request);
call.enqueue(new Callback() {
@Override
public void onFailure(Request request, IOException e) {
}
@Override
public void onResponse(Response response) throws IOException {
String responseString = response.body().string();
Log.v(TAG , responseString);
try {
jsonResponse = new JSONObject(responseString);
} catch (JSONException e) {
e.printStackTrace();
}
}
});
return jsonResponse;
}
@Override
protected void onPostExecute(JSONObject jsonObject) {
mNameDataJson = jsonObject;
handleResponse();
}
}
}
回答1:
If you want to compare strings use equals()
. Like this:
if (name.equals("Guil Hernandez")) {
hashMap.put(KEY_NAME, name);
hashMap.put(KEY_TITLE, title);
nameArrayList.add(hashMap);
}
来源:https://stackoverflow.com/questions/28400522/my-simple-adapter-wont-populate-my-listview