我的简单适配器不会填充我的列表视图
My Simple Adapter Wont Populate my listview
我正在创建一个 android 应用程序,我的代码将循环遍历 json 数据,如果找到与我放入的字符串的匹配项(在本例中为 "Guil Hernandez" ) ,然后它会将该名称添加到哈希图的数组列表中。然后我用一个简单的适配器填充我的列表视图。一切正常,但我的列表视图不会出现。我做这个排序 "algorithm" 错了吗?另外,如果您知道进行排序以找到匹配项的更好方法……请告诉我。我对此还是陌生的。提前致谢!
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();
}
}
}
完整代码在这里:
public class MyActivity 扩展了 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();
}
}
}
如果要比较字符串,请使用 equals()
。像这样:
if (name.equals("Guil Hernandez")) {
hashMap.put(KEY_NAME, name);
hashMap.put(KEY_TITLE, title);
nameArrayList.add(hashMap);
}
我正在创建一个 android 应用程序,我的代码将循环遍历 json 数据,如果找到与我放入的字符串的匹配项(在本例中为 "Guil Hernandez" ) ,然后它会将该名称添加到哈希图的数组列表中。然后我用一个简单的适配器填充我的列表视图。一切正常,但我的列表视图不会出现。我做这个排序 "algorithm" 错了吗?另外,如果您知道进行排序以找到匹配项的更好方法……请告诉我。我对此还是陌生的。提前致谢!
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();
}
}
}
完整代码在这里:
public class MyActivity 扩展了 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();
}
}
}
如果要比较字符串,请使用 equals()
。像这样:
if (name.equals("Guil Hernandez")) {
hashMap.put(KEY_NAME, name);
hashMap.put(KEY_TITLE, title);
nameArrayList.add(hashMap);
}