我按照本教程制作了一个自定义适配器：
http://www.ezzylearning.com/tutorial.aspx?tid=1763429
我更改了自定义适配器以匹配我的类，需要看起来像这样：
package com.example.beerportfoliopro;
public class BeerSearchAdapter extends ArrayAdapter<BeerData>{
Context context;
int layoutResourceId;
BeerData data[] = null;
public BeerSearchAdapter(Context context, int layoutResourceId, BeerData[] data) {
super(context, layoutResourceId, data);
this.layoutResourceId = layoutResourceId;
this.context = context;
this.data = data;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = convertView;
beerHolder holder = null;
if(row == null)
{
LayoutInflater inflater = ((Activity)context).getLayoutInflater();
row = inflater.inflate(layoutResourceId, parent, false);
holder = new beerHolder();
holder.txtBrewery = (TextView)row.findViewById(R.id.beerBreweryNameList);
holder.txtTitle = (TextView)row.findViewById(R.id.beerNameList);
row.setTag(holder);
}
else
{
holder = (beerHolder)row.getTag();
}
BeerData beer = data[position];
holder.txtTitle.setText(beer.beerName);
holder.txtBrewery.setText(beer.beerBreweryName);
return row;
}
static class beerHolder
{
TextView txtBrewery;
TextView txtTitle;
}
}
我尝试拨打适配器时遇到的错误是：
The constructor BeerSearchAdapter(Search, int, List<BeerData>) is undefined
我正在调用适配器：
//update listview
BeerSearchAdapter adapter1 = new BeerSearchAdapter(Search.this ,R.layout.listview_item_row, beerList);
lv.setAdapter(adapter1);
我的完整Search.java是：
package com.example.beerportfoliopro;
public class Search extends Activity implements OnQueryTextListener {
private ListView lv;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.d("logIN", "starting activity");
setContentView(R.layout.activity_search);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
SearchView searchView = (SearchView) menu.findItem(R.id.menu_search).getActionView();
searchView.setOnQueryTextListener(this);
return true;
}
//get entered search and pop up a toast to show query entered
public boolean onQueryTextSubmit (String query) {
//toast query
Toast.makeText(this, "Searching for: " + query + "...", Toast.LENGTH_SHORT).show();
//make json variables to fill
// url to make request
String url = "http://api.brewerydb.com/v2/search?key=myKey&format=json&type=beer&withBreweries=y&q=";
try {
query = URLEncoder.encode(query, "UTF-8");
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
String jsonUrl = url + query;
//todo: get json
new ReadJSONResult().execute(jsonUrl);
return false;
}
private class ReadJSONResult extends AsyncTask
<String, Void, String> {
protected String doInBackground(String... urls) {
return readJSONFeed(urls[0]);
}
protected void onPostExecute(String result) {
try {
//start progress bar
//requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
//setProgressBarIndeterminateVisibility(true);
///get
JSONObject json = new JSONObject(result);
//acces listview
lv = (ListView) findViewById(android.R.id.list);
//make array list for beer
final List<BeerData> beerList = new ArrayList<BeerData>();
//get json items
for(int i = 0; i < json.getJSONArray("data").length(); i++) {
String beerId = GetBeerDataFromJSON(i,"id", json);
String beerName = GetBeerDataFromJSON(i,"name", json);
String beerDescription = GetBeerDataFromJSON(i,"description" , json);
String beerAbv = GetBeerDataFromJSON(i,"abv" , json);
String beerIbu = GetBeerDataFromJSON(i,"ibu" , json);
String beerIcon = GetBeerIconsFromJSON(i, "icon",json );
String beerMediumIcon = GetBeerIconsFromJSON(i, "medium",json );
String beerLargeIcon = GetBeerIconsFromJSON(i, "large",json );
String beerGlass = GetBeerGlassFromJSON(i, json );
String beerStyle = GetBeerStyleFromJSON(i,"name", json );
String beerStyleDescription = GetBeerStyleFromJSON(i,"description", json );
String beerBreweryId = GetBeerBreweryInfoFromJSON(i, "id", json );
String beerBreweryName = GetBeerBreweryInfoFromJSON(i, "name", json );
String beerBreweryDescription = GetBeerBreweryInfoFromJSON(i, "description", json );
String beerBreweryWebsite = GetBeerBreweryInfoFromJSON(i, "website", json );
//get long and latt
String beerBreweryLat = GetBeerBreweryLocationJSON(i, "longitude", json );
String beerBreweryLong = GetBeerBreweryLocationJSON(i, "latitude", json );
String beerBreweryYear = GetBeerBreweryInfoFromJSON(i, "established", json );
String beerBreweryIcon = GetBeerBreweryIconsFromJSON(i,"large",json);
//create beer object
BeerData thisBeer = new BeerData(beerName, beerId, beerDescription, beerAbv, beerIbu, beerIcon,
beerMediumIcon,beerLargeIcon, beerGlass, beerStyle, beerStyleDescription, beerBreweryId, beerBreweryName,
beerBreweryDescription, beerBreweryYear, beerBreweryWebsite,beerBreweryIcon, beerBreweryLat, beerBreweryLong);
//add beer to list
beerList.add(thisBeer);
}
//update listview
BeerSearchAdapter adapter1 = new BeerSearchAdapter(Search.this ,R.layout.listview_item_row, beerList);
lv.setAdapter(adapter1);
//set up clicks
lv.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> arg0, View arg1,
int arg2, long arg3) {
Intent i = new Intent(Search.this, BeerPage.class);
BeerData beerInfo = beerList.get(arg2);
//Toast.makeText(MainActivity.this, beerInfo.beerName, Toast.LENGTH_SHORT).show();
i.putExtra("myBeerObject", beerInfo);
i.setClass(Search.this, BeerPage.class);
startActivity(i);
}
});
//end progress bar
//setProgressBarIndeterminateVisibility(false);
} catch (Exception e) {
Log.d("ReadBeerDataTask", e.getLocalizedMessage());
}
}
}
private String GetBeerDataFromJSON(int position, String whatToGet, JSONObject json ) {
String whatIsTheKeyYouAreLookFor = whatToGet;
int whereInTheJSONArrayForLoopIsTheData = position;
String holder = "";
try{
holder = json.getJSONArray("data").getJSONObject(whereInTheJSONArrayForLoopIsTheData).getString(whatIsTheKeyYouAreLookFor);
} catch (JSONException e) {
holder = "N/A";
}
return holder;
}
//get icons
private String GetBeerBreweryIconsFromJSON(int position, String whatToGet, JSONObject json ) {
String whatIsTheKeyYouAreLookFor = whatToGet;
int whereInTheJSONArrayForLoopIsTheData = position;
String holder = "";
try{
holder = json.getJSONArray("data").getJSONObject(whereInTheJSONArrayForLoopIsTheData).getJSONArray("breweries").getJSONObject(0).getJSONObject("images").getString(whatIsTheKeyYouAreLookFor);;
} catch (JSONException e) {
holder = "N/A";
}
return holder;
}
//get icons
private String GetBeerIconsFromJSON(int position, String whatToGet, JSONObject json ) {
String whatIsTheKeyYouAreLookFor = whatToGet;
int whereInTheJSONArrayForLoopIsTheData = position;
String holder = "";
try{
holder = json.getJSONArray("data").getJSONObject(whereInTheJSONArrayForLoopIsTheData).getJSONObject("labels").getString(whatIsTheKeyYouAreLookFor);
} catch (JSONException e) {
holder = "N/A";
}
return holder;
}
//get style information
private String GetBeerStyleFromJSON(int position, String whatToGet, JSONObject json ) {
String whatIsTheKeyYouAreLookFor = whatToGet;
int whereInTheJSONArrayForLoopIsTheData = position;
String holder = "";
try{
holder = json.getJSONArray("data").getJSONObject(whereInTheJSONArrayForLoopIsTheData).getJSONObject("style").getString(whatIsTheKeyYouAreLookFor);
} catch (JSONException e) {
holder = "N/A";
}
return holder;
}
//get location data
private String GetBeerBreweryLocationJSON(int position, String whatToGet, JSONObject json ) {
String whatIsTheKeyYouAreLookFor = whatToGet;
int whereInTheJSONArrayForLoopIsTheData = position;
String holder = "";
try{
holder = json.getJSONArray("data").getJSONObject(whereInTheJSONArrayForLoopIsTheData).getJSONArray("breweries").getJSONObject(0).getJSONArray("locations").getJSONObject(0).getString(whatIsTheKeyYouAreLookFor);
} catch (JSONException e) {
holder = "N/A";
}
return holder;
}
//get brewery information
//get style information
private String GetBeerBreweryInfoFromJSON(int position, String whatToGet, JSONObject json ) {
String whatIsTheKeyYouAreLookFor = whatToGet;
int whereInTheJSONArrayForLoopIsTheData = position;
String holder = "";
try{
holder = json.getJSONArray("data").getJSONObject(whereInTheJSONArrayForLoopIsTheData).getJSONArray("breweries").getJSONObject(0).getString(whatIsTheKeyYouAreLookFor);
} catch (JSONException e) {
holder = "N/A";
}
return holder;
}
//get glass
private String GetBeerGlassFromJSON(int position, JSONObject json ) {
int whereInTheJSONArrayForLoopIsTheData = position;
String holder = "";
try{
holder = json.getJSONArray("data").getJSONObject(whereInTheJSONArrayForLoopIsTheData).getJSONObject("glass").getString("name");
} catch (JSONException e) {
holder = "N/A";
}
return holder;
}
//gets the json from the inputed url
public String readJSONFeed(String URL) {
StringBuilder stringBuilder = new StringBuilder();
HttpClient httpClient = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(URL);
try {
HttpResponse response = httpClient.execute(httpGet);
StatusLine statusLine = response.getStatusLine();
int statusCode = statusLine.getStatusCode();
if (statusCode == 200) {
HttpEntity entity = response.getEntity();
InputStream inputStream = entity.getContent();
BufferedReader reader = new BufferedReader(
new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
stringBuilder.append(line);
}
inputStream.close();
} else {
Log.d("JSON", "Failed to download file");
}
} catch (Exception e) {
Log.d("readJSONFeed", e.getLocalizedMessage());
}
return stringBuilder.toString();
}
@Override
public boolean onQueryTextChange(String newText) {
// TODO Auto-generated method stub
return false;
}
}
答案 0 :(得分：3)
根据错误，beerList显然是List<BeerData>。您的构造函数不会使用List<BeerData>。它需要BeerData[]。转换适配器的构造函数，改为使用List<BeerData>。
答案 1 :(得分：0)
您可以改用
BeerSearchAdapter adapter1 = new BeerSearchAdapter(Search.this
,R.layout.listview_item_row, (BeerData[])beerList.toArray());
lv.setAdapter(adapter1);
答案 2 :(得分：0)
这将是未定义的，因为您将构造函数声明为此
BeerSearchAdapter(Context context, int layoutResourceId, BeerData[] data)