我有一个 android rate bar，它被膨胀成一个布局。当我运行代码时，我得到了我想从 json 更新 rateBar 的评级，然后我检查我的日志以查看我实际上得到了一个评级，我这样做了。但是当我尝试时：
RatingBar ratingBar = (RatingBar) ((Activity) c).findViewById(R.id.beerRatingBar);
ratingBar.setNumStars(beerRate);
它不会更新活动的 rateBar。
我的活动是啤酒页面：
public class BeerPage extends Activity {
BeerData e;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.beer_page);
//get data from listview
Intent intent = getIntent();
Bundle b = intent.getExtras();
e = b.getParcelable("myBeerObject");
//prepare buttons
Button buttonBrewery = (Button) findViewById(R.id.buttonBrewery);
Button buttonStyle = (Button) findViewById(R.id.buttonStyle);
//prepare text things
TextView tv1 = (TextView) findViewById(R.id.beerTitle);
TextView tv2 = (TextView) findViewById(R.id.beerDescription);
TextView tv_ibu = (TextView) findViewById(R.id.IBU);
TextView tv_abv = (TextView) findViewById(R.id.abv);
TextView tv_glass = (TextView) findViewById(R.id.glass);
//set text thinsg
tv1.setText(e.beerName);
tv2.setText(e.beerDescription);
buttonBrewery.setText(e.beerBreweryName);
buttonStyle.setText(e.beerStyle);
tv_ibu.setText(e.beerIBU);
tv_abv.setText(e.beerABV);
tv_glass.setText(e.beerGlass);
//Toast.makeText(this, e.mediumLabel, Toast.LENGTH_SHORT).show();
//set image
ImageView im1 = (ImageView) findViewById(R.id.image);
ImageDownloadTask imageD = new ImageDownloadTask(im1);
imageD.execute(e.largeLabel);
//test shared prefs
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
String userName = prefs.getString("userName", null);
String userID = prefs.getString("userID", null);
//check if user has beer
String url = myURL;
String userURLComp = user;
String beerID = beerID;
url = url + userURLComp + beerID;
Log.d("lat", e.beerBreweryLat);
Log.d("long", e.beerBreweryLong);
new CheckBeerJSON(this,e).execute(url);
}
//view brewery function
public void viewBrewery(View view) {
// launch new brewery page class
Intent i = new Intent(this, BreweryPage.class);
i.putExtra("myBeerObject", e);
i.setClass(this, BreweryPage.class);
startActivity(i);
}
public void viewStyle(View view) {
// launch new brewery page class
Intent i = new Intent(this, BreweryPage.class);
i.putExtra("myBeerObject", e);
i.setClass(this, StylePage.class);
startActivity(i);
}
public String encodeThisWord(String word){
try {
word = URLEncoder.encode(word, "UTF-8");
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return word;
}
public void addBeer(View view){
//get user info
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
String userName = prefs.getString("userName", null);
String userID = prefs.getString("userID", null);
//get beer details
String url = url2;
String urlUserID = userID;
String urlBeerID = beer + e.beerId;
String urlBeerName = beerName + encodeThisWord(e.beerName);
//construct url for adding beer
url = url + urlUserID + urlBeerID + urlBeerName;
Log.d("url", url);
//execute async on url to add to brewery
new AddBeer(this).execute(url);
//to do: change to start rater
}
}
GetUserRating 是我将评分放入 rateBar 的地方：
public class GetUserRating extends AsyncTask
<String, Void, String> {
Context c;
public GetUserRating(Context context)
{
c = context;
}
@Override
protected String doInBackground(String... arg0) {
// TODO Auto-generated method stub
return readJSONFeed(arg0[0]);
}
protected void onPostExecute(String result){
int beerRate = 0;
//parse json for value
try{
JSONObject json = new JSONObject(result);
beerRate = json.getInt("rate");
}
catch(Exception e){
}
Log.d("logIN", "the rating: " + beerRate);
//change rating
RatingBar ratingBar = (RatingBar) ((Activity) c).findViewById(R.id.beerRatingBar);
ratingBar.setNumStars(beerRate);
}
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();
}
}