我是新的android和stackovrflow。我怎样才能使用Picasso所以我可以从我从他们的数据库url解析的json中加载电影图像？你能看看我的代码并告诉我我错过了什么吗？首先我使用虚拟图像，所以我可以填写我的gridview
private GridView gridview;
public ShowMoviesFragment() {
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
gridview = (GridView) rootView.findViewById(R.id.gridview);
gridview.setAdapter(new ImageAdapter(getContext()));
gridview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View v,
int position, long id) {
Toast.makeText(getContext(), "" + position,
Toast.LENGTH_SHORT).show();
}
});
return rootView;
}
private class ImageAdapter extends BaseAdapter {
private List<Item> items = new ArrayList<Item>();
private LayoutInflater inflater;
public ImageAdapter(Context context) {
inflater = LayoutInflater.from(context);
items.add(new Item("", R.drawable.sample_0));
items.add(new Item("", R.drawable.sample_1));
items.add(new Item("", R.drawable.sample_2));
items.add(new Item("", R.drawable.sample_3));
items.add(new Item("", R.drawable.sample_4));
items.add(new Item("", R.drawable.sample_5));
items.add(new Item("", R.drawable.sample_6));
items.add(new Item("", R.drawable.sample_7));
items.add(new Item("", R.drawable.zootopiaposter1));
items.add(new Item("", R.drawable.sample_4));
items.add(new Item("", R.drawable.sample_5));
items.add(new Item("", R.drawable.sample_6));
items.add(new Item("", R.drawable.sample_7));
}
@Override
public int getCount() {
return items.size();
}
@Override
public Object getItem(int i) {
return items.get(i);
}
@Override
public long getItemId(int i) {
return items.get(i).drawableId;
}
@Override
public View getView(int i, View view, ViewGroup viewGroup) {
View v = view;
ImageView picture;
TextView name;
if (v == null) {
v = inflater.inflate(R.layout.grid_view_item, viewGroup, false);
v.setTag(R.id.picture, v.findViewById(R.id.picture));
}
picture = (ImageView) v.getTag(R.id.picture);
Item item = (Item) getItem(i);
picture.setImageResource(item.drawableId);
return v;
}
private class Item {
final String name;
final int drawableId;
Item(String name, int drawableId) {
this.name = name;
this.drawableId = drawableId;
}
}
}
public class FetchMovieTask extends AsyncTask<String, Void, String[]> {
private final String LOG_TAG = FetchMovieTask.class.getSimpleName();
private String[] getPosterPathFromJson(String movieJsonStr) throws JSONException {
//These are the names of the JSON objects that need to be extracted.
final String TMDB_RESULTS = "results";
final String TMDB_TITLE = "original_title";
final String TMDB_OVERVIEW = "overview";
final String TMDB_RELEASE_DATE = "release_date";
final String TMDB_USER_RATING = "vote_average";
final String TMDB_POSTER = "poster_path";
JSONObject moviesDataJson = new JSONObject(movieJsonStr);
JSONArray moviesDataArray = moviesDataJson.getJSONArray(TMDB_RESULTS);
String[] posterPathStrs = new String[moviesDataArray.length()];
for (int i = 0; i < moviesDataArray.length(); i++) {
String poster_path;
poster_path = moviesDataJson.getString(TMDB_POSTER);
posterPathStrs[i] = poster_path;
}
for (String s : posterPathStrs) {
Log.v(LOG_TAG, "Poster Paths entry : " + s);
}
return posterPathStrs;
}
@Override
protected String[] doInBackground(String... params) {
// These two need to be declared outside the try/catch
// so that they can be closed in the finally block.
HttpURLConnection urlConnection = null;
BufferedReader reader = null;
// Will contain the raw JSON response as a string.
String movieDataJsonStr = null;
String format = "json";
try {
// Construct the URL for the TheMovieDatabase query
final String MOVIE_BASE_URL = "http://api.themoviedb.org/3/movie/popular?";
final String FORMAT_PARAM = "mode";
final String APPID_PARAM = "appid";
Uri builtUri = Uri.parse(MOVIE_BASE_URL).buildUpon()
.appendQueryParameter(FORMAT_PARAM, format)
.appendQueryParameter(APPID_PARAM, BuildConfig.THE_MOVIE_DATABASE_API_KEY)
.build();
URL url = new URL(builtUri.toString());
Log.v(LOG_TAG, "Build URI" + builtUri.toString());
// Create the request to OpenWeatherMap, and open the connection
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
// Read the input stream into a String
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if (inputStream == null) {
// Nothing to do.
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
// Since it's JSON, adding a newline isn't necessary (it won't affect parsing)
// But it does make debugging a *lot* easier if you print out the completed
// buffer for debugging.
buffer.append(line + "\n");
}
if (buffer.length() == 0) {
// Stream was empty. No point in parsing.
return null;
}
movieDataJsonStr = buffer.toString();
Log.v(LOG_TAG, "Movie Data JSON String:" + movieDataJsonStr);
} catch (IOException e) {
Log.e("PlaceholderFragment", "Error ", e);
// If the code didn't successfully get the weather data, there's no point in attemping
// to parse it.
return null;
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (final IOException e) {
Log.e("PlaceholderFragment", "Error closing stream", e);
}
}
}
try {
return getPosterPathFromJson(movieDataJsonStr);
} catch (JSONException e) {
Log.e(LOG_TAG, e.getMessage(), e);
e.printStackTrace();
}
return null;
}
@Override
protected void onProgressUpdate(Void... values) {
super.onProgressUpdate(values);
}
@Override
protected void onPostExecute(String[] result) {
for(String moviePath: result){
Picasso.with(getContext())
.load("http://image.tmdb.org/t/p/w185/result")
.into(gridview);
}
}
}
}
答案 0 :(得分：0)
您发布的代码有点大而复杂。 Picasso是一个可以从Urls中获取图像并将其显示在您的视图中的工具
这是一个小片段。
Picasso.with(aContext).load(imageUrl).into(yourImageView);