在 android 中的图像适配器中本地保存图像
Save Images locally in Image adapter in android
这是一个关于 android 应用程序中图像保存的问题。
我正在尝试制作一个大胆的流行电影应用程序 project.Link - https://docs.google.com/document/d/1gtXUu1nzLGWrGfVCD6tEA0YHoYA9UNyT2yByqjJemp8/pub?embedded=true
我在 ImageAdapter 中有用于图片下载的 picasso 库--
这是我的 ImageAdapter 代码 -
package jindal5.mayank.popular_movies_14ce10032_gsc;
public class ImageAdapter extends BaseAdapter {
private String drawablePrefix;
private Context mContext;
private ArrayList<String> mThumbUris;
private ArrayList<String> mov_id_arr;
private ArrayList<String> mov_tit_arr;
public ImageAdapter(Context c) {
mContext = c;
String packName=mContext.getPackageName();
drawablePrefix="android.resource://" +packName+ "/";
ArrayList<String> mov_id_arr =new ArrayList<>();
ArrayList<String> mov_tit_arr=new ArrayList<>();
mov_tit_arr.add("asdf");
mov_tit_arr.add("asdf");
mov_tit_arr.add("asdf");
mov_tit_arr.add("asdf");
mov_tit_arr.add("asdf");
mov_tit_arr.add("asdf");
ArrayList<String> uriPaths=new ArrayList<>();// place your drawables.
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
mThumbUris=uriPaths;
}
public int getCount() {
return mThumbUris.size();
}
public Object getItem(int position) {
return mThumbUris.get(position);
}
public long getItemId(int position) {
return 0;
}
// create a new ImageView for each item referenced by the Adapter
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView;
if (convertView == null) {
// if it's not recycled, initialize some attributes
imageView = new ImageView(mContext);
// imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
// imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
// imageView.setPadding(8, 8, 8, 8);
} else {
imageView = (ImageView) convertView;
}
Uri imgUri=Uri.parse(mThumbUris.get(position));
Picasso.with(mContext)
.load(imgUri)
.placeholder(R.drawable.sample_0)
.centerCrop()
.resize(400,400)
.into(imageView);
imageView.setImageResource(mThumbIds[position]);
// imageView.setAdjustViewBounds(true);
return imageView;
}
public ArrayList<String> getUriList(){
return mThumbUris;
}
public ArrayList<String> getidlist(){
return mov_id_arr;
}
public ArrayList<String> gettitlist(){
return mov_tit_arr;
}
// references to our images
private Integer[] mThumbIds = {
R.drawable.sample_2, R.drawable.sample_3,
R.drawable.sample_4, R.drawable.sample_5,
R.drawable.sample_6, R.drawable.sample_7,
R.drawable.sample_0, R.drawable.sample_1,
R.drawable.sample_2, R.drawable.sample_3,
R.drawable.sample_4, R.drawable.sample_5,
R.drawable.sample_6, R.drawable.sample_7,
R.drawable.sample_0, R.drawable.sample_1,
R.drawable.sample_2, R.drawable.sample_3,
R.drawable.sample_4, R.drawable.sample_5,
R.drawable.sample_6, R.drawable.sample_7
};
}
现在我有两个问题-
- 当我 return 从另一个 activity 返回 Main Activity 时，出现本地图像而不是之前下载的图像。
- 当我关闭我的应用程序并再次打开时，我看到出现的是本地图像，而不是上次下载的图像。有人告诉您必须在使用文件或内容提供程序将图像下载到本地内存后保存这些图像。但我不知道该怎么做？？ .
3.When 我改变了我的设备方向我遇到了同样的问题。
这是我的主要片段activity-
package jindal5.mayank.popular_movies_14ce10032_gsc;
/**
* A placeholder fragment containing a simple view.
*/
public class MainActivityFragment extends Fragment {
public ImageAdapter imag_adap;
public String movieJsonStr;
public ArrayList<String > tit_arr = new ArrayList<String>();
public ArrayList<String > rel_dat_arr = new ArrayList<String>();
public ArrayList<String > url1_arr = new ArrayList<String>();
public ArrayList<String > over_arr = new ArrayList<String>();
public ArrayList<String > id_arr = new ArrayList<String>();
public String put_ext_tit;
public String rel_date_ext;
public String url_for_pos_ex;
public String over_ex;
public String id_ex;
public MainActivityFragment() {
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Add this line in order for this fragment to handle menu events.
setHasOptionsMenu(true);
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.menu_fragment, menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_refresh) {
//SharedPreferences share = PreferenceManager.getDefaultSharedPreferences();
// String order = share.getString()
getimage imageTask = new getimage();
imageTask.execute("popularity.desc");
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootview = inflater.inflate(R.layout.fragment_main, container, false);
GridView grid = (GridView) rootview.findViewById(R.id.gridView);
imag_adap = new ImageAdapter(getActivity());
grid.setAdapter(imag_adap);
grid.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
String[] tit1 = tit_arr.toArray(new String[tit_arr.size()]);
String[] rel_date = rel_dat_arr.toArray(new String[rel_dat_arr.size()]);
String[] url_for_pos = url1_arr.toArray(new String[url1_arr.size()]);
String[] over = url1_arr.toArray(new String[over_arr.size()]);
String[] id = id_arr.toArray(new String[over_arr.size()]);
// Log.v("mayank",tit1[3]);
try{
put_ext_tit = tit1[i];
rel_date_ext = rel_date[i];
url_for_pos_ex = url_for_pos[i];
over_ex = over[i];
id_ex =id[i];
Intent intent = new Intent(getActivity(),det_mov.class);
//.putExtra(Intent.EXTRA_TEXT,put_ext_tit);
Bundle extras = new Bundle();
extras.putString("title",put_ext_tit);
extras.putString("rel_date",rel_date_ext);
extras.putString("url_pos",url_for_pos_ex);
extras.putString("over_ex",over_ex);
extras.putString("id_ex", id_ex);
extras.putInt("posit",i);
intent.putExtras(extras);
startActivity(intent);
}
catch (ArrayIndexOutOfBoundsException p){
Log.e("mayank","reg",p);
}
}
});
return rootview;
}
public class getimage extends AsyncTask<String, String, String[]> {
ConnectivityManager conMgr = (ConnectivityManager) getActivity().getSystemService(Context.CONNECTIVITY_SERVICE);
private final String LOG_TAG = getimage.class.getSimpleName();
public int count;
String[] pos_path;
String[] mov_id;
String[] tit;
String[] rev;
String[] rel_dat;
String[] url1;
String[] over;
String[] id;
public ImageAdapter getad(){
return imag_adap;
}
@Override
protected String[] doInBackground(String... params) {
HttpURLConnection urlConnection = null;
BufferedReader reader = null;
try {
final String movie_url_str = "http://api.themoviedb.org/3/discover/movie?sort_by="+ params[0] +"&api_key=8d7a48043ba1d3348181e2b6615cedc7";
URL movie_url = new URL(movie_url_str);
urlConnection = (HttpURLConnection) movie_url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if (inputStream == null) {
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
buffer.append(line + "\n");
}
if (buffer.length() == 0) {
return null;
}
movieJsonStr = buffer.toString();
JSONObject movieJson = new JSONObject(movieJsonStr);
JSONArray movieJsonarray = movieJson.getJSONArray("results");
count = movieJsonarray.length();
pos_path = new String[count];
mov_id = new String[count];
tit = new String[count];
rev = new String[count];
rel_dat = new String[count];
url1 = new String[count];
over = new String[count];
id = new String[count];
for(int i=0;i<count;i++){
JSONObject sin_movie = movieJsonarray.getJSONObject(i);
pos_path[i] = sin_movie.getString("poster_path");
over[i] = sin_movie.getString("overview");
Uri.Builder url_for_poster = new Uri.Builder();
String qw = "t";
String as = "p";
Uri.Builder url_build = url_for_poster.scheme("http").authority("image.tmdb.org").appendPath(qw).appendPath(as).appendPath("w500").appendEncodedPath(pos_path[i]);
url1[i] = url_build.toString();
// mov_id[i] = sin_movie.getString("id");
tit[i] = sin_movie.getString("title");
//rev[i] = sin_movie.getString("review");
rel_dat[i] = sin_movie.getString("release_date");
id[i] = sin_movie.getString("id");
publishProgress((String)(tit[i]),(String)(rel_dat[i]),(String)(url1[i]),(String)(over[i]),(String)(id[i]));
Log.v(LOG_TAG, "Forecast string: " + id[i]);
}
} catch (IOException | JSONException e) {
Log.e(LOG_TAG, "Error ", e);
return null;
}
finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (final IOException e) {
Log.e(LOG_TAG, "Error closing stream", e);
}
}
}
return pos_path;
}
@Override
protected void onProgressUpdate(String... values) {
tit_arr.add(values[0]);
rel_dat_arr.add(values[1]);
url1_arr.add(values[2]);
over_arr.add(values[3]);
id_arr.add(values[4]);
}
@Override
protected void onPostExecute(String[] result) {
ArrayList<String> uriPaths = imag_adap.getUriList();
uriPaths.clear();
// ImageView[] im_vi = new ImageView[count];
for(int j=0;j<count;j++) {
String pos_sin_path = pos_path[j];
String id_mov = id[j];
Uri.Builder url_for_poster = new Uri.Builder();
Uri.Builder url_for_rev = new Uri.Builder();
String qw = "t";
String as = "p";
Uri.Builder url_build = url_for_poster.scheme("http").authority("image.tmdb.org").appendPath(qw).appendPath(as).appendPath("w500").appendEncodedPath(pos_sin_path);
String url = url_build.toString();
Uri.Builder url_build_rev = url_for_rev.scheme("http").encodedAuthority("api.themoviedb.org/3/movie").appendPath(id_mov).appendPath("reviews");
uriPaths.add(url);
// mov_title.add(tit[j]);
//mov_id_arr.add(id);
// mov_tit_arr.add(title);
// }
//catch (UnsupportedEncodingException e){
//}
//url_build.clearQuery();
//Picasso.with(getActivity()).load("http://image.tmdb.org/t/p/w185//nBNZadXqJSdt05SHLqgT0HuC5Gm.jpg").into(im_vi[j]);
//imag_adap.getItem(j) = im_vi[j];\
}
imag_adap.notifyDataSetChanged();
}
}
}
寻求帮助因为我是 android 的新人。
试试这个，
answer-1:
尝试将onCreateView 的适配器初始化逻辑更改为onCreate。
将此行放在 onCreate.
imag_adap = new ImageAdapter(getActivity());
answer-2:
下载图像后，将 uri 路径保存在数据库或文件或共享首选项中。然后在创建适配器中检索该 uri。
ArrayList<String> uriPathsFromDb=getListOfUriFromDatabase();
if(uriPathsFromDb.size()==0){
ArrayList<String> uriPaths=new ArrayList<>();// place your drawables.
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
mThumbUris=uriPaths;
}else{
mThumbUris=uriPathsFromDb;
}
When I close my app and open again I see the local images appear rather than downloaded images at last time. Somebody told that you have to save that images after downloading in local memory using File or content provider. But I don't know how to do that ?? .
这是预料之中的，因为您 device.Save 数据库 (SQLite) 中的图像中的任何地方都没有照片 如果您希望它在您 return 到您的应用程序时保留并可用。或者每次重启 activity 时加载它们，最好通过 AsyncTask。
要将图像存储在 SQLite 数据库中，请查看 How to store(bitmap image) and retrieve image from sqlite database in android? 告诉您有关保存和检索图像的所有信息。
这是一个关于 android 应用程序中图像保存的问题。 我正在尝试制作一个大胆的流行电影应用程序 project.Link - https://docs.google.com/document/d/1gtXUu1nzLGWrGfVCD6tEA0YHoYA9UNyT2yByqjJemp8/pub?embedded=true
我在 ImageAdapter 中有用于图片下载的 picasso 库--
这是我的 ImageAdapter 代码 -
package jindal5.mayank.popular_movies_14ce10032_gsc;
public class ImageAdapter extends BaseAdapter {
private String drawablePrefix;
private Context mContext;
private ArrayList<String> mThumbUris;
private ArrayList<String> mov_id_arr;
private ArrayList<String> mov_tit_arr;
public ImageAdapter(Context c) {
mContext = c;
String packName=mContext.getPackageName();
drawablePrefix="android.resource://" +packName+ "/";
ArrayList<String> mov_id_arr =new ArrayList<>();
ArrayList<String> mov_tit_arr=new ArrayList<>();
mov_tit_arr.add("asdf");
mov_tit_arr.add("asdf");
mov_tit_arr.add("asdf");
mov_tit_arr.add("asdf");
mov_tit_arr.add("asdf");
mov_tit_arr.add("asdf");
ArrayList<String> uriPaths=new ArrayList<>();// place your drawables.
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
mThumbUris=uriPaths;
}
public int getCount() {
return mThumbUris.size();
}
public Object getItem(int position) {
return mThumbUris.get(position);
}
public long getItemId(int position) {
return 0;
}
// create a new ImageView for each item referenced by the Adapter
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView;
if (convertView == null) {
// if it's not recycled, initialize some attributes
imageView = new ImageView(mContext);
// imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
// imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
// imageView.setPadding(8, 8, 8, 8);
} else {
imageView = (ImageView) convertView;
}
Uri imgUri=Uri.parse(mThumbUris.get(position));
Picasso.with(mContext)
.load(imgUri)
.placeholder(R.drawable.sample_0)
.centerCrop()
.resize(400,400)
.into(imageView);
imageView.setImageResource(mThumbIds[position]);
// imageView.setAdjustViewBounds(true);
return imageView;
}
public ArrayList<String> getUriList(){
return mThumbUris;
}
public ArrayList<String> getidlist(){
return mov_id_arr;
}
public ArrayList<String> gettitlist(){
return mov_tit_arr;
}
// references to our images
private Integer[] mThumbIds = {
R.drawable.sample_2, R.drawable.sample_3,
R.drawable.sample_4, R.drawable.sample_5,
R.drawable.sample_6, R.drawable.sample_7,
R.drawable.sample_0, R.drawable.sample_1,
R.drawable.sample_2, R.drawable.sample_3,
R.drawable.sample_4, R.drawable.sample_5,
R.drawable.sample_6, R.drawable.sample_7,
R.drawable.sample_0, R.drawable.sample_1,
R.drawable.sample_2, R.drawable.sample_3,
R.drawable.sample_4, R.drawable.sample_5,
R.drawable.sample_6, R.drawable.sample_7
};
}
现在我有两个问题-
- 当我 return 从另一个 activity 返回 Main Activity 时，出现本地图像而不是之前下载的图像。
- 当我关闭我的应用程序并再次打开时，我看到出现的是本地图像，而不是上次下载的图像。有人告诉您必须在使用文件或内容提供程序将图像下载到本地内存后保存这些图像。但我不知道该怎么做？？ .
3.When 我改变了我的设备方向我遇到了同样的问题。
这是我的主要片段activity-
package jindal5.mayank.popular_movies_14ce10032_gsc;
/**
* A placeholder fragment containing a simple view.
*/
public class MainActivityFragment extends Fragment {
public ImageAdapter imag_adap;
public String movieJsonStr;
public ArrayList<String > tit_arr = new ArrayList<String>();
public ArrayList<String > rel_dat_arr = new ArrayList<String>();
public ArrayList<String > url1_arr = new ArrayList<String>();
public ArrayList<String > over_arr = new ArrayList<String>();
public ArrayList<String > id_arr = new ArrayList<String>();
public String put_ext_tit;
public String rel_date_ext;
public String url_for_pos_ex;
public String over_ex;
public String id_ex;
public MainActivityFragment() {
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Add this line in order for this fragment to handle menu events.
setHasOptionsMenu(true);
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.menu_fragment, menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_refresh) {
//SharedPreferences share = PreferenceManager.getDefaultSharedPreferences();
// String order = share.getString()
getimage imageTask = new getimage();
imageTask.execute("popularity.desc");
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootview = inflater.inflate(R.layout.fragment_main, container, false);
GridView grid = (GridView) rootview.findViewById(R.id.gridView);
imag_adap = new ImageAdapter(getActivity());
grid.setAdapter(imag_adap);
grid.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
String[] tit1 = tit_arr.toArray(new String[tit_arr.size()]);
String[] rel_date = rel_dat_arr.toArray(new String[rel_dat_arr.size()]);
String[] url_for_pos = url1_arr.toArray(new String[url1_arr.size()]);
String[] over = url1_arr.toArray(new String[over_arr.size()]);
String[] id = id_arr.toArray(new String[over_arr.size()]);
// Log.v("mayank",tit1[3]);
try{
put_ext_tit = tit1[i];
rel_date_ext = rel_date[i];
url_for_pos_ex = url_for_pos[i];
over_ex = over[i];
id_ex =id[i];
Intent intent = new Intent(getActivity(),det_mov.class);
//.putExtra(Intent.EXTRA_TEXT,put_ext_tit);
Bundle extras = new Bundle();
extras.putString("title",put_ext_tit);
extras.putString("rel_date",rel_date_ext);
extras.putString("url_pos",url_for_pos_ex);
extras.putString("over_ex",over_ex);
extras.putString("id_ex", id_ex);
extras.putInt("posit",i);
intent.putExtras(extras);
startActivity(intent);
}
catch (ArrayIndexOutOfBoundsException p){
Log.e("mayank","reg",p);
}
}
});
return rootview;
}
public class getimage extends AsyncTask<String, String, String[]> {
ConnectivityManager conMgr = (ConnectivityManager) getActivity().getSystemService(Context.CONNECTIVITY_SERVICE);
private final String LOG_TAG = getimage.class.getSimpleName();
public int count;
String[] pos_path;
String[] mov_id;
String[] tit;
String[] rev;
String[] rel_dat;
String[] url1;
String[] over;
String[] id;
public ImageAdapter getad(){
return imag_adap;
}
@Override
protected String[] doInBackground(String... params) {
HttpURLConnection urlConnection = null;
BufferedReader reader = null;
try {
final String movie_url_str = "http://api.themoviedb.org/3/discover/movie?sort_by="+ params[0] +"&api_key=8d7a48043ba1d3348181e2b6615cedc7";
URL movie_url = new URL(movie_url_str);
urlConnection = (HttpURLConnection) movie_url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if (inputStream == null) {
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
buffer.append(line + "\n");
}
if (buffer.length() == 0) {
return null;
}
movieJsonStr = buffer.toString();
JSONObject movieJson = new JSONObject(movieJsonStr);
JSONArray movieJsonarray = movieJson.getJSONArray("results");
count = movieJsonarray.length();
pos_path = new String[count];
mov_id = new String[count];
tit = new String[count];
rev = new String[count];
rel_dat = new String[count];
url1 = new String[count];
over = new String[count];
id = new String[count];
for(int i=0;i<count;i++){
JSONObject sin_movie = movieJsonarray.getJSONObject(i);
pos_path[i] = sin_movie.getString("poster_path");
over[i] = sin_movie.getString("overview");
Uri.Builder url_for_poster = new Uri.Builder();
String qw = "t";
String as = "p";
Uri.Builder url_build = url_for_poster.scheme("http").authority("image.tmdb.org").appendPath(qw).appendPath(as).appendPath("w500").appendEncodedPath(pos_path[i]);
url1[i] = url_build.toString();
// mov_id[i] = sin_movie.getString("id");
tit[i] = sin_movie.getString("title");
//rev[i] = sin_movie.getString("review");
rel_dat[i] = sin_movie.getString("release_date");
id[i] = sin_movie.getString("id");
publishProgress((String)(tit[i]),(String)(rel_dat[i]),(String)(url1[i]),(String)(over[i]),(String)(id[i]));
Log.v(LOG_TAG, "Forecast string: " + id[i]);
}
} catch (IOException | JSONException e) {
Log.e(LOG_TAG, "Error ", e);
return null;
}
finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (final IOException e) {
Log.e(LOG_TAG, "Error closing stream", e);
}
}
}
return pos_path;
}
@Override
protected void onProgressUpdate(String... values) {
tit_arr.add(values[0]);
rel_dat_arr.add(values[1]);
url1_arr.add(values[2]);
over_arr.add(values[3]);
id_arr.add(values[4]);
}
@Override
protected void onPostExecute(String[] result) {
ArrayList<String> uriPaths = imag_adap.getUriList();
uriPaths.clear();
// ImageView[] im_vi = new ImageView[count];
for(int j=0;j<count;j++) {
String pos_sin_path = pos_path[j];
String id_mov = id[j];
Uri.Builder url_for_poster = new Uri.Builder();
Uri.Builder url_for_rev = new Uri.Builder();
String qw = "t";
String as = "p";
Uri.Builder url_build = url_for_poster.scheme("http").authority("image.tmdb.org").appendPath(qw).appendPath(as).appendPath("w500").appendEncodedPath(pos_sin_path);
String url = url_build.toString();
Uri.Builder url_build_rev = url_for_rev.scheme("http").encodedAuthority("api.themoviedb.org/3/movie").appendPath(id_mov).appendPath("reviews");
uriPaths.add(url);
// mov_title.add(tit[j]);
//mov_id_arr.add(id);
// mov_tit_arr.add(title);
// }
//catch (UnsupportedEncodingException e){
//}
//url_build.clearQuery();
//Picasso.with(getActivity()).load("http://image.tmdb.org/t/p/w185//nBNZadXqJSdt05SHLqgT0HuC5Gm.jpg").into(im_vi[j]);
//imag_adap.getItem(j) = im_vi[j];\
}
imag_adap.notifyDataSetChanged();
}
}
}
寻求帮助因为我是 android 的新人。
试试这个，
answer-1:
尝试将onCreateView 的适配器初始化逻辑更改为onCreate。 将此行放在 onCreate.
imag_adap = new ImageAdapter(getActivity());
answer-2:
下载图像后，将 uri 路径保存在数据库或文件或共享首选项中。然后在创建适配器中检索该 uri。
ArrayList<String> uriPathsFromDb=getListOfUriFromDatabase();
if(uriPathsFromDb.size()==0){
ArrayList<String> uriPaths=new ArrayList<>();// place your drawables.
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
uriPaths.add(drawablePrefix+ R.drawable.sample_0);
mThumbUris=uriPaths;
}else{
mThumbUris=uriPathsFromDb;
}
When I close my app and open again I see the local images appear rather than downloaded images at last time. Somebody told that you have to save that images after downloading in local memory using File or content provider. But I don't know how to do that ?? .
这是预料之中的，因为您 device.Save 数据库 (SQLite) 中的图像中的任何地方都没有照片 如果您希望它在您 return 到您的应用程序时保留并可用。或者每次重启 activity 时加载它们，最好通过 AsyncTask。
要将图像存储在 SQLite 数据库中，请查看 How to store(bitmap image) and retrieve image from sqlite database in android? 告诉您有关保存和检索图像的所有信息。