下载图像并保存在图库中？
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【中文标题】下载图像并保存在图库中？【英文标题】：download image and save in gallery? 【发布时间】：2015-04-19 00:39:01 【问题描述】：我从服务器得到响应，在我的响应中我得到图像，该响应的视图在列表视图中，现在我想要的是下面的图像我有一个下载图像的按钮，我想下载该图像和将其存储在图库中。下面是我的代码和响应。
JSON 响应..
[
"b_card":"http:\/\/www.webname.com\/uploaded\/users\/vcard\/8_ers.jpg"
]
MyBaseAdapter
public class CustomAdapterBusinessCard extends BaseAdapter
private static Bitmap bmp;
private Context context;
private ArrayList<HashMap<String,String>> listData;
private AQuery aQuery;
/*private static final String ADD_NAME="title_tag";
private static final String ADD_DESC="description";*/
private static final String ADD_IMAGE="b_card";
public CustomAdapterBusinessCard(Context context,ArrayList<HashMap<String,String>> listData)
this.context = context;
this.listData=listData;
aQuery = new AQuery(this.context);
@Override
public int getCount()
return listData.size();
@Override
public Object getItem(int position)
return listData.get(position);
@Override
public long getItemId(int position)
return position;
@Override
public View getView(final int position, View convertView, ViewGroup parent)
ViewHolder holder;
if (convertView == null)
holder = new ViewHolder();
convertView = LayoutInflater.from(context).inflate(R.layout.business_card, null);
holder.propic = (ImageView) convertView.findViewById(R.id.imgvwbusinesscard);
holder.btndownload=(Button) convertView.findViewById(R.id.dwnldbutton);
// holder.txtproname = (TextView) convertView.findViewById(R.id.txtproducts);
// holder.txtproid = (TextView) convertView.findViewById(R.id.txtproidsearch);
//holder.txtprofilecast = (TextView) convertView.findViewById(R.id.txtproductsdescription);
holder.btndownload.setOnClickListener(new OnClickListener()
private String url;
@Override
public void onClick(View v)
url = listData.get(position).get("b_card");
System.out.println("cheking url"+url);
new DownloadImageAsyncTask().execute();
/*try
bmp = getBitmapFromUrl(url);
catch (IOException e)
// TODO Auto-generated catch block
e.printStackTrace();
*/
);
convertView.setTag(holder);
else
holder = (ViewHolder) convertView.getTag();
/* holder.txtproname.setText(listData.get(position).get(ADD_NAME));
//holder.txtproid.setText(listData.get(position).get(TAG_PROFILE));
holder.txtprofilecast.setText(listData.get(position).get(ADD_DESC));
*/
holder.propic.setImageDrawable(Drawable.createFromPath(context.getExternalCacheDir() + File.separator
+ context.getResources().getString(R.string.app_name) + File.separator + "ImageName.png"));
aQuery.id(holder.propic).image(listData.get(position).get(ADD_IMAGE),true,true,0,R.drawable.ic_launcher);
// image parameter : 1 : memory cache,2:file cache,3:target width,4:fallback image
return convertView;
class ViewHolder
ImageView propic;
Button btndownload;
// TextView txtproname;
// TextView txtproid;
// TextView txtprofilecast;
class DownloadImageAsyncTask extends AsyncTask<Void, Void, Void>
@Override
protected Void doInBackground(Void... params)
// TODO Auto-generated method stub
downloadImages();
return null;
@Override
protected void onPostExecute(Void result)
// TODO Auto-generated method stub
super.onPostExecute(result);
private void downloadImages()
URL imageUrl; //your URL from which image to be downloaded
String domain;
try
imageUrl = new URL("http://www.webname.com/web-service/b_card.php?user_id=8");
HttpURLConnection urlConnection;
try
urlConnection = (HttpURLConnection) imageUrl.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.connect();
String path = context.getExternalCacheDir() + File.separator + context.getResources().getString(R.string.app_name);
File f = new File(path);
if (!f.exists())
f.mkdirs();
File file = new File(f, "ImageName.png"); // Here you can save the image with name and extension
if (!file.exists())
file.createNewFile();
FileOutputStream fileOutput = new FileOutputStream(file);
InputStream inputStream = urlConnection.getInputStream();
byte[] buffer = new byte[1024];
int bufferLength = 0; // used to store a temporary size of the
// buffer
while ((bufferLength = inputStream.read(buffer)) > 0)
fileOutput.write(buffer, 0, bufferLength);
fileOutput.close();
catch (IOException e)
e.printStackTrace();
catch (MalformedURLException e)
e.printStackTrace();
我的活动
public class BusinessCard extends ListActivity
private ArrayList<HashMap<String,String>> aList;
private String User_id;
JSONArray country_list=null;
private CustomAdapterBusinessCard adapter;
private ImageView bucard;
ImageLoader _DownImageLoader;
AQuery androidAQuery=new AQuery(this);
JSONArray state_list=null;
private static String BUSINESS_CARD_URL = "";
private static final String BUSINESS_CARD="b_card";
ArrayList<HashMap<String,String>> subcatagorydata;
@Override
protected void onCreate(Bundle savedInstanceState)
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.list_view_businesscard);
User_id=this.getIntent().getStringExtra("userids");
System.out.println("for business card"+User_id);
BUSINESS_CARD_URL="http://www.webname.com/web-service/b_card.php?user_id="+User_id;
bucard=(ImageView)findViewById(R.id.imgvwbusinesscard);
new LoadBusiness().execute();
class LoadBusiness extends AsyncTask<String, String, ArrayList<HashMap<String,String>>>
ArrayAdapter<String> adaptercountry ;
private ProgressDialog pDialog;
private ArrayList<HashMap<String, String>> data;
private String desc;
@Override
protected void onPreExecute()
super.onPreExecute();
pDialog = new ProgressDialog(BusinessCard.this);
pDialog.setMessage("Loading...");
pDialog.setIndeterminate(false);
// pDialog.setIndeterminateDrawable(getResources().getDrawable(R.drawable.custom_progress));
pDialog.setCancelable(true);
pDialog.show();
protected ArrayList<HashMap<String,String>> doInBackground(String... args)
ServiceHandler sh = new ServiceHandler();
// Making a request to url and getting response
data = new ArrayList<HashMap<String, String>>();
String jsonStr = sh.makeServiceCall(BUSINESS_CARD_URL, ServiceHandler.GET);
Log.d("Response: ", "> " + jsonStr);
if (jsonStr != null)
try
//JSONObject jsonObj = new JSONObject(jsonStr);
// Getting JSON Array node
//JSONArray data_array = new JSONArray(received);
country_list = new JSONArray(jsonStr);
// looping through All Contacts
for (int i = 0; i < country_list.length(); i++)
JSONObject c = country_list.getJSONObject(i);
// creating new HashMap
HashMap<String, String> map = new HashMap<String, String>();
// adding each child node to HashMap key => value
map.put(BUSINESS_CARD, c.getString(BUSINESS_CARD));
/*map.put(PROFILE_VIEW_SUB_CATAGORY,c.getString(PROFILE_VIEW_SUB_CATAGORY));
map.put(PROFILE_VIEW_IMAGE,c.getString(PROFILE_VIEW_IMAGE));*/
// desc=country_list.getJSONObject(0).getJSONObject("description").toString();
/*JSONObject js=new JSONObject();
js.getString("description");
desc=js.toString();*/
// System.out.println("jsjsj"+desc);
data.add(map);
catch (JSONException e)
e.printStackTrace();
else
Log.e("ServiceHandler", "Couldn't get any data from the url");
return data;
protected void onPostExecute(ArrayList<HashMap<String,String>> result)
super.onPostExecute(result);
pDialog.dismiss();
if(aList == null)
aList = new ArrayList<HashMap<String, String>>();
aList.addAll(result);
adapter = new CustomAdapterBusinessCard(getBaseContext(), result);
setListAdapter(adapter);
else
aList.addAll(result);
adapter.notifyDataSetChanged();
列表视图
<RelativeLayout
android:layout_
android:layout_
android:background="@android:color/white"
>
<ListView
android:layout_
android:layout_
android:id="@android:id/list"
android:dividerHeight="1dp"
></ListView>
</RelativeLayout>
列表项
<LinearLayout
android:layout_
android:layout_
android:orientation="vertical" >
<ImageView
android:layout_
android:layout_
android:id="@+id/imgvwbusinesscard"
/>
<Button
android:layout_
android:layout_
android:text="Download"
android:id="@+id/dwnldbutton"
/>
</LinearLayout>
【问题讨论】：
保存图像使用此代码***.com/a/7887114/964741 我可以在我的基本适配器文件或活动中在哪里使用该功能？首先我需要下载然后想要存储 您要存储图像的位置...一旦从 url 下载图像，就会将位图传递给该函数。它将保存该图像。 我想将它存储在画廊中。我应该将该功能添加到我的基本适配器的 btn clikc 列表器中吗？ 是的.. 图像下载完成后调用它 【参考方案1】：我通过使用 AsyncTask 从 URL 下载图像来做到这一点。
class DownloadImageAsyncTask extends AsyncTask<Void, Void, Void>
@Override
protected Void doInBackground(Void... params)
// TODO Auto-generated method stub
downloadImages();
return null;
@Override
protected void onPostExecute(Void result)
// TODO Auto-generated method stub
super.onPostExecute(result);
这是下载图片的功能，你可以从很多网站得到参考。
private void downloadImages()
URL imageUrl; //your URL from which image to be downloaded
String domain;
try
imageUrl = new URL("your URL");
HttpURLConnection urlConnection;
try
urlConnection = (HttpURLConnection) imageUrl.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.connect();
String path = getExternalCacheDir() + File.separator + getResources().getString(R.string.app_name);
File f = new File(path);
if (!f.exists())
f.mkdirs();
File file = new File(f, "ImageName.png"); // Here you can save the image with name and extension
if (!file.exists())
file.createNewFile();
FileOutputStream fileOutput = new FileOutputStream(file);
InputStream inputStream = urlConnection.getInputStream();
byte[] buffer = new byte[1024];
int bufferLength = 0; // used to store a temporary size of the
// buffer
while ((bufferLength = inputStream.read(buffer)) > 0)
fileOutput.write(buffer, 0, bufferLength);
fileOutput.close();
catch (IOException e)
e.printStackTrace();
catch (MalformedURLException e)
e.printStackTrace();
然后在您的 Adapter 类中，您可以通过以下方式设置图像：
holder.propic.setImageDrawable(Drawable.createFromPath(getExternalCacheDir() + File.separator
+ getResources().getString(R.string.app_name) + File.separator + "ImageName.png")); //Exact path where the image is saved.
希望对你有帮助。
【讨论】：
好的..当第一次运行应用程序时..按钮消失并且图像显示一半..然后按返回按钮..再次加载该页面..然后按钮出现并且图像消失了。 .and in logcat..java.net.MalformedURLException: Protocol not found: your URL 如何设置 holder.propic.setImageDrawable(Drawable.createFromPath(context.getExternalCacheDir() + File.separator + context.getResources().getString(R.string.app_name) + File.separator + "ImageName.png"));在下载图像之前？ 在不下载图片之前设置默认图片，点击下载按钮后设置下载的图片。 现在两者都正确显示，但是..仍然在 logcat 中显示 java.net.MalformedURLException: Protocol not found: your URL ..我该怎么办？你能推荐一下兄弟吗？ 请先学习基础知识.. imageUrl = new URL("your URL");.... 您必须在"位置添加要从中下载图像的图像URL你的网址”【参考方案2】：使用此代码从 URL 下载图像
public Bitmap getBitmapFromURL(String src)
try
java.net.URL url = new java.net.URL(src);
HttpURLConnection connection = (HttpURLConnection) url
.openConnection();
connection.setDoInput(true);
connection.connect();
InputStream input = connection.getInputStream();
Bitmap myBitmap = BitmapFactory.decodeStream(input);
return myBitmap;
catch (IOException e)
e.printStackTrace();
return null;
【讨论】：
【参考方案3】：使用以下代码从url下载图片：
private static Bitmap getBitmapFromUrl(String imgURL)
throws IOException
URL IMGURL = new URL(imgURL);
HttpURLConnection conn = (HttpURLConnection) IMGURL.openConnection();
conn.setDoInput(true);
conn.connect();
conn.setConnectTimeout(30000);
conn.setReadTimeout(30000);
InputStream is = conn.getInputStream();
bmp = BitmapFactory.decodeStream(is);
return bmp;
它会返回一个准备好保存到存储中的位图。
【讨论】：
在doInBackground中，在你得到图片的url之后。 我不明白你..因为我的 asyncktask 在我的活动类中..我的按钮在我的适配器类中..两者都是不同的文件..String url = c.getString(BUSINESS_CARD) // 这里你会得到图片的url。现在将它传递给 getBitmapFromUrl(String url)。
好的。在适配器的按钮单击方法（onclick）中，检索图像的url。
在 onclick 中使用代码：String url = listData.get(position).get(b_card);。以上是关于下载图像并保存在图库中？的主要内容，如果未能解决你的问题，请参考以下文章
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