【发布时间】：2015-07-20 02:38:53
【问题描述】：
我在我的代码中的图像视图上设置了一个图像（通过互联网下载）。我通过 json 获取这张图片。
我想在 whats 应用程序上分享这张图片，但我不知道文件名或其路径。
我试过这个代码
Intent share = new Intent(Intent.ACTION_SEND);
share.setType("image/*");
share.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(new File(root.getAbsolutePath() + "/DCIM/Camera/image.jpg"));
startActivity(Intent.createChooser(share,"Share via"));
但正如你看到的，它传递了一个文件路径，我不知道文件路径也不知道文件名。
有没有可能我可以从 ImageView 中获取图像并通过share.putExtra....分享它
因为我可以通过 whats 应用轻松分享文本。
我专门从 ImageView 方法获取图像，因为它满足我的要求，而不是通过文件路径名获取图像。
我的 jsonfetcher
公共类 DownloadJSON 扩展 AsyncTask { // 私有最终 ProgressDialog progressDialog;
@Override
protected void onPreExecute() {
super.onPreExecute();
pd = new ProgressDialog(CanadaJson.this);
pd.setTitle("Getting the dishes from our Server Cookers");
pd.setMessage("The waiter is getting the menu...");
pd.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
pd.setIndeterminate(true);
pd.setCancelable(false);
pd.show();
}
@Override
protected Void doInBackground(Void... params) {
// Create an array
arraylist = new ArrayList<HashMap<String, String>>();
// Retrieve JSON Objects from the given URL
jsonobject = JSONfunctions.getJSONfromURL("https://lit-hamlet-6856.herokuapp.com/eventsList/TECHNICAL");
Log.d("Json Code",jsonobject.toString());
try {
// Locate the array name in JSON
jsonarray = jsonobject.getJSONArray("events");
for (int i = 0; i < jsonarray.length(); i++) {
HashMap<String, String> map = new HashMap<String, String>();
jsonobject = jsonarray.getJSONObject(i);
// Retrive JSON Objects
map.put("Name", jsonobject.getString("Name"));
map.put("Time", jsonobject.getString("Time"));
map.put("Serves", jsonobject.getString("Serves"));
map.put("ingredients", jsonobject.getString("ingredients"));
map.put("Description",jsonobject.getString("Description"));
// Set the JSON Objects into the array
arraylist.add(map);
}
} catch (JSONException e) {
Log.e("Error", e.getMessage());
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(Void args) {
// Locate the listview in listview_main.xml
//setContentView(R.layout.listview_main);
listview = (ListView) findViewById(R.id.listview);
// Pass the results into ListViewAdapter.java
adapter = new ListViewAdapter(CanadaJson.this, arraylist);
// Set the adapter to the ListView
listview.setAdapter(adapter);
// Close the progressdialog
pd.dismiss();
// textView.setVisibility(View.VISIBLE);
// mProgressDialog.dismiss();
super.onPostExecute(args);
}
}
那么我就是这样设置的。
imageLoader.DisplayImage(resultp.get(FirstActivity.ingredients), flag);
ImageLoader 类（我如何下载图像的方法）
public class ImageLoader {
MemoryCache memoryCache = new MemoryCache();
FileCache fileCache;
private Map<ImageView, String> imageViews = Collections.synchronizedMap(new WeakHashMap<ImageView, String>());
ExecutorService executorService;
// Handler to display images in UI thread
Handler handler = new Handler();
public ImageLoader(Context context) {
fileCache = new FileCache(context);
executorService = Executors.newFixedThreadPool(5);
}
final int stub_id = R.drawable.icon;
public void DisplayImage(String url, ImageView imageView) {
imageViews.put(imageView, url);
Bitmap bitmap = memoryCache.get(url);
if (bitmap != null)
imageView.setImageBitmap(bitmap);
else {
queuePhoto(url, imageView);
imageView.setImageResource(stub_id);
}
}
private void queuePhoto(String url, ImageView imageView) {
PhotoToLoad p = new PhotoToLoad(url, imageView);
executorService.submit(new PhotosLoader(p));
}
private Bitmap getBitmap(String url) {
File f = fileCache.getFile(url);
Bitmap b = decodeFile(f);
if (b != null)
return b;
// Download Images from the Internet
try {
Bitmap bitmap = null;
URL imageUrl = new URL(url);
HttpURLConnection conn = (HttpURLConnection) imageUrl.openConnection();
conn.setConnectTimeout(30000);
conn.setReadTimeout(30000);
conn.setInstanceFollowRedirects(true);
InputStream is = conn.getInputStream();
OutputStream os = new FileOutputStream(f);
Utils.CopyStream(is, os);
os.close();
conn.disconnect();
bitmap = decodeFile(f);
return bitmap;
} catch (Throwable ex) {
ex.printStackTrace();
if (ex instanceof OutOfMemoryError)
memoryCache.clear();
return null;
}
}
// Decodes image and scales it to reduce memory consumption
private Bitmap decodeFile(File f) {
try {
// Decode image size
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
FileInputStream stream1 = new FileInputStream(f);
BitmapFactory.decodeStream(stream1, null, o);
stream1.close();
// Find the correct scale value. It should be the power of 2.
// Recommended Size 512
final int REQUIRED_SIZE = 256;//control quality of images
int width_tmp = o.outWidth, height_tmp = o.outHeight;
int scale = 1;
while (true) {
if (width_tmp / 2 < REQUIRED_SIZE
|| height_tmp / 2 < REQUIRED_SIZE)
break;
width_tmp /= 2;
height_tmp /= 2;
scale *= 2;
}
// Decode with inSampleSize
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize = scale;
FileInputStream stream2 = new FileInputStream(f);
Bitmap bitmap = BitmapFactory.decodeStream(stream2, null, o2);
stream2.close();
return bitmap;
} catch (FileNotFoundException e) {
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
// Task for the queue
private class PhotoToLoad {
public String url;
public ImageView imageView;
public PhotoToLoad(String u, ImageView i) {
url = u;
imageView = i;
}
}
class PhotosLoader implements Runnable {
PhotoToLoad photoToLoad;
PhotosLoader(PhotoToLoad photoToLoad) {
this.photoToLoad = photoToLoad;
}
@Override
public void run() {
try {
if (imageViewReused(photoToLoad))
return;
Bitmap bmp = getBitmap(photoToLoad.url);
memoryCache.put(photoToLoad.url, bmp);
if (imageViewReused(photoToLoad))
return;
BitmapDisplayer bd = new BitmapDisplayer(bmp, photoToLoad);
handler.post(bd);
} catch (Throwable th) {
th.printStackTrace();
}
}
}
boolean imageViewReused(PhotoToLoad photoToLoad) {
String tag = imageViews.get(photoToLoad.imageView);
if (tag == null || !tag.equals(photoToLoad.url))
return true;
return false;
}
// Used to display bitmap in the UI thread
class BitmapDisplayer implements Runnable {
Bitmap bitmap;
PhotoToLoad photoToLoad;
public BitmapDisplayer(Bitmap b, PhotoToLoad p) {
bitmap = b;
photoToLoad = p;
}
public void run() {
if (imageViewReused(photoToLoad))
return;
if (bitmap != null)
photoToLoad.imageView.setImageBitmap(bitmap);
else
photoToLoad.imageView.setImageResource(stub_id);
}
}
public void clearCache() {
memoryCache.clear();
fileCache.clear();
}
}
【问题讨论】：