0
在我的應用程序中，當某個活動被調用時，我正在顯示來自url的圖像。從URL中的圖像會被慢慢地加載，我想顯示一個進度對話框這裏，android-進度對話框不會很快出現
下面是我的代碼，以顯示進度對話框beofr形象出現
class ShowImageTagList extends AsyncTask<Void, Void, Void>
{
ProgressDialog dialog = new ProgressDialog(UploadPhoto.this);
protected void onPreExecute()
{
Log.e("preexcute ","called");
this.dialog.setMessage(" Loading ...");
this.dialog.setCancelable(false);
this.dialog.show();
}
protected Void doInBackground(Void... args)
{
try
{
JSONObject json = new JSONObject(Appconstants.photo_details);
JSONArray photoperson = json.getJSONArray("photopersons");
Log.e("photoperson ","value @ photoperson "+photoperson);
for(int j=0; j < photoperson.length(); j++)
{
id.add(photoperson.getJSONObject(j).getString("pid").toString());
names.add(photoperson.getJSONObject(j).getString("name").toString());
}
}
catch(Exception e)
{
Log.e("Eception caught", ""+e);
}
return null ;
}
protected void onPostExecute(Void unused)
{
Log.e("post execute ","called");
Bitmap bm = getBitmapFromURL(Appconstants.image_url.get(Appconstants.img_i));
img_to_upload.setImageBitmap(bm);
list_tag.setAdapter(new ListviewAdapter(UploadPhoto.this, names, id));
dialog.dismiss();
}
}
public static Bitmap getBitmapFromURL(String src)
{
try
{
URL url = new 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();
Log.e("Exception",e.getMessage());
return null;
}
}
進度對話框不會立即出現，它會在圖像出現之前以微秒出現，但預先執行的日誌和後臺執行的日誌會立即打印出來。當ASYN任務被調用，
如何使從開始運行進度.....