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Android Show Blob Images in listview when scroll.

Hi I want to show the images in listview when user scroll the list.
I retrieved the image from database(blob) not from web service.
for example
I have an 40 items in the list view and in my mobile screen 10 item is visible. when i scroll the list it load the next images. i don't want to load the 40 images concurrently.
list will show images between Fisrt Visible Position and Last Visible Position.
Like in a twitter app the images first blank when user scroll then it load in the listview
Thanks in advance.

The solution you finding is called Lazy Loading Adapter, this tutorial will work as you want check this link, this loads images in lazy manner.

Android - Displaying Image and Text dynamically in ListView

How do I implement a listview which displays images an text dynamically from the web? Each image has some descriptions to it and I need them to display correctly in each list. The images change every once in a while. So I have to retrieve up to date contents.
I have read this, but have no idea how to include text into it. Any help here?
Thanks.

Here you will find full details and along with Full working Source code
Android lazy image loader example

Use an ListView Adapter like here: http://android.amberfog.com/?p=296.
The getView Method is executed for every row of your ListView, so you have to place your code to load the images right there
When the Data changes simply call notifyDataSetChanged on the ListView Adapter and the ListView will refresh (executs getView again).

gridview load remote image . updating view?

I am using a GridView having image as child items.
The getView functions loads a default image from the application "Loading.gif" for all the child items.
In another thread I load all the images to some Bitmap type into the adapter.
Is it wise enough to call adapter.notifyDataSetChanged() after each image is loaded ?
Or is there and alternative way to directly update the image ?

Checkout the technique used in ListView , where default image used in listview items. And a thread load images for list items and update the new images without adapter.notifyDataSetChanged() called.
http://iamvijayakumar.blogspot.com/2011/06/android-lazy-image-loader-example.html
If you want more efficient way to do this then check this out.
http://developer.android.com/resources/samples/XmlAdapters/src/com/example/android/xmladapters/ImageDownloader.html

Help regarding asynchronous loading of images in Android GridView

I am new Android developer. I want to achieve the following: On a particular screen (Activity) I have a grid view with images being set onto it. I have hundreds of thumbnail images coming from a server via http request. Now I don't want the gridview (with 4 columns in one row) to load the images in one go. Instead I want images to be loaded one row at a time (4 images), with other tiles of the grid view showing progess bar. Also when only few images are displayed the user should still be able to scroll the gridview vertically and thereby displaying empty gridview frames or tiles but if the scrolling is paused the frames or tiles of gridview are again loaded one row at a time.
I am looking for ideas to achieve this.
Thanks in advance for your responses.

In your Adapter's getView method set the image with a indefinite progress spinner.
After that start an AsyncTask to download the image if its not present in the object returned by getItem. Pass the item's position to the asynctask.
In AsyncTask's onPostExecute set the image to the view at position and hide the progress spinner.
Downloading the image in AsyncTask will ensure that your gridview is filled with items(empty) and responds to scrolling.

Gallery(Horizontal ListView) inside a ListView

Ok i wasted 1 day of my life i think now is the time to ask for help :D
I have a listview that has an image text ..etc (custom view) and one of its
elements is a Gallery. (Aka horizontal listview)
Gallery also is a custom view.
SO.. here is the problem:
I call the adaptor to set the custom view in the listview.Ok for now.
Inside the listview adaptor i call the Gallery adaptor.Ok for now.
Everything render out as it should be with a very nice complex interface.
Now the problem
When i scroll the Gallery the data change to what the data should have been if i scrolled the gallery of the last listview row rendered.(Hope you get me here)
Ex.gallery in first listview has photos of the sea.
gallery in 2nd listview has photos of a building.
If i scroll the first gallery the photos change from "sea" to building".
Meaning ... each time the listview adapter's getView is called i feed the galleryadapter with data
gal1.setAdapter(new GalleryAdapter(CON,PASS[position]));
What i'm thinking as a possible solution is :
Hardcore , preload all the data in the custom Gallery of each listview.
Figure a way that when i scroll the Gallery element within a listview , the gallery adapter to be aware of the index of listbox and load the correct data.
I think the second solution is more elegant,and more difficult but considering that if i go for the 1st solution there will be >40 views loaded at all times so no biggy.
So.. I;m asking for your help.Is there a 3rd , 4rth .. way?Is anyone of my suggestions even possible?If so please point a way of implement to code.
Keed in mind that i want to be able to do multiple scrollings at any given moment.
So i think that my 2nd suggestiong might have some problems there.

Try using same gallery adapter for all list items and in getView of list adapter just change the data for gallery adapter.
After setting the data in getView just notify gallery adapter.
out side getView(maybe in constructor of list adapter)
GalleryAdapter galleryAdapter=new GalleryAdapter();
in getView
galleryAdapter.setData(CON,PASS[position]);
gal1.setAdapter(galleryAdapter);