displaying data in ListView programmatically - android

I'm developing an Android App and I need to display some data in a scrollable Listview.
I will extract some strings from objects that I right now have stored in linked lists (until i come up with a better solution).
I want to display a view that looks almost like the contacts app. A list with a small picture to the left and a larger text to the right of the picture with a smaller text the bigger one. When I click on one of the items it should open a new activity.
How do I create the view? If I adds an object in the linked list it should appear in the list.
I have checked some sample code, but they all uses Arrayadapter and I dont understand how I am supposed to do.

Check this article about Adapters: http://www.vogella.com/articles/AndroidListView/article.html
If you want to add new objects in ListVew use:
adapter.notifyDataSetChenged();

Check the libraries in this question, you have what you need there:
Lazy load of images in ListView

Related

Android - Best way to show data without large amount of layout files

Thanks for all the help recently! Another question!
In the app I'm building, I currently have a layout file with an expandable lstview where you can choose 10 options. When you choose one of those options, you pick another 4 options. From picking the week, you then have 3 more options. Each of those 3 options will currently open a new activity that has a listview with a checkbox and textview in each row, with about 10 rows each.
Instead of making 30 layout files which will probably crash the app(not sure how many it would take to crash the app), I'm thinking there has to be a better way. I have looked it up and can't really find what I'm looking for. I have read a little bit about sqlite, but wouldn't you still need separate layout files to call different parts of the tables? Is there a way to make a single layout file with a list view, and fill the listview with different data from sqlite, depending on where the click came from in the expandable list view?
For example, if they click workout 29 on expandable list view, then click Week 1, then click Day 1.. can that single layout load data from sqlite db. Then if they were to go back and say click workout 30, week 2, day 3, that same layout load different info from the db?
I'm also trying to find out how to make a double expandable list view still
Thanks again!
So this is very simple all you have to do is create a DataAdapter for the listview. You can then add list view items which bind to the onclick listener and then you can clear that list and add new elements to it. a useful link would be.
https://guides.codepath.com/android/Using-an-ArrayAdapter-with-ListView
You should be using a SQLite database for all your data (unless you plan on holding the data in memory which is not a good idea if it is a rather large amount). You should just create a simple view and keep reusing it. What you will have to do is create your own adapter (extending from BaseExpandableListAdapter for Expandable list views and BaseAdapter for normal list views) and then query the SQLite databse table for the data that you need.
If you are only displaying String items, you can directly extend ArrayAdapter and then provide the array of items that you want to display for the normal list.
As far as crashing goes, there are many apps that have well over 30 layout files. Besides even if you did start loading a lot of views, Android will automatically start destroying views as it starts running low on memory and recreate them when it is needed to do so.

Set images randomly in the grid in Android

I am using a version of the "Grid View" example from the Android Developers site: http://developer.android.com/resources/tutorials/views/hello-gridview.html And I would like to display images in reach grid randomly and the image position will change in each click. Can someone please give an example of how this might be accomplished (i.e. what needs to be edited)? Thanks!
You need to implement a custom ListAdapter, where you need to check which items are visible and select then a random image which is not visible. Bute note that a total random list will confuse your users. Better sort your images by random and visualizate them same in one instance.

display a list of images in the options of an android application

I'm working on an application where I want to give the user the option of being able to select an image from a list in the options menu. Kind of like how you can select the ringtone of your phone, but with images instead.
I can display the list of images in a spinner in my main activity, but I have no idea how to translate that onto the preferences screen. Is it possible to have a spinner on the preferences screen?
You're going to need to make a custom adapter that you hand to the Spinner. Rather than giving it an adapter filled with Strings (which is what you're doing now) you're going to give it an adapter filled with ImageViews.
Here's a good example...
Simple Adapter problem, Text + Image in spinner. Java, Android

Android Displaying data on gridview

I have some data in my data base and i want to display it in android phone.I want to display my data on Grid-view because there is continuous variation in my data therefore i want to display in android like asp.net gridivew.Please anyone help me to do this or any example code to do this
You need to have two things for the Gridview:
Use Gridview component in a layout.
Inflate the elements in a getView method and set elements position by position to the Gridview items.
You can follow this link to understand it:
http://android-coding.blogspot.in/2011/09/simple-gridview-example.html
You are on the right track as you have decided yo use a dynamic view for your varying data. You can use any one of the dynamic view(list view, grid view, gallery, etc) depending on the kind of data you need to display.
If you are not familiar with these dynamic views then you should first go through some tutorials on implementation of these views. First try with a basic program for understanding the concepts. Once you are clear with the concepts then all you need to do is to replace the underneath data with the data fetched from the data base.
There are lots of tutorial available on net. Here are some links:
GridView tutorial
ListView tutorial
Feel free to discuss in case there is any doubt.

Listview with multiple images and text on single line in android?

hi i am going to make a to-do list so what i need is that to assign my task and view it as a list view in those list view need 3 text view and 3 images in this 3 images represent 3 activity like alarm, calendar and so on when i click these images its open seperatly i had i know to retrieve the data's from database to list view but did not know how to set multiple image in a single list.and make those images click able.now how can i do that i tried the lazy adaptor but it is used in the parsing phases there is no parsing in my application please help me
there are many different post all over the place about creating custom ListView items. this one is very helpfull and similar to what you want to do.
when working with images and ListViews, it's very important to implement Lazy image loading. the best implementation I know, is ferdovlasove's LazyAdapter.
enjoy...

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