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Dynamically adding subitems to ListView in Android

I am trying to dynamically add information to a ListView. The information I am adding consists of a "Device Name" (the main item) and "MAC Address" (the sub item). An example from online is below. Note: I want to replace Item 1 with a device 1's name, sub item 1 with device 1's MAC address, and so on. This MUST be done dynamically because the list is being populated as devices are scanned for.
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Before this is marked as a repeat, I have looked at the following questions and they have not helped me: Adding ListView Sub Item Text in Android, How to add subitems in a ListView, Adding Items and Subitems to a ListView
The conclusion I have come to through reading these questions is that I need to implement a custom ArrayAdapter and override the getView() method. I have created a custom layout with two text views in it:
cyan_list.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/main_item"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#color/cyan"/>
<TextView
android:id="#+id/sub_item"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#color/dark_cyan"/>
</LinearLayout>
I then try to create a custom ArrayAdapter in my Activity class, but I am lost as to what to put in my public View getView(final int position, View convertView, ViewGroup parent) method. Additionally, is creating a custom ArrayAdapter necessary if all I am trying to do is add a textview sub item?

The answer to your question is: NO, you don't need to create a custom ArrayAdapter if you just want to add items. I recommend, however, creating it if your layout is customized, as you'll gain so much control over the items you're displaying. You didn't add your code where you create your ArrayAdapter, but in your case I'd use this constructor. The important part is the third parameter: In your activity, you should store an ArrayList with the initial items you're adding to your ArrayAdapter, then, if you want to add a new item, you simply add it to the ArrayAdapter and call notifyDataSetChanged() on your adapter. Simply doing that, your item will be added to the layout and displayed. If you need to override the GetView method for your own ArrayAdapter, I recommend this link, it helped me understanding the whole thing.

are you searching some listview example in google like those tutorials :
http://www.vogella.com/tutorials/AndroidListView/article.html
http://www.mkyong.com/android/android-listview-example/
I think they explain step by step how to create a list adapter

You need to add getter method into your Adapter
YourAdapter ...{
List<Device> items = new ArrayList<Device>;
public List<Device> getItems(){
return items;
}
}
then change item that you need
...{
//for 1s item
Device item = getItems().get(0);
item.setTitle(macAdress)
}
and call notifyDataSetChanged for your adapter
...
yourListView.getAdapter().notifyDataSetChanged();
}
Thats it. Now you are able to change your list data.
And for your question, i think yes. Is better to create your own adapter in order to have simple possibility to exentd it later. And in your case (if you dont want to change your adapter after each title change) you deffinetly need custom one. Cheers

can't set view background

I want to make an application that show lyric of sound with music,
I put lyrics in a custom made listview with layout below ( layout for row's ), and time of that lyric in text separated with comma,
then, I want to scroll with media.
This is my custom layout for rows:
<TextView
android:id="#+id/custom_text_arabic"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="10dp"
android:gravity="center"
android:lineSpacingExtra="15dp"
android:textSize="20sp" />
<TextView
android:id="#+id/custom_text_persian"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:lineSpacingExtra="10dp"
android:textColor="#999999"
android:textSize="12sp" />
</LinearLayout>
and I have an adapter for this custom row layout in list view,
I have a music file that plays with MediaPlayer and I get current position of sound and check that in an array of time to find the position of row in list view, then I scroll to that row in a listview, along side this things, I want that row background change to black!
So, I get that row with this code and change it!
// cAdapter is the name of my BaseAdapter and whereIsMe is current child of listview
// that i want to manipulate it
View mVi = cAdapter.getView(whereIsMe-1, null, lv);
TextView persian = (TextView) mVi.findViewById(R.id.custom_text_persian);
// this toast works great!
Toast.makeText(getApplicationContext(),persian.getText(), Toast.LENGTH_LONG).show();
// this part of code is not working!
persian.setBackgroundColor( Color.BLACK );
the problem is:
I can Toast Text in a TextView perfectly! But I can't change that TextView Background or any other manipulation! why and how can I fix that?

Calling getView doesn't return the actual child of the ListView. There are two options, you can call getChild for the ListViewand update the background color or call notifyDataSetChanged and set the background color in your adapter getView method.

The getView method of the adapter is not meant to be used as you are using it.
Read some tutorials on creating a custom adapter for a listView. Then you can do whatever you want.
Here is a good read on custom adapters;
http://www.vogella.com/tutorials/AndroidListView/article.html
For getting the view you want from outside the adapter use something like this:
View view;
int nFirstPos = lv_data.getFirstVisiblePosition();
int nWantedPos = invalidaEste - nFirstPos;
if ((nWantedPos >= 0) && (nWantedPos <= lv_data.getChildCount())
{
view = lv_data.getChildAt(nWantedPos);
if (view == null)
return;
// else we have the view we want
}
Sometimes listView.getChildAt(int index) returns NULL (Android)
This happens because getView is called internally to create a view. by what you are doing you are actually creating a new view which is not added to any screen/layout so any changes you do wont be reflected on the UI

How to manage list views Checkboxes Automatically checking?

This is my list i want My problem is when i scroll list view then the check boxes(which are the items of this List ) are automatically checked
ex - if i checked first then 4 automatically being checked.
My first goal:
1. want to stretch my list to full i will wrap it into Scrollview how
2. i can prevent it to automatically checked
.
<ListView
android:id="#+id/ListViewProducts"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_column="0"
android:layout_span="2"
android:clickable="true"
android:isScrollContainer="true"
android:saveEnabled="true"
android:scrollbarAlwaysDrawVerticalTrack="true"
android:scrollbarSize="10sp"
android:scrollbars="vertical" >
</ListView>

Create your own BaseAdapter.
Keep in mind, that ALL views in your listview you see are temporary. They will be recycled when you'll scroll away. The reason is - you can have >9000 elements in your list. So, the way you create views must depend on some kind of (!) data.
Here is nince tutorial on how to create your own list.
Make X-th checkbox depend on X-th boolean in the list. A bit confusing first time I know, but this is the best way.
class MyAdapter extends BaseAdapter{
List<boolean> myCheckBoxes;
boolean getItem(int arg0){
return myCheckBoxes.get(arg0);
}
View getView(int arg0, View arg1, ViewGroup arg2){
...
...//See article
myView.setChecked(getItem(arg0));
...
return myView;
}
And in your activity
ListView myListView;
...
myListView.setAdapter(new MyAdapger(...));

You can't put a listview into a scrollview, two views scrolling in the same direction will not work nicely. Just put the listview in your non scrolling layout (frame- , list-, relativelayout).
Use an Adapter that sets every listview's row's views according to the data to be displayed.

ListView already extends ScrollView and doesn't need to have another one to surround it.
try looking at this post on creating custom listView items. you can implement a checkBox in them and make is have android:checked="false"

ListVew already extends ScrollView no need to implement it on ListView
for AutoCheck follow this link:
Check box checked Automatically in listview when scrolling the list.

There's no need to implement scrollview in listview becoz it is already extends to scrollview.
I think your listview is not able to handle the recycling of items properly.So to solve this problem go through the below link.
Getting an issue while checking the dynamically generated checkbox through list view

Creating table rows programmatically while defining layout in XML

I am trying to add rows to a TableLayout that I define in an XML file. The XML file contains a header row for the table.
I can add new rows quite well using info from various tutorials but the code required for setting up the layout for the new rows is a horrendous mess and it seems like a pain in the ass to maintain whenever the layout for the header row changes.
Is it possible to create new rows to a TableLayout while still defining the row layout in XML? For example define a template row in XML, obtain a handle to it in code and then clone the template whenever I need it.
Or is the right way to do this somehow completely different?

Your proposed approach will work fine and it more or less matches the common pattern used when populating ListView items.
Define a layout that contains a single row. Obtain a LayoutInflater by using LayoutInflater.from(myActivity). Use this inflater to create new rows using your layout like a template. Generally you will want to use the 3-argument form of LayoutInflater#inflate passing false for the third attachToRoot parameter.
Let's say you wanted to use a template layout with a label and a button in each item. It might look something like this: (Though yours would define your table rows instead.)
res/layout/item.xml:
<LinearLayout android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView android:id="#+id/my_label"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<Button android:id="#+id/my_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
Then at the point where you inflate:
// Inflate the layout and find the component views to configure
final View item = inflater.inflate(R.layout.item, parentView, false);
final TextView label = (TextView) item.findViewById(R.id.my_label);
final Button button = (Button) item.findViewById(R.id.my_button);
// Configure component views
label.setText(labelText);
button.setText(buttonText);
button.setOnClickListener(buttonClickListener);
// Add to parent
parentView.addView(item);

How to load linearlayout dynamically after checking a condition in the class file?

Hey guys please help me out I am new to android application development
Here is the scenerio: This is my layout declaring xml file:
<LinearLayout xxx
<Textview aaa>
</TextView>
</LinearLayout>
//The below LinearLayout I need to display when it meets some condition in java class
i.e if(true) then display the following layout else dont. I can check this condition only after user provides some input.
<LinearLayout xxx
<Textview aaa>
To be displayed after the condition is checked
</TextView>
</LinearLayout>
//following layout is displayed with the first one.
<LinearLayout xxx
<Textview aaa>
</TextView>
</LinearLayout>
Any idea how to do it?

Take a few moments to read the android dev guide. It is worth the time: http://developer.android.com/guide/topics/ui/index.html
Basically, you want to use IDs to refer to the xml layout:
android:id="#+id/myxmlid"
and in your java file:
LinearLayout ll = findViewById(R.id.myxmlid);
if (yourCondition)
mainLayout.add(ll);
I'm assuming that you want to add a widgets to the current layout, rather than just change the text of the current TextView.
Also, this assumes that you want to add more than just a new TextView. If you only need that, you don't need to wrap it in a LinearLayout, which is used to add rows or columns of widgets.

You don't replace your entire layout programmatically just to change the text in one TextView. The way this kind of thing is handled in android, is to include a field in your Activity class for your textview, then instantiate it in your onCreate() method with findViewById() after you've called setContentView() to load the layout so that you can access that TextView's fields and methods.
First, you TextView needs an id in the layout xml.
<TextView android:id="#+id/sometext"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
Then in your Activity...
TextView mTextView;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mTextView = (TextView) findViewById(R.id.sometext);
}
Somewhere else in the program...
public void myMethod(){
mTextView.setText("Text says this now");
}
Hopefully that gets the idea across. Good luck!

Thank Aleadam for suggesting me to read the link. Follwoing was my approach to get the output.
What I did was I assigned my LinearLayout Visibility to "GONE" (android:Visibility="GONE") when declarning the XML, and in the program after the condition is met, changed the visibility to "VISIBLE". (by using layout.setVisibility(View.VISIBLE))