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Add XML content to a View

im developing an application and I need to add elements dynamically. I wonder if I can append elements (stored in a XML file) in my current Activity, like innerHTML in JavaScript.
I tried LayoutInflater but that replaces all the content and I need to append.
Thanks!

The easiest way to do this is to use the LayoutInflater as you said. I'm not sure how you were doing it (hence why I asked to see your inflating code), but the simplest way to understand is to do the following:
LayoutInflater inflater = getLayoutInflater();
View viewToAppend = inflater.inflate(R.layout.some_layout, null);
// Optional, create LayoutParams and apply to view with
// viewToAppend.setLayoutParams(params);
mainView.addView(viewToAppend);

Why to use Inflater in listview

I always had ambiguity on why we need to use inflater in android, Why are they used in ListView for custom layouts (like below)?
What is an Inflater ?
What is the advantage of using Inflater ?
public class MobileArrayAdapter extends ArrayAdapter<String> {
private final Context context;
private final String[] values;
public MobileArrayAdapter(Context context, String[] values) {
super(context, R.layout.list_mobile, values);
this.context = context;
this.values = values;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View rowView = inflater.inflate(R.layout.list_mobile, parent, false);
TextView textView = (TextView) rowView.findViewById(R.id.label);
ImageView imageView = (ImageView) rowView.findViewById(R.id.logo);
textView.setText(values[position]);
Thanks,

What is an Inflater ?
To summarize what the LayoutInflater Documentation says... A LayoutInflater is one of the Android System Services that is responsible for taking your XML files that define a layout, and converting them into View objects. The OS then uses these view objects to draw the screen.
I always had ambiguity on why we need to use inflater in android, Why
are they used in android ListView for a custom layout ?
Typically, you don't ever need to directly use a LayoutInflater. Android does most of the layout inflation for you when you call setContentView() in the onCreate() method of your activity. So you, as the programmer, are responsible for making sure the views are inflated. Now you want to inflate views in the context of a ListView. The Adapter class can do the inflation for you if you do not want to customize each item. But if you want to customize the views shown in a list, you will have to manually inflate each view with the LayoutInflater, since there is no other existing method you can use.
What is the advantage of using Inflater ?
There is no advantage to using it. You are required to use a LayoutInflater in some shape or form to inflate your static XML layouts.
Alternatively, you could create views dynamically with java code. However, you would need to call methods to set each property for the view by hand. In my opinion, it is easier to use the XML/inflation process. In addition, Android pre-processes your XML files at build time, so this results in a faster execution time.

I always had ambiguity on why wee need to use inflater in android, Why are they used in android ListView for a custom layout ?
They are used to create the Views for each row.
What is an Inflater ?
A system service that creates a View out of an XML layout.
In the below code i am trying to understand why Inflator is used ?
The inflater is used to create the Views for the rows.
What is the advantage of using Inflater ?
Compared to what? How do you want to create the Views out of the XML layout?

Put simply, an inflater allows you to create a View from a resource layout file so that you do not need to create everything programmatically.
In your example, you inflate the layout R.layout.list_mobile. This lets you access all of the views within it. For example, you then call:
TextView textView = (TextView) rowView.findViewById(R.id.label);
By calling rowView.findViewById() you are able to access views that were created within that layout. Often for ListViews you will have a row XML file that you then inflate and put your data into the views.

How to add child layouts in a Custom built layout in android

I have created some xml layouts. Now I am creating a custom layout (in my java file) with some elements and want to add the previously created layout(xml layouts). How can I do that?

You can use LayoutInflater to inlate layouts. And add inflated view to your custom view by addView() method
For ex:
LayoutInflater mInflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
ViewGroup viewTobeLoaded = mInflater.inflate(R.layout.ilan_list_item, null);
yourView.addView(viewTobeLoaded);
Hope helps

Use <include> tag in your new layout. See docs here.

What does it mean to inflate a view from an xml file?

I am new to android development and keep coming across references to Inflating views from a layout xml file. I googled and searched the development guide but still wasn't able to pick up a sense for what it means. If someone could provide a very simple example, it'd be much appreciated.

When you write an XML layout, it will be inflated by the Android OS which basically means that it will be rendered by creating view object in memory. Let's call that implicit inflation (the OS will inflate the view for you). For instance:
class Name extends Activity{
public void onCreate(){
// the OS will inflate the your_layout.xml
// file and use it for this activity
setContentView(R.layout.your_layout);
}
}
You can also inflate views explicitly by using the LayoutInflater. In that case you have to:
Get an instance of the LayoutInflater
Specify the XML to inflate
Use the returned View
Set the content view with returned view (above)
For instance:
LayoutInflater inflater = LayoutInflater.from(YourActivity.this); // 1
View theInflatedView = inflater.inflate(R.layout.your_layout, null); // 2 and 3
setContentView(theInflatedView) // 4

"Inflating" a view means taking the layout XML and parsing it to create the view and viewgroup objects from the elements and their attributes specified within, and then adding the hierarchy of those views and viewgroups to the parent ViewGroup. When you call setContentView(), it attaches the views it creates from reading the XML to the activity. You can also use LayoutInflater to add views to another ViewGroup, which can be a useful tool in a lot of circumstances.

Inflating is the process of adding a view (.xml) to activity on runtime. When we create a listView we inflate each of its items dynamically. If we want to create a ViewGroup with multiple views like buttons and textview, we can create it like so:
Button but = new Button();
but.setText ="button text";
but.background ...
but.leftDrawable.. and so on...
TextView txt = new TextView();
txt.setText ="button text";
txt.background ... and so on...
Then we have to create a layout where we can add above views:
RelativeLayout rel = new RelativeLayout();
rel.addView(but);
And now if we want to add a button in the right-corner and a textview on the bottom, we have to do a lot of work. First by instantiating the view properties and then applying multiple constraints. This is time consuming.
Android makes it easy for us to create a simple .xml and design its style and attributes in xml and then simply inflate it wherever we need it without the pain of setting constraints programatically.
LayoutInflater inflater =
(LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View menuLayout = inflater.inflate(R.layout.your_menu_layout, mainLayout, true);
//now add menuLayout to wherever you want to add like
(RelativeLayout)findViewById(R.id.relative).addView(menuLayout);

A layman definition for inflation might be to convert the XML code to Java code. Just a way to understand, e.g., if we have a tag in XML, OS has to create a corresponding Java object in memory, so inflatter reads the XMLtags, and creates the corresponding objects in Java.

I think here "inflating a view" means fetching the layout.xml file drawing a view specified in that xml file and POPULATING ( = inflating ) the parent viewGroup with the created View.

Because we make UI into XML but view objects is what we display so we somehow need to convert xml into view objects so inflating means we are converting xml into view objects so that it can be displayed, for this we need a service called layout inflator service and give it an xml and it will be convert for you.

In the iOS UIKit universe, this means getting the reference to the .Xib (which is XML, just like android) file and adding it to the current ViewController's view hierarchy.

Inflator in Android Application Development

Can anybody please tell What Inflator is and how it is being used in an Android application?
I don't know the exact use of it and Why it is being used.

My preferred way to handle inflation:
//First get our inflater ready, you'll need the application/activity context for this
LayoutInflater mInflater;
mInflater = LayoutInflater.from(mContext);
//Inflate the view from xml
View newView = mInflater.inflate(R.layout.my_new_layout, null);
//Then you'll want to add it to an existing layout object
mMainLayout.add(newView);
//Or perhaps just set it as the main view (though this method can also
// inflate the XML for you if you give it the resource id directly)
setContentView(newView);
Basically, you use it to inflate existing xml layouts at runtime. Usually you go ahead and insert those new views into previously defined ViewGroups or List objects.

Not quite sure what you mean, but if its related with inflating views, its used to load layout xml files into your application. e.g by
View myWelcome = View.inflate(this, R.layout.welcome, null);
Its easier and consider best practice to have you view definition inside layout xml files, instead of creating your views fully by code.

layout inflator is used to return a java object of your complete layout
suppose you have a layout xml file in which the root element is relative layout and it contains a imageview and textview then using layout inflator you can return a view object that refers to entire layout.
this basically is used in list view and grid view to plug into them a layout object of single row or element which is to be repeated.

you were asking for use of Inflator..
basically when you want to use two xml files in one java class ,inflator is used and its code is simple which is given below..
TextView text;
View layout;
LayoutInflater inflator=getLayoutInflater();
layout =inflator.inflate(R.layout.new_xml_that you want to use in that java class,null);
text=(TextView)layout.findViewById(R.id.text);
text.setText("progressing");
here i use textview,this is present in next xml with id=text
thats it..
if you find this worthy then please like this..
thanks