Develop Reference

Android: Load layout from xml to new layout

I want to load layout dafined in xml to newly created LinearLayout object. Is that possible?
LinearLayout new_layout = new LinearLayout(context);
new_layout.load(R.layout.my_layout); // is something like this possible?

What you're trying to achieve is usually done this way
LayoutInflater inflater = LayoutInflater.from(context);
LinearLayout newLayout = (LinearLayout) inflater.inflate(R.layout.my_layout, null);

Getting View from RelativeLayout

Programatically I have a RelativeLayout and TextView (called title) within it defined as follows:
RelativeLayout layout = new RelativeLayout(this);
final RelativeLayout.LayoutParams parameters_title =
new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT,
RelativeLayout.LayoutParams.WRAP_CONTENT);
title.setLayoutParams(parameters_title);
layout.addView(title,parameters_title);
I intend to add more textviews and buttons later. But for now, I want to "convert" (I am not sure how to put it into words) the RelativeLayout into a View in order to put it into WindowManager. I was trying to use LayoutInflater like this but it wouldn't work
LayoutInflater layoutInflater =
(LayoutInflater)this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
myView = layoutInflater.inflate(layout, null );
then the goal is to put myView into WindowManger through addView. How can I get a View from my RelativeLayout?

you can do this by getChildAt but you will have to keep the position of the view you want to get from layout. To avoid this you can set an id for your view and get the view with findViewById(). If you inflate a view from xml you will get the same views as xml. if you add some new views to the relativeLayout it will not effect the view you inflate from the xml.
when you are adding the view:
myView.setId(id);
layout.addView(myView);
when you are retrieving
View myView = layout.findViewById(id);

Cast XML layout as view in android before setContentView

I want to cast multiple XML layouts as views. Because of a change request I need to use a ViewSwitcher. So I have to cast the XML layout to Views before setContentView.
I always get a NullPointerException. I tried:
view = (View) findViewById(R.id.viewgroup_id);
view = (RelativeLayout) findViewById(R.id.viewgroup_id);
view = (View) findViewById(R.layout.xml_layout);
view = (View) getResources().getLayout(R.layout.xml_layout);

Try using LayoutInflater. Use this code inside your activity code-
LayoutInflater inflater = getLayoutInflater();
View view = inflater.inflate(R.layout.your_layout, null);

You need to inflate layouts for that
Check this link

Adding layout dynamically to ScrollView android

I want to add xml layout dynamically to scrollview in my application, but it is showing an error.
This is my code:
LinearLayout ll = (LinearLayout)findViewById(R.id.myContent1);
LayoutInflater vi = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View vv = vi.inflate(R.layout.headerone, null);
ll.addView(vv);//, new LinearLayout.LayoutParams(ll.getLayoutParams().width, ll.getLayoutParams().height));
View vv2 = vi.inflate(R.layout.headertwo, null);
ll.addView(vv2);//, new LinearLayout.LayoutParams(ll.getLayoutParams().width, ll.getLayoutParams().height));
View vv3 = vi.inflate(R.layout.headerone, null);
ll.addView(vv3);
"headerone.xml" and "headertwo.xml" are my two xml layout files.

Probably
A ScrollView is a FrameLayout, meaning you should place one child in it containing the entire contents to scroll; this child may itself be a layout manager with a complex hierarchy of objects.
But we would need to see the XML to be sure.

How to inflate one view with a layout

I have a layout defined in XML. It contains also:
<RelativeLayout
android:id="#+id/item"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
I would like to inflate this RelativeView with other XML layout file. I may use different layouts depending on a situation. How should I do it? I was trying different variations of
RelativeLayout item = (RelativeLayout) findViewById(R.id.item);
item.inflate(...)
But none of them worked fine.

I'm not sure I have followed your question- are you trying to attach a child view to the RelativeLayout? If so you want to do something along the lines of:
RelativeLayout item = (RelativeLayout)findViewById(R.id.item);
View child = getLayoutInflater().inflate(R.layout.child, null);
item.addView(child);

You inflate an XML resource. See the LayoutInflater doc .
If your layout is in a mylayout.xml, you would do something like:
View view;
LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.mylayout, null);
RelativeLayout item = (RelativeLayout) view.findViewById(R.id.item);

Though late answer,
but would like to add that one way to get this
LayoutInflater layoutInflater = (LayoutInflater)this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view = layoutInflater.inflate(R.layout.mylayout, item );
where item is the parent layout where you want to add a child layout.

It's helpful to add to this, even though it's an old post, that if the child view that is being inflated from xml is to be added to a viewgroup layout, you need to call inflate with a clue of what type of viewgroup it is going to be added to. Like:
View child = getLayoutInflater().inflate(R.layout.child, item, false);
The inflate method is quite overloaded and describes this part of the usage in the docs. I had a problem where a single view inflated from xml wasn't aligning in the parent properly until I made this type of change.

Even simpler way is to use
View child = View.inflate(context, R.layout.child, null)
item.addChild(child) //attach to your item

Try this code :
If you just want to inflate your layout :
View view = LayoutInflater.from(context).inflate(R.layout.your_xml_layout,null); // Code for inflating xml layout
RelativeLayout item = view.findViewById(R.id.item);
If you want to inflate your layout in container(parent layout) :
LinearLayout parent = findViewById(R.id.container); //parent layout.
View view = LayoutInflater.from(context).inflate(R.layout.your_xml_layout,parent,false);
RelativeLayout item = view.findViewById(R.id.item); //initialize layout & By this you can also perform any event.
parent.addView(view); //adding your inflated layout in parent layout.

layout inflation
View view = null;
LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.mylayout, null);
main.addView(view);

If you're not in an activity you can use the static from() method from the LayoutInflater class to get a LayoutInflater, or request the service from the context method getSystemService() too :
LayoutInflater i;
Context x; //Assuming here that x is a valid context, not null
i = (LayoutInflater) x.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
//OR
i = LayoutInflater.from(x);
(I know it's almost 4 years ago but still worth mentioning)

AttachToRoot Set to True
Just think we specified a button in an XML layout file with its layout width and layout height set to match_parent.
<Button xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/custom_button">
</Button>
On This Buttons Click Event We Can Set Following Code to Inflate Layout on This Activity.
LayoutInflater inflater = LayoutInflater.from(getContext());
inflater.inflate(R.layout.yourlayoutname, this);
Hope this solution works for you.!

If you want to add a single view multiple time then you have to use
layoutInflaterForButton = getActivity().getLayoutInflater();
for (int noOfButton = 0; noOfButton < 5; noOfButton++) {
FrameLayout btnView = (FrameLayout) layoutInflaterForButton.inflate(R.layout.poll_button, null);
btnContainer.addView(btnView);
}
If you do like
layoutInflaterForButton = getActivity().getLayoutInflater();
FrameLayout btnView = (FrameLayout) layoutInflaterForButton.inflate(R.layout.poll_button, null);
and
for (int noOfButton = 0; noOfButton < 5; noOfButton++) {
btnContainer.addView(btnView);
}
then it will throw exception of all ready added view.

If you are you trying to attach a child view to the RelativeLayout? you can do by following
RelativeLayout item = (RelativeLayout)findViewById(R.id.item);
View child = getLayoutInflater().inflate(R.layout.child, item, true);

I had the hardest time with this error, because of my unique circumstances, but finally found a solution.
My situation: I am using a separate view (XML) which holds a WebView, then opens in an AlertDialog when I click a button in my main activity view. But somehow or another the WebView belonged to the main activity view (probably because I pull the resource from here), so right before I assigned it to my AlertDialog (as a view), I had to get the parent of my WebView, put it into a ViewGroup, then remove all the views on that ViewGroup. This worked, and my error went away.
// set up Alert Dialog box
AlertDialog.Builder alert = new AlertDialog.Builder(this);
// inflate other xml where WebView is
LayoutInflater layoutInflater = (LayoutInflater)this.getSystemService
(Context.LAYOUT_INFLATER_SERVICE);
View v = layoutInflater.inflate(R.layout.your_webview_layout, null);
final WebView webView = (WebView) v.findViewById(R.id.your_webview_id);
// more code...
.... later on after I loaded my WebView ....
// first, remove the parent of WebView from it's old parent so can be assigned a new one.
ViewGroup vg = (ViewGroup) webView.getParent();
vg.removeAllViews();
// put WebView in Dialog box
alert.setView(webView);
alert.show();

With Kotlin, you can use:
val content = LayoutInflater.from(context).inflate(R.layout.[custom_layout_name], null)
[your_main_layout].apply {
//..
addView(content)
}

When add a layout to an Activity in Kotlin, see these steps:
Add just in Activity - One layout as a parent
Xml file of new
Layout Give the value of R.
val parent: LinearLayout =findViewById(R.id.stars)
val view =
LayoutInflater.from(applicationContext).inflate(R.layout.another, parent,false)
Where parent is not necessary, can be null But warning message will be appear
view.findViewById<ImageView>(R.id.ivTimer).setImageResource(R.drawable.t2)
Any view must be set value in this way, finally add
parent.apply { addView(view)}

I had used below snippet of code for this and it worked for me.
LinearLayout linearLayout = (LinearLayout)findViewById(R.id.item);
View child = getLayoutInflater().inflate(R.layout.child, null);
linearLayout.addView(child);