Develop Reference

Change TextView from another XML

I my app, I have somes XML. I want to modify a TextView, but it is not in the primary XML file for this Activity.
I tried:
TextView nav_playerid = (TextView) findViewById(R.id.nav_username);
nav_playerid.setText(id_joueur_connect);
But that won't work. How can I tell the app to get this specific XML File and modify this TextView?

An unqualified findViewById will search the present contentView of the Activity
to get this specific XML File
You need to inflate the other one.
LayoutInflater inflater = LayoutInflater.from(MainActivity.this);
final View v = inflater.inflate(R.layout.other_layout, null);
// See 'v.findViewById'
TextView nav_playerid = (TextView) v.findViewById(R.id.nav_username);
nav_playerid.setText(id_joueur_connect);
But that creates a new, blank layout, so you'd also need to add that inflated view to the content view of the activity in order to see it.

Android including an xml layout to activity

I've an activity.java file in which my setContentView(R.layout.x); Now,I've an y.xml in which I've an Linear Layout,I've to attach an onclick() method to my view.
Attaching onclick() has to be in my activity.java file, How do I include y.xml.
I tried this,
1. layout = (LinearLayout) findViewById(R.layout.y);
eView = (EditText)layout. findViewById(R.id.editview);
2. eView = (EditText)findViewById(R.id.editview);
but both gives my null pointer exception, How do I include my editText
Update
final LayoutInflater lyInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
showLinearLayout = (LinearLayout) lyInflater.inflate(R.layout.y, null);
showView = (EditView) showLinearLayout.findViewById(R.id.edittext);

You can use inflation as shown below:
final LayoutInflater lyInflater = (LayoutInflater) mContext
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
LinearLayout yLayout = (LinearLayout) lyInflater .inflate(
R.layout.y, null);
eView = (EditText)yLayout.findViewById(R.id.editview);
So you won't get exception anymore. Hope it helps.

LayoutInflater is used to instantiate layout XML file into its corresponding View objects.in other words, it takes as input a XML file and builds the View objects from it.
in your scenario, you have to use LayoutInflater. read this article.

Ram.
If you want to include y xml file into your x xml file then follw this steps.
I am assuming that you want to include Linear Layout into your Activity on click of onclick() method of the button or whatever, then add the Linear Layout into your x xml file and add the android:visibility="gone" so at begin you can not show the linearlayout.
<LinearLayout
android:id="#+id/history_value_body"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:visibility="gone" > <<<<<<<<<<< HERE
----------------------------
-----------------------------
</LinearLayout>
Now, From the java class make it visible when needed, in your case into onclick method.
Like...
linear.setVisibility(View.VISIBLE); // linear is the object of your Linearlayout
If any prob then ask me.
Good Luck.

If I understand the question correctly, your Activity uses x.xml, and you also want to include another layout that is defined in y.xml.
You can do so using the <merge> or <include> tags, as described in the documentation.
Alternately, you can use a ViewStub to conditionally inflate another layout in a given place in a layout. For example, you can include a ViewStub tag in x.xml, and inflate y.xml in the same spot in the view hierarchy. Then, you may attach any click listeners you need (by using findViewById()).

You can use addView method of ViewGroup.
addView(layout, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));

How to inflate another view from another view in Android

I know in my onCreate() I can inflate a view from XML by something like:
loadingScreen = (RelativeLayout) findViewById(R.id.loadingScreen);
But how could I do this from another view? Im trying to call up a loading screen by setting its visibility from GONE to VISIBLE but cant seem to figure out how to do this from my glSurfaceView

If you want to inflate a layout the code looks like this:
LayoutInflater inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
LinearLayout myRoot = new LinearLayout(context);
View itemView = inflater.inflate(R.layout.layout_details, myRoot);
Here you first create a new LinearLayout an then inflate the layout with id R.layout.layout_details into it. The inflate method then returns the myRoot view.
Here is a tutorial about the LayoutInflater:
Layout resources in Android

Thats actually not inflating. Inflating is the process that parses a XML layout file and creates a structure of View and ViewGroup class instances out of it (setContentView() does this for you in the background for example).
What you do is getting a reference to a view in code that you have defined in your XML layout file. To change the visibility of your GLSurfaceView you have to reference it like you did above. But remember that the View (GLSurfaceView in this case) has to be defined in your layout file.
After referencing you have to call GLSurfaceView.setVisibility() to change it's visibility.
Here's an example:
GLSurfaceView glsurface = (GLSurfaceView) findViewById(R.id.myglsurfaceid);
glsurface.setVisibility(View.VISIBLE);
Of course you can use View.INVISIBLE or View.GONE either, depending on what you want to do.
If you reference a layout (such as a RelativeLayout), you may find children of this layout with the findViewById() of your RelativeLayout instance:
RelativeLayour rl = (RelativeLayout) findViewById(R.id.mylayout);
(Button) mybutton = (Button) rl.findViewById(R.id.mybutton);
But thats usually not neccessary (at least when you just started with Android) because the activities findViewById() finds all Views that are displayed, even in sublayouts. You only have to use it if you have duplicate ids in your ui structure (tbh I never had that case yet) and want to specifiy where to look for your particular View.

You can't get a reference to a View that's doesn't exists in your current Layout, or your current View, (your current Activity content) , but you can create a new View from another XML layout, using LayoutInflater from current Activity.
you can add to you current Activity content, a new View, that's what you mentioned as " loading screen ", even by showing it as a Dialog or by creating View and then add it to root layout in your Activity
I hope I helped you

If I correctly understood what you wanna do:
Supposing you have a glSurfaceView object and you wanna grab a view that's inside that one.
You'll do just the same thing you did for you normal view. Let's say a button:
Button button = (Button) glSurfaceView.findViewById(R.id.buttonid);
If you meant something different let me know in the comments.
EDIT: And then you can just set the button's visibility:
button.setVisibility(Button.GONE)

Assign fixed layout to dynamic textview

Hello
I have a loop that creates n-1 textviews, and for each of these textviews I would like a fixed layout defined in an XML file.
The code is as follows:
for(PInfo P : P_array)
{
TextView tv = new TextView(this);
tv.setText(P.getName());
tv.setWidth(P.getLength());
tv.setHeight(70);
tv.setPadding(10, 5, 10, 5);
masterView.addView(tv);
}
I would like something like tv.setLayout(R.id.textviewlayout); ... How is that done, im sure its easy (it should be) but I cant find any info on it.

This is called inflating. Try this:
LayoutInflater li = (LayoutInflater)mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
TextView tv = li.inflate(R.layout.textview, null);
Second parameter is optional parent for inflated view:
help article

Not sure exactly what you are trying to achieve but have a look in the SDK reference for ListView and ArrayAdapter.
This will enable you to build a list of custom views from an XML file.

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.