How to implement a custom AlertDialog View

Question

In the Android docs on AlertDialog, it gives the following instruction and example for setting a custom view in an AlertDialog:

If you want to display a more complex view, look up the FrameLayout called "body" and add your view to it:

FrameLayout fl = (FrameLayout) findViewById(R.id.body);
fl.add(myView, new LayoutParams(FILL_PARENT, WRAP_CONTENT));

First off, it's pretty obvious that add() is a typo and is meant to be addView().

I'm confused by the first line using R.id.body. It seems that it's the body element of the AlertDialog ... but I can't just enter that in my code b/c it gives a compile error. Where does R.id.body get defined or assigned or whatever?

Here's my code. I tried to use setView(findViewById(R.layout.whatever) on the builder but it didn't work. I'm assuming because I didn't manually inflate it?

AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Title")
    .setCancelable(false)
    .setPositiveButton("Go", new DialogInterface.OnClickListener() {

    @Override
    public void onClick(DialogInterface dialog, int id) {
        EditText textBox = (EditText) findViewById(R.id.textbox);
        doStuff();
    }
});

FrameLayout f1 = (FrameLayout)findViewById(R.id.body /*CURRENTLY an ERROR*/);
f1.addView(findViewById(R.layout.dialog_view));

AlertDialog alert = builder.create();
alert.show();

Answer 1

All constants in the R class are generated from your xml files. Youshould probably just define an xml-layout with id=body to get the example through.

Answer 2

You are correct, it's because you didn't manually inflate it. It appears that you're trying to "extract" the "body" id from your Activity's layout, and that won't work.

You probably want something like this:

LayoutInflater inflater = getLayoutInflater();
FrameLayout f1 = (FrameLayout)alert.findViewById(android.R.id.body);
f1.addView(inflater.inflate(R.layout.dialog_view, f1, false));