AlertDialog.Builder with custom layout and EditText; cannot access view

I am trying to create an alert dialog with an EditText object. I need to set the initial text of the EditText programmatically. Here's what I have.

AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);
// ...Irrelevant code for customizing the buttons and title
AlertDialog alertDialog = dialogBuilder.create();
LayoutInflater inflater = this.getLayoutInflater();
alertDialog.setContentView(inflater.inflate(R.layout.alert_label_editor, null));
EditText editText = (EditText) findViewById(R.id.label_field);
editText.setText("test label");
alertDialog.show();

What do I need to change so that I can have a valid EditText object?

[edit]

So, it was pointed out by user370305 and others that I should be using alertDialog.findViewById(R.id.label_field);

Unfortunately there is another issue here. Apparently, setting the content view on the AlertDialog causes the program to crash at runtime. You have to set it on the builder.

AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);
// ...Irrelevant code for customizing the buttons and title
dialogBuilder.setView(inflater.inflate(R.layout.alert_label_editor, null));
AlertDialog alertDialog = dialogBuilder.create();
LayoutInflater inflater = this.getLayoutInflater();
EditText editText = (EditText) alertDialog.findViewById(R.id.label_field);
editText.setText("test label");
alertDialog.show();

Unfortunately, when you do this, alertDialog.findViewById(R.id.label_field); now returns null.

[/edit]

Solution 1:

editText is a part of alertDialog layout so Just access editText with reference of alertDialog

EditText editText = (EditText) alertDialog.findViewById(R.id.label_field);

Update:

Because in code line dialogBuilder.setView(inflater.inflate(R.layout.alert_label_editor, null));

inflater is Null.

update your code like below, and try to understand the each code line

AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);
// ...Irrelevant code for customizing the buttons and title
LayoutInflater inflater = this.getLayoutInflater();
View dialogView = inflater.inflate(R.layout.alert_label_editor, null);
dialogBuilder.setView(dialogView);

EditText editText = (EditText) dialogView.findViewById(R.id.label_field);
editText.setText("test label");
AlertDialog alertDialog = dialogBuilder.create();
alertDialog.show();

Update 2:

As you are using View object created by Inflater to update UI components else you can directly use setView(int layourResId) method of AlertDialog.Builder class, which is available from API 21 and onwards.

Solution 2:

Use this one

   AlertDialog.Builder builder = new AlertDialog.Builder(activity);
    // Get the layout inflater
    LayoutInflater inflater = (activity).getLayoutInflater();
    // Inflate and set the layout for the dialog
    // Pass null as the parent view because its going in the
    // dialog layout
    builder.setTitle(title);
    builder.setCancelable(false);
    builder.setIcon(R.drawable.galleryalart);
    builder.setView(inflater.inflate(R.layout.dialogue, null))
    // Add action buttons
            .setPositiveButton("OK", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int id) {

                    }
                }
            });
    builder.create();
    builder.show();