Cannot resolve getButton method after creating alertDialog

Question

I've tried to solve this issue reading around on stackoverflow and also I've tried to understand better the use of getButton method reading directly from android studio website. Below the description directly from developer.android.com (bold is mine) :

public Button getButton (int whichButton)

Gets one of the buttons used in the dialog. Returns null if the specified button does not exist or the dialog has not yet been fully created (for example, via Dialog.show() or Dialog.create()).

MapsActivity.java

As you can see below I use getButton method after Dialog.show() but i get error: cannot find symbol method getButton(int) . Could you tell me which is the problem? Thanks

...

case R.id.settings:

                    AlertDialog.Builder builder2 = new AlertDialog.Builder(this, R.style.SettingDialogStyle);

                    LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                    View v = inflater.inflate(R.layout.setting_alert_dialog, null);


                    SeekBar sb = (SeekBar) v.findViewById(R.id.seekBar2);
                    final TextView txtView = (TextView) v.findViewById(R.id.intervalValue);

                    sb.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
                        @Override
                        public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                            txtView.setText(String.valueOf(progress)+ " sec");


                        }

                        @Override
                        public void onStartTrackingTouch(SeekBar seekBar) {

                        }

                        @Override
                        public void onStopTrackingTouch(SeekBar seekBar) {

                        }
                    });


                    builder2.setView(v);
                    builder2.setTitle("Interval between updates");
                    builder2.setPositiveButton(R.string.ok, new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int id) {
                            // User clicked OK button
                        }
                    });
                    builder2.setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int id) {
                            // User cancelled the dialog
                        }
                    });


                    builder2.show();

                    final Button positiveButton = builder2.getButton(DialogInterface.BUTTON_POSITIVE);
                    LinearLayout.LayoutParams positiveButtonLL = (LinearLayout.LayoutParams) positiveButton.getLayoutParams();
                    positiveButtonLL.gravity = Gravity.CENTER;
                    positiveButton.setLayoutParams(positiveButtonLL);


                    return true;

...

setting_alert_dialog.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">


    <TextView
        android:id="@+id/intervalValue"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="16dp"
        android:textColor="#FFFFFF"
        android:text="TextView" />

    <SeekBar
        android:id="@+id/seekBar2"
        style="@style/Widget.AppCompat.SeekBar.Discrete"
        android:layout_width="150dp"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="45dp"
        android:max="60"
        android:progress="3"
        android:progressTint="#FFFFFF"
        android:thumbTint="#FFFFFF" />
</RelativeLayout>

Answer 1

getButton() is a member of the class AlertDialog not AlertDialog.Builder.
if you change to:
AlertDialog alertDialog = new AlertDialog(this, R.style.SettingDialogStyle);
then you have access to alertDialog.getButton()

Alternative, after this line:

      AlertDialog.Builder builder2 = new AlertDialog.Builder(this, R.style.SettingDialogStyle);

by this:

AlertDialog alertDialog = builder2.create();

you have the alert dialog that can access getButton()

Answer 2

You can verify that getButton() is a method of AlertDialog class by taking a look at the AOSP project at

https://github.com/aosp-mirror/platform_frameworks_base/blob/master/core/java/android/app/AlertDialog.java#L239

so, the correct code should be the following:

AlertDialog dialog = builder2.show();
final Button positiveButton = dialog.getButton(DialogInterface.BUTTON_POSITIVE);