Gli snippet di codice provenienti da altre risposte funzionano, ma non è sempre ovvio dove inserirli nel codice, soprattutto se si sta utilizzando un tutorial di dialogo ufficialeAlertDialog.Builder seguito e perché non utilizza o .final AlertDialog ...alertDialog.show()
alertDialog.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
È preferibile
InputMethodManager imm = (InputMethodManager) getSystemService(Context.INPUT_METHOD_SERVICE);
imm.toggleSoftInput(InputMethodManager.SHOW_FORCED,0);
Poiché SOFT_INPUT_STATE_ALWAYS_VISIBLE nasconderà la tastiera se lo stato attivo si sposta dall'EditText, dove SHOW_FORCED manterrà la tastiera visualizzata fino a quando non viene esplicitamente ignorata, anche se l'utente torna alla schermata iniziale o visualizza le app recenti.
Di seguito è riportato un codice funzionante per un AlertDialog creato utilizzando un layout personalizzato con un EditText definito in XML. Imposta inoltre la tastiera per avere un tasto "go" e consente di attivare il pulsante positivo.
alert_dialog.xml:
<RelativeLayout
android:id="@+id/dialogRelativeLayout"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<!-- android:imeOptions="actionGo" sets the keyboard to have a "go" key instead of a "new line" key. -->
<!-- android:inputType="textUri" disables spell check in the EditText and changes the "go" key from a check mark to an arrow. -->
<EditText
android:id="@+id/editText"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:layout_marginLeft="4dp"
android:layout_marginRight="4dp"
android:layout_marginBottom="16dp"
android:imeOptions="actionGo"
android:inputType="textUri"/>
</RelativeLayout>
AlertDialog.java:
import android.app.Activity;
import android.app.Dialog;
import android.content.DialogInterface;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.DialogFragment;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatDialogFragment;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.WindowManager;
import android.widget.EditText;
public class CreateDialog extends AppCompatDialogFragment {
// The public interface is used to send information back to the activity that called CreateDialog.
public interface CreateDialogListener {
void onCreateDialogCancel(DialogFragment dialog);
void onCreateDialogOK(DialogFragment dialog);
}
CreateDialogListener mListener;
// Check to make sure that the activity that called CreateDialog implements both listeners.
public void onAttach(Activity activity) {
super.onAttach(activity);
try {
mListener = (CreateDialogListener) activity;
} catch (ClassCastException e) {
throw new ClassCastException(activity.toString() + " must implement CreateDialogListener.");
}
}
// onCreateDialog requires @NonNull.
@Override
@NonNull
public Dialog onCreateDialog(Bundle savedInstanceState) {
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(getActivity());
LayoutInflater customDialogInflater = getActivity().getLayoutInflater();
// Setup dialogBuilder.
alertDialogBuilder.setTitle(R.string.title);
alertDialogBuilder.setView(customDialogInflater.inflate(R.layout.alert_dialog, null));
alertDialogBuilder.setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
mListener.onCreateDialogCancel(CreateDialog.this);
}
});
alertDialogBuilder.setPositiveButton(R.string.ok, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
mListener.onCreateDialogOK(CreateDialog.this);
}
});
// Assign the resulting built dialog to an AlertDialog.
final AlertDialog alertDialog = alertDialogBuilder.create();
// Show the keyboard when the dialog is displayed on the screen.
alertDialog.getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE);
// We need to show alertDialog before we can setOnKeyListener below.
alertDialog.show();
EditText editText = (EditText) alertDialog.findViewById(R.id.editText);
// Allow the "enter" key on the keyboard to execute "OK".
editText.setOnKeyListener(new View.OnKeyListener() {
public boolean onKey(View v, int keyCode, KeyEvent event) {
// If the event is a key-down event on the "enter" button, select the PositiveButton "OK".
if ((event.getAction() == KeyEvent.ACTION_DOWN) && (keyCode == KeyEvent.KEYCODE_ENTER)) {
// Trigger the create listener.
mListener.onCreateDialogOK(CreateDialog.this);
// Manually dismiss alertDialog.
alertDialog.dismiss();
// Consume the event.
return true;
} else {
// If any other key was pressed, do not consume the event.
return false;
}
}
});
// onCreateDialog requires the return of an AlertDialog.
return alertDialog;
}
}