I have a DialogFragment with a custom view which contains two text fields where the user is to input their username and password. When the positive button is clicked, I want to validate that the user actually did input something before dismissing the dialog.
public class AuthenticationDialog extends DialogFragment {
public Dialog onCreateDialog(Bundle savedInstanceState) {
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
LayoutInflater inflater = getActivity().getLayoutInflater();
builder.setView(inflater.inflate(R.layout.authentication_dialog, null))
.setPositiveButton(getResources().getString(R.string.login), new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// TODO
}
})
.setNegativeButton(getResources().getString(R.string.reset), new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// TODO
}
});
return builder.create();
}
}
So how can I prevent the dialog from dismissing? Is there some method I should override?
Override the default button handlers in OnStart() to do this.
@Override
public Dialog onCreateDialog(Bundle savedInstanceState)
{
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
builder.setMessage("Test for preventing dialog close");
builder.setPositiveButton("Test",
new DialogInterface.OnClickListener()
{
@Override
public void onClick(DialogInterface dialog, int which)
{
//Do nothing here because we override this button later to change the close behaviour.
//However, we still need this because on older versions of Android unless we
//pass a handler the button doesn't get instantiated
}
});
return builder.create();
}
@Override
public void onStart()
{
super.onStart(); //super.onStart() is where dialog.show() is actually called on the underlying dialog, so we have to do it after this point
AlertDialog d = (AlertDialog)getDialog();
if(d != null)
{
Button positiveButton = (Button) d.getButton(Dialog.BUTTON_POSITIVE);
positiveButton.setOnClickListener(new View.OnClickListener()
{
@Override
public void onClick(View v)
{
Boolean wantToCloseDialog = false;
//Do stuff, possibly set wantToCloseDialog to true then...
if(wantToCloseDialog)
dismiss();
//else dialog stays open. Make sure you have an obvious way to close the dialog especially if you set cancellable to false.
}
});
}
}
See my answer here https://stackoverflow.com/a/15619098/579234 for more explanation and examples on other dialog types too.