EditTextPreference - only numeric value inputType - isn't working

Answer 1

android.support.v7.preference.EditTextPreference doesn't contain getEditText() method.

But we can extends android.support.v7.preference.EditTextPreferenceDialogFragmentCompat to set inputType.

public class EditTextPreferenceDialogFragmentCompat extends android.support.v7.preference.EditTextPreferenceDialogFragmentCompat {

private EditText mEditText;
private int mInputType;

public static EditTextPreferenceDialogFragmentCompat newInstance(String key, int inputType) {
    EditTextPreferenceDialogFragmentCompat fragment = new EditTextPreferenceDialogFragmentCompat();
    Bundle b = new Bundle(2);
    b.putString("key", key);
    b.putInt("inputType", inputType);
    fragment.setArguments(b);
    return fragment;
}

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    mInputType = this.getArguments().getInt("inputType");
}

protected void onBindDialogView(View view) {
    this.mEditText = view.findViewById(android.R.id.edit);
    mEditText.setInputType(mInputType);
    super.onBindDialogView(view);
}

}

Then make your activity implements PreferenceFragmentCompat.OnPreferenceDisplayDialogCallback

Use your EditTextPreferenceDialogFragmentCompat instead of android.support.v7.preference.EditTextPreferenceDialogFragmentCompat

public boolean onPreferenceDisplayDialog(@NonNull PreferenceFragmentCompat preferenceFragmentCompat, Preference preference) {
String key = preference.getKey();
if (/**show your dialog*/) {
    EditTextPreferenceDialogFragmentCompat f = EditTextPreferenceDialogFragmentCompat.newInstance(preference.getKey(), InputType.TYPE_CLASS_NUMBER | InputType.TYPE_NUMBER_FLAG_SIGNED);
    f.setTargetFragment(this, 0);
    f.show(getFragmentManager(), "android.support.v14.preference.PreferenceFragment.DIALOG");
    return true;
}
return false;

}

just use android.support.v7.preference.EditTextPreference in xml