/*
* Copyright 2000-2009 JetBrains s.r.o.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.intellij.openapi.ui.popup;
import org.jetbrains.annotations.Nullable;
/**
* Base interface for a single step (submenu) of a popup, displaying a list of items or a single level of a tree structure.
*
* @see ListPopupStep
* @see TreePopupStep
* @param <T> the type of the objects contained in the list or tree structure.
* @since 6.0
*/
public interface PopupStep<T> {
PopupStep FINAL_CHOICE = null;
/**
* Returns the title of list.
*
* @return the title of the list.
*/
@Nullable
String getTitle();
/**
* Handles the selection of an item in the list.
*
* @param selectedValue the selected item.
* @param finalChoice If true, the action associated with the selected item should be displayed. If false and the selected item has
* a submenu, the popup step for the submenu should be returned.
* @return the substep to be displayed, or {@link #FINAL_CHOICE} if the popup should be closed after the item has been selected.
* @see #hasSubstep
*/
@Nullable
PopupStep onChosen(T selectedValue, final boolean finalChoice);
/**
* Checks if the specified item in the list has an associated substep.
*
* @param selectedValue the value to check for substep presence.
* @return true if the value has a substep, false otherwise.
*/
boolean hasSubstep(T selectedValue);
/**
* Called when the popup showing this step is canceled.
*/
void canceled();
/**
* Returns true if items in the list can be selected by pressing a mnemonic character. If this method returns true,
* {@link #isSpeedSearchEnabled()} must return false.
*
* @return true if navigation by mnemonics is enabled, false otherwise.
* @see #getMnemonicNavigationFilter()
*/
boolean isMnemonicsNavigationEnabled();
/**
* Returns the class supporting navigation by mnemonics in a popup.
*
* @return the mnemonics navigation filter instance, or null if navigation by mnemonics is not supported.
* @see #isMnemonicsNavigationEnabled()
*/
@Nullable
MnemonicNavigationFilter<T> getMnemonicNavigationFilter();
/**
* Returns true if items in the list can be selected by typing part of an item's text. If this method returns true,
* {@link #isMnemonicsNavigationEnabled()} must return false.
*
* @return true if speed search is enabled, false otherwise.
*/
boolean isSpeedSearchEnabled();
/**
* Returns the class supporting speed search in a popup.
*
* @return the speed search filter instance, or null if speed search is not supported.
* @see #isSpeedSearchEnabled()
*/
@Nullable
SpeedSearchFilter<T> getSpeedSearchFilter();
/**
* Returns true if the submenu for the first selectable item should be displayed automatically when the item has a submenu.
*
* @return true if the submenu for the first selectable item should be displayed automatically, false otherwise.
*/
boolean isAutoSelectionEnabled();
/**
* @return runnable to be executed when final step is chosen
*/
@Nullable
Runnable getFinalRunnable();
}