Java tutorial
/******************************************************************************* * Copyright 2011 See AUTHORS file. * * 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.badlogic.gdx.scenes.scene2d.ui; import static com.badlogic.gdx.scenes.scene2d.actions.Actions.*; import com.badlogic.gdx.Input.Keys; import com.badlogic.gdx.math.Interpolation; import com.badlogic.gdx.scenes.scene2d.Action; import com.badlogic.gdx.scenes.scene2d.Actor; import com.badlogic.gdx.scenes.scene2d.Group; import com.badlogic.gdx.scenes.scene2d.InputEvent; import com.badlogic.gdx.scenes.scene2d.InputListener; import com.badlogic.gdx.scenes.scene2d.Stage; import com.badlogic.gdx.scenes.scene2d.actions.Actions; import com.badlogic.gdx.scenes.scene2d.ui.Label.LabelStyle; import com.badlogic.gdx.scenes.scene2d.ui.TextButton.TextButtonStyle; import com.badlogic.gdx.scenes.scene2d.utils.ChangeListener; import com.badlogic.gdx.scenes.scene2d.utils.FocusListener; import com.badlogic.gdx.utils.ObjectMap; import com.badlogic.gdx.utils.viewport.Viewport; /** Displays a dialog, which is a modal window containing a content table with a button table underneath it. Methods are provided * to add a label to the content table and buttons to the button table, but any widgets can be added. When a button is clicked, * {@link #result(Object)} is called and the dialog is removed from the stage. * @author Nathan Sweet */ public class Dialog extends Window { Table contentTable, buttonTable; private Skin skin; ObjectMap<Actor, Object> values = new ObjectMap(); boolean cancelHide; Actor previousKeyboardFocus, previousScrollFocus; FocusListener focusListener; protected InputListener ignoreTouchDown = new InputListener() { public boolean touchDown(InputEvent event, float x, float y, int pointer, int button) { event.cancel(); return false; } }; public Dialog(String title, Skin skin) { super(title, skin.get(WindowStyle.class)); this.skin = skin; initialize(); } public Dialog(String title, Skin skin, String windowStyleName) { super(title, skin.get(windowStyleName, WindowStyle.class)); setSkin(skin); this.skin = skin; initialize(); } public Dialog(String title, WindowStyle windowStyle) { super(title, windowStyle); initialize(); } private void initialize() { setModal(true); defaults().space(6); add(contentTable = new Table(skin)).expand().fill(); row(); add(buttonTable = new Table(skin)); contentTable.defaults().space(6); buttonTable.defaults().space(6); buttonTable.addListener(new ChangeListener() { public void changed(ChangeEvent event, Actor actor) { if (!values.containsKey(actor)) return; while (actor.getParent() != buttonTable) actor = actor.getParent(); result(values.get(actor)); if (!cancelHide) hide(); cancelHide = false; } }); focusListener = new FocusListener() { public void keyboardFocusChanged(FocusEvent event, Actor actor, boolean focused) { if (!focused) focusChanged(event); } public void scrollFocusChanged(FocusEvent event, Actor actor, boolean focused) { if (!focused) focusChanged(event); } private void focusChanged(FocusEvent event) { Stage stage = getStage(); if (isModal && stage != null && stage.getRoot().getChildren().size > 0 && stage.getRoot().getChildren().peek() == Dialog.this) { // Dialog is top most actor. Actor newFocusedActor = event.getRelatedActor(); if (newFocusedActor != null && !newFocusedActor.isDescendantOf(Dialog.this) && !(newFocusedActor.equals(previousKeyboardFocus) || newFocusedActor.equals(previousScrollFocus))) event.cancel(); } } }; } protected void setStage(Stage stage) { if (stage == null) addListener(focusListener); else removeListener(focusListener); super.setStage(stage); } public Table getContentTable() { return contentTable; } public Table getButtonTable() { return buttonTable; } /** Adds a label to the content table. The dialog must have been constructed with a skin to use this method. */ public Dialog text(String text) { if (skin == null) throw new IllegalStateException( "This method may only be used if the dialog was constructed with a Skin."); return text(text, skin.get(LabelStyle.class)); } /** Adds a label to the content table. */ public Dialog text(String text, LabelStyle labelStyle) { return text(new Label(text, labelStyle)); } /** Adds the given Label to the content table */ public Dialog text(Label label) { contentTable.add(label); return this; } /** Adds a text button to the button table. Null will be passed to {@link #result(Object)} if this button is clicked. The dialog * must have been constructed with a skin to use this method. */ public Dialog button(String text) { return button(text, null); } /** Adds a text button to the button table. The dialog must have been constructed with a skin to use this method. * @param object The object that will be passed to {@link #result(Object)} if this button is clicked. May be null. */ public Dialog button(String text, Object object) { if (skin == null) throw new IllegalStateException( "This method may only be used if the dialog was constructed with a Skin."); return button(text, object, skin.get(TextButtonStyle.class)); } /** Adds a text button to the button table. * @param object The object that will be passed to {@link #result(Object)} if this button is clicked. May be null. */ public Dialog button(String text, Object object, TextButtonStyle buttonStyle) { return button(new TextButton(text, buttonStyle), object); } /** Adds the given button to the button table. */ public Dialog button(Button button) { return button(button, null); } /** Adds the given button to the button table. * @param object The object that will be passed to {@link #result(Object)} if this button is clicked. May be null. */ public Dialog button(Button button, Object object) { buttonTable.add(button); setObject(button, object); return this; } /** {@link #pack() Packs} the dialog and adds it to the stage with custom action which can be null for instant show */ public Dialog show(Stage stage, Action action) { clearActions(); removeCaptureListener(ignoreTouchDown); previousKeyboardFocus = null; Actor actor = stage.getKeyboardFocus(); if (actor != null && !actor.isDescendantOf(this)) previousKeyboardFocus = actor; previousScrollFocus = null; actor = stage.getScrollFocus(); if (actor != null && !actor.isDescendantOf(this)) previousScrollFocus = actor; pack(); stage.addActor(this); stage.setKeyboardFocus(this); stage.setScrollFocus(this); if (action != null) addAction(action); return this; } /** {@link #pack() Packs} the dialog and adds it to the stage, centered with default fadeIn action */ public Dialog show(Stage stage) { show(stage, sequence(Actions.alpha(0), Actions.fadeIn(0.4f, Interpolation.fade))); setPosition(Math.round((stage.getWidth() - getWidth()) / 2), Math.round((stage.getHeight() - getHeight()) / 2)); return this; } /** Hides the dialog with the given action and then removes it from the stage. */ public void hide(Action action) { Stage stage = getStage(); if (stage != null) { removeListener(focusListener); if (previousKeyboardFocus != null && previousKeyboardFocus.getStage() == null) previousKeyboardFocus = null; Actor actor = stage.getKeyboardFocus(); if (actor == null || actor.isDescendantOf(this)) stage.setKeyboardFocus(previousKeyboardFocus); if (previousScrollFocus != null && previousScrollFocus.getStage() == null) previousScrollFocus = null; actor = stage.getScrollFocus(); if (actor == null || actor.isDescendantOf(this)) stage.setScrollFocus(previousScrollFocus); } if (action != null) { addCaptureListener(ignoreTouchDown); addAction(sequence(action, Actions.removeListener(ignoreTouchDown, true), Actions.removeActor())); } else remove(); } /** Hides the dialog. Called automatically when a button is clicked. The default implementation fades out the dialog over 400 * milliseconds and then removes it from the stage. */ public void hide() { hide(sequence(fadeOut(0.4f, Interpolation.fade), Actions.removeListener(ignoreTouchDown, true), Actions.removeActor())); } public void setObject(Actor actor, Object object) { values.put(actor, object); } /** If this key is pressed, {@link #result(Object)} is called with the specified object. * @see Keys */ public Dialog key(final int keycode, final Object object) { addListener(new InputListener() { public boolean keyDown(InputEvent event, int keycode2) { if (keycode == keycode2) { result(object); if (!cancelHide) hide(); cancelHide = false; } return false; } }); return this; } /** Called when a button is clicked. The dialog will be hidden after this method returns unless {@link #cancel()} is called. * @param object The object specified when the button was added. */ protected void result(Object object) { } public void cancel() { cancelHide = true; } }