我是java和libgdx的新手,我想创建一个主菜单屏幕,有人可以给我一个简单的例子吗?
答案 0 :(得分:18)
你所要求的是非常广泛的,它涉及许多元素,如创建按钮,皮肤,设置表等。无论如何你应该使用屏幕,添加一个舞台并添加演员到舞台。最终,您需要将Listeners添加到按钮actor以切换屏幕。这是我为你做的一个:
public class TestScreen implements Screen{
private SpriteBatch batch;
protected Stage stage;
private Viewport viewport;
private OrthographicCamera camera;
private TextureAtlas atlas;
protected Skin skin;
public TestScreen()
{
atlas = new TextureAtlas("skin.atlas");
skin = new Skin(Gdx.files.internal("skin.json"), atlas);
batch = new SpriteBatch();
camera = new OrthographicCamera();
viewport = new FitViewport(Constants.WorldWidth, Constants.WorldHeight, camera);
viewport.apply();
camera.position.set(camera.viewportWidth / 2, camera.viewportHeight / 2, 0);
camera.update();
stage = new Stage(viewport, batch);
}
@Override
public void show() {
//Stage should controll input:
Gdx.input.setInputProcessor(stage);
//Create Table
Table mainTable = new Table();
//Set table to fill stage
mainTable.setFillParent(true);
//Set alignment of contents in the table.
mainTable.top();
//Create buttons
TextButton playButton = new TextButton("Play", skin);
TextButton optionsButton = new TextButton("Options", skin);
TextButton exitButton = new TextButton("Exit", skin);
//Add listeners to buttons
playButton.addListener(new ClickListener(){
@Override
public void clicked(InputEvent event, float x, float y) {
((Game)Gdx.app.getApplicationListener()).setScreen(new PlayScreen());
}
});
exitButton.addListener(new ClickListener(){
@Override
public void clicked(InputEvent event, float x, float y) {
Gdx.app.exit();
}
});
//Add buttons to table
mainTable.add(playButton);
mainTable.row();
mainTable.add(optionsButton);
mainTable.row();
mainTable.add(exitButton);
//Add table to stage
stage.addActor(mainTable);
}
@Override
public void render(float delta) {
Gdx.gl.glClearColor(.1f, .12f, .16f, 1);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
stage.act();
stage.draw();
}
@Override
public void resize(int width, int height) {
viewport.update(width, height);
camera.position.set(camera.viewportWidth / 2, camera.viewportHeight / 2, 0);
camera.update();
}
@Override
public void pause() {
}
@Override
public void resume() {
}
@Override
public void hide() {
}
@Override
public void dispose() {
skin.dispose();
atlas.dispose();
}
}
我称之为的方法是稍微更改初始类。
//Let the class extend from game
public class MyGame extends Game()
{
//Delete everything in it and leave a create() with a single line
@Override
public void create() {
setScreen(new MenuScreen());
}
}
当然,要使上述代码正常工作,您需要设置Skin
和Atlas
来绘制按钮。但是,您可以只添加图像和字体并手动创建按钮。无论如何,我只是answered a question,我正在深入探讨如何创建Skin
和Atlas
。
编辑虽然已经询问了菜单类的示例,但用户询问者实际上只需知道如何从屏幕切换到屏幕。有点尴尬但是不可思议地写了上面的代码只花了几分钟;)。
您始终可以使用ApplicationListener
从任意位置访问Gdx.app.getApplicationListener
。您可以将其转换为Game
以访问setScreen
。
((Game)Gdx.app.getApplicationListener()).setScreen(new GameScreen());
或者您可以手动传递初始Game对象或applicationListener。确保新屏幕接受游戏对象。
public class MenuScreen
{
private Game gameObject;
public MenuScreen(Game gameObject)
{
this.gameObject = gameObject;
}
private void someMethod()
{
//Switches to a new MenuScreen...
//useless in most cases but you get the idea
gameObject.setScreen(new MenuScreen(gameObject);
}
}