java - LibGDX - 自定义点击监听器？

Question

我想制作我自己的 Button 类，它将有一个 Sprite，每当我触摸它时它就会增长或旋转等，该类还将有一个 Draw 和 Update 函数。

要检查我是否触摸它，我可以检查 sprite 矩形是否包含触摸在屏幕类的 touchdown 和 touchup 方法中的位置。

我不想那样做，我想做类似 android 按钮点击监听器的东西，这可能吗？

有点像

myCoolButton.setOnClickListener(new CoolButtonClassClickListener(

public void OnTouchDown()  {

}

public void OnTouchUp()   {
}
});

可能吗？

Answer 1

当然可以，我也是这么做的。

public interface FFListener
{
    public void onClick(FFListenerButton flb);
}

和

public class FFListenerButton extends FFButton
{
    private FFListener ffListener;

    public FFListenerButton(Rectangle bounds, CharSequence text, FFListener ffListener)
    {
        super(bounds, text);
        this.ffListener = ffListener;
    }

    @Override
    protected void action()
    {
        ffListener.onClick(this);
    }
}

和

public abstract class FFButton 
{
    private Rectangle bounds;
    private CharSequence text;
    private boolean selected;
    private boolean hidden;
    private boolean active;
    private boolean disabled;

    public FFButton(Rectangle bounds, CharSequence text)
    {
        this.bounds = bounds;
        this.text = text;
        this.hidden = false;
        this.active = false;
        this.disabled = false;
    }

    protected abstract void action();

    public void execute()
    {
        if(disabled == false)
        {
            action();
        }
    }


    public boolean contains(float x, float y)
    {
        return bounds.contains(x, y);
    }

    public float x()
    {
        return bounds.x;
    }

    public float y()
    {
        return bounds.y;
    }

    public float width()
    {
        return bounds.width;
    }

    public float height()
    {
        return bounds.height;
    }

    public void drawBounds(ShapeRenderer shapeRenderer)
    {
        if(hidden != true)
        {
        shapeRenderer.rect(x(), y(), width(), height(), 0, 0, 0);
        }
    }

    public CharSequence getText()
    {
        return text;
    }

    public FFButton setText(String text)
    {
        this.text = text;
        return this;
    }

    public void drawText(SpriteBatch batch)
    {
        if(hidden != true)
        {
            Resources.bitmapFont.draw(batch, getText(), x()+(width()/8), y()+height()*0.75f); //black magic, please adjust
        }
    }

    public boolean getSelected()
    {
        return selected;
    }

    public FFButton setSelected(boolean selected)
    {
        this.selected = selected;
        return this;
    }

    public boolean isActive()
    {
        return active;
    }

    public FFButton setActive(boolean active)
    { 
        this.active = active;
        return this;
    }

    public boolean isHidden()
    {
        return hidden;
    }

    public FFButton setHidden(boolean hidden)
    {
        this.hidden = hidden;
        return this;
    }

    public Rectangle getBounds()
    {
        return bounds;
    }

    public boolean isDisabled()
    {
        return disabled;
    }

    public void setDisabled(boolean disabled)
    {
        this.disabled = disabled;
    }
}

虽然从技术上讲这使用了一个 Rectangle 并使用 ShapeRenderer 来渲染它，但将它换成 Sprite 确实不难。之后，您可以使用 contains 询问点击是否包含，如果是，则从外部调用 execute()。

这样创建:

backButton = new FFListenerButton(new Rectangle(400, 20, 60, 30), "Back", this);

并像这样处理事件:

@Override
public void onClick(FFListenerButton clb)
{
    if(clb == backButton)
    {
        backButtonPressed();
    }
    else if(clb == selectButton)
    {
        ...
    }
}

这使用我的 AbstractMenuScreen 类将事件委托(delegate)给按钮(如果它们被单击):

public abstract class AbstractMenuScreen extends BaseScreen
{
    protected List<FFButton> buttons;

    public AbstractMenuScreen(List<FFButton> buttons)
    {
        this.buttons = buttons; 
    }

    @Override
    public void render(float delta)
    {
        Gdx.gl.glClearColor(0, 0, 0, 1);
        Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);

        Resources.batch.setProjectionMatrix(Resources.normalProjection);

        Resources.batch.begin();
        for(int i = 0; i < buttons.size(); i++)
        {
            FFButton b = buttons.get(i);
            if(b.isHidden() != true)
            {
                b.drawText(Resources.batch);
            }
        }

        Resources.batch.end();

        Resources.shapeRenderer.setColor(Color.WHITE);
        Resources.shapeRenderer.begin(ShapeType.Line);
        for(int i = 0; i < buttons.size(); i++)
        {
            FFButton b = buttons.get(i);
            if(b.isHidden() != true)
            {
                b.drawBounds(Resources.shapeRenderer);
            }
        }
        Resources.shapeRenderer.end();

        Resources.shapeRenderer.setColor(Color.RED);
        Resources.shapeRenderer.begin(ShapeType.Line);
        for(int i = 0; i < buttons.size(); i++)
        {
            FFButton b = buttons.get(i);
            if(b.isHidden() != true)
            {
                if(b.isActive() == true)
                {
                    b.drawBounds(Resources.shapeRenderer);
                }
            }
        }
        Resources.shapeRenderer.end();

        Resources.shapeRenderer.setColor(Color.MAGENTA);
        Resources.shapeRenderer.begin(ShapeType.Line);
        for(int i = 0; i < buttons.size(); i++)
        {
            FFButton b = buttons.get(i);
            if(b.isHidden() != true)
            {
                if(b.getSelected() == true)
                {
                    b.drawBounds(Resources.shapeRenderer);
                }
            }
        }
        Resources.shapeRenderer.end();
    }

    @Override
    public void show()
    {
        Gdx.input.setInputProcessor(this);
    }

    @Override
    public boolean touchDown(int screenX, int screenY, int pointer, int button)
    {
        float pointerX = InputTransform.getCursorToModelX(windowWidth, screenX);
        float pointerY = InputTransform.getCursorToModelY(windowHeight, screenY);
        for(int i = 0; i < buttons.size(); i++)
        {
            if(buttons.get(i).contains(pointerX, pointerY))
            {
                if(buttons.get(i).isHidden() != true)
                {
                    buttons.get(i).setSelected(true);
                }
            }
        }
        return true;
    }

    @Override
    public boolean touchUp(int screenX, int screenY, int pointer, int button)
    {
        float pointerX = InputTransform.getCursorToModelX(windowWidth, screenX);
        float pointerY = InputTransform.getCursorToModelY(windowHeight, screenY);
        for(int i = 0; i < buttons.size(); i++)
        {
            if(buttons.get(i).contains(pointerX, pointerY) && buttons.get(i).getSelected())
            {
                buttons.get(i).execute();
            }
            buttons.get(i).setSelected(false);
        }
        return true;
    }
    ...

然后你这样扩展:

public class ServerClientPickScreen extends AbstractMenuScreen implements FFListener
{
    private FFButton backButton;
    private FFButton clientButton;
    private FFButton serverButton;

    public ServerClientPickScreen()
    {
        super(new ArrayList<FFButton>());
        backButton = new FFListenerButton(new Rectangle(400, 20, 60, 30), "Back", this);
        clientButton = new FFListenerButton(new Rectangle(260, 140, 80, 30), "Client", this);
        serverButton = new FFListenerButton(new Rectangle(140, 140, 80, 30), "Server", this);
        buttons.add(backButton);
        buttons.add(clientButton);
        buttons.add(serverButton);
 ....