使用libgdx,如何将文本和图像添加到ScrollPane？

Question

这是一段代码片段.

itemList = new List(skin, "ariel.32.white");
String[] tmpInv = new String[b+1];
tmpInv[0] = "<Empty>";
a++;
for (Entry<String, String> entry : inventoryItems.entrySet()) {
    tmpInv[a] = entry.getKey(); 
    a++;
    //String key = entry.getKey();
    //Object value = entry.getValue();
    // ...
}
Arrays.sort(tmpInv);

itemList.setItems(tmpInv);

inventoryPane  = new ScrollPane(itemList, skin);

这是我得到的,它工作正常.我想在每个项目前面添加描述性图标,但我似乎无法让它工作.我还需要一些方法来获取添加后所选内容的名称.目前我用

itemlist.getSelectedIndex();

Answer 1

据我所知,您不能使用列表小部件来添加图像或表格或文本以外的任何内容.但是,您可以创建一个表并将Drawable背景更改为新的纹理,该纹理可以模拟某些事件发生时列表的效果(如mouseMove事件).然后,您可以将该表添加到ScrollPane中,该ScrollPane可以处理您的滚动事件.

这将带您进行一些编码,但这是一个我为您掀起的工作示例:

package <some package>;

import com.badlogic.gdx.Game;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.Screen;
import com.badlogic.gdx.graphics.GL20;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.g2d.TextureRegion;
import com.badlogic.gdx.scenes.scene2d.Event;
import com.badlogic.gdx.scenes.scene2d.Stage;
import com.badlogic.gdx.scenes.scene2d.ui.Image;
import com.badlogic.gdx.scenes.scene2d.ui.Label;
import com.badlogic.gdx.scenes.scene2d.ui.ScrollPane;
import com.badlogic.gdx.scenes.scene2d.ui.Skin;
import com.badlogic.gdx.scenes.scene2d.ui.Table;
import com.badlogic.gdx.scenes.scene2d.utils.FocusListener;
import com.badlogic.gdx.scenes.scene2d.utils.TextureRegionDrawable;

public class ScrollScreenTest implements Screen{
    Game game;
    ScrollPane scrollpane;
    Skin skin;
    Stage stage;
    Table container, table1, table2, table3;
    Texture texture1, texture2, texture3;

    public ScrollScreenTest(Game game){
        this.game = game;
    }
    @Override
    public void render(float delta) {
        Gdx.gl.glClearColor(0, 0, 0, 1);    //sets up the clear color (background color) of the screen.
        Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);  //instructs openGL to actually clear the screen to the newly set clear color.
        stage.draw();
        stage.act(delta);

    }

    @Override
    public void resize(int width, int height) {
    }

    @Override
    public void show() {

        // setup skin
        skin = new Skin(Gdx.files.internal("data/uiskin.json"));

        texture1 = new Texture(Gdx.files.internal("iron_axe.png"));
        texture2 = new Texture(Gdx.files.internal("iron_dagger.png"));
        texture3 = new Texture(Gdx.files.internal("iron_sword.png"));

        // table that holds the scroll pane
        container = new Table();
        container.setWidth(320f);
        container.setHeight(300f);

        // tables that hold the data you want to display
        table1 = new Table(skin);
        table1.add(new Image(texture1)).expandY().fillY();
        table1.add(new Label("", skin)).width(10f).expandY().fillY();// a spacer
        table1.add(new Label("Look at this axe I stole!", skin)).expandY().fillY();

        table2 = new Table(skin);
        table2.add(new Image(texture2)).expandY().fillY();
        table2.add(new Label("", skin)).width(10f).expandY().fillY();// a spacer
        table2.add(new Label("So dagger, much pointy.", skin)).expandY().fillY();

        table3 = new Table(skin);
        table3.add(new Image(texture3)).expandY().fillY();
        table3.add(new Label("", skin)).width(10f).expandY().fillY();// a spacer
        table3.add(new Label("Valyrian steel..", skin)).expandY().fillY();


        //inner table that is used as a makeshift list.
        Table innerContainer = new Table();
        innerContainer.add(table1).expand().fill();
        innerContainer.row();
        innerContainer.add(table2).expand().fill();
        innerContainer.row();
        innerContainer.add(table3).expand().fill();

        // create the scrollpane
        scrollpane = new ScrollPane(innerContainer);

        //add the scroll pane to the container
        container.add(scrollpane).fill().expand();

        // setup stage
        stage = new Stage();

        // add container to the stage
        stage.addActor(container);

        // setup input processor (gets clicks and stuff)
        Gdx.input.setInputProcessor(stage);

        // setup a listener for the tables with out data

        table1.addListener(new FocusListener(){
            @Override
            public boolean handle(Event event){

            if (event.toString().equals("mouseMoved")){
                table1.background(new TextureRegionDrawable(new TextureRegion(new Texture("gray.png"))));
                return false;
            }
            else if(event.toString().equals("exit")){
                //table1.setBackground(null);
                //table1.background("");
                table1.setBackground(null, false);

                return false;
            }
                return true;
            }

        });
        table2.addListener(new FocusListener(){
            @Override
            public boolean handle(Event event){

            if (event.toString().equals("mouseMoved")){
                table2.background(new TextureRegionDrawable(new TextureRegion(new Texture("gray.png"))));
                return false;
            }
            else if(event.toString().equals("exit")){
                //table1.setBackground(null);
                //table1.background("");
                table2.setBackground(null, false);

                return false;
            }
                return true;
            }

        });
        table3.addListener(new FocusListener(){
            @Override
            public boolean handle(Event event){

            if (event.toString().equals("mouseMoved")){
                table3.background(new TextureRegionDrawable(new TextureRegion(new Texture("gray.png"))));
                return false;
            }
            else if(event.toString().equals("exit")){
                //table1.setBackground(null);
                //table1.background("");
                table3.setBackground(null, false);

                return false;
            }
                return true;
            }

        });
    }

    @Override
    public void hide() {
    }

    @Override
    public void pause() {
    }

    @Override
    public void resume() {
    }

    @Override
    public void dispose() {
    }

}

}