libGDX Stage input handling

Question

I have an Stage class that handles touch input.

In the Screen class I set the stage as InputProcessor:

stageTest = new StageTest(new ScreenViewport());
Gdx.input.setInputProcessor(stageHUD);

But now I want to add a force to an Box2d object always a gesture input happens.

public class ActSwipe extends Actor {

    private int tmpPointer;
    private float
            tmpX,
            tmpY,
            deltaX,
            deltaY,
            rad;
    protected float
            forceX,
            forceY;


    public ActSwipe() {
        this.setName("SwipeAction");
        this.setTouchable(Touchable.enabled);
        this.addListener(new InputListener() {
            @Override
            public boolean touchDown(InputEvent event, float x, float y, int pointer, int button) {
                if(tmpPointer == 0) {
                    tmpPointer = pointer;
                    tmpX = x;
                    tmpY = y;
                }
                return true;
            }

            @Override
            public void touchUp(InputEvent event, float x, float y, int pointer, int button) {
                if (tmpPointer == pointer) {
                    tmpPointer = 0;
                    deltaX = x - tmpX;
                    deltaY = y - tmpY;
                    rad = (float) Math.atan2(deltaY, deltaX);
                    forceX = (float) Math.cos(rad);
                    forceY = (float) Math.sin(rad);
                }
            }
        });
    }

}

Take a look at this class: `com.badlogic.gdx.input.GestureDetector` and this wiki article: https://github.com/libgdx/libgdx/wiki/Gesture-detection — donfuxx, Jun 17 '15 at 21:19
Sorry wasn't looking for the Gesture listener. I whant to override the Stage input methods in an other class (Screen) like Gdx.input.InputProcessor(new InputProcessor() {override methods}) does. — , Jun 18 '15 at 16:25

Chanandler Bong · Answer 1 · 2016-02-09T12:50:04.833

You can implement InputProcessor (or extend InputAdapter) in your screen and override its methods with your code.

Then use InputMultiplexer like this:

InputMultiplexer multiplexer = new InputMultiplexer();
Gdx.input.setInputProcessor(multiplexer);
multiplexer.addProcessor(this);
multiplexer.addProcessor(stage)

In the overridden methods you need to make sure that an object that was hit is an object that should be handled by your input processor and not the one from the scene. If so, return true from the method, so the event won't be passed to the latter.

libGDX Stage input handling

1 Answers1