How do libgdx detect keyboard presence

Question

When writing in the Textfield, I need my textfield to move upwards in order to let the textfield be visible when the keyboard pops up.

Does libgdx have some kind of

Answer 1

I know I'm answering to an old thread, but I was googling to find an answer to this question but couldn't find it anywhere. Now I have created a solution myself. Here is how to do it on Android in an elegant way :) I'm creating an ApplicationBundle to bundle interfaces to add platform specific things. You can do this on iOS too if you want to make use of RoboVM.

My solution:

create a SizeChangeListener interface in the core project:

public interface SizeChangeListener {
    public void onSizeChange(float width, float height);
}

create a View interface in the core project:

public interface View {
    public void onSizeChange(float width, float height);
    public void addListener(SizeChangeListener sizeChangeListener);
    public float getWidth();
    public float getHeight();
}

create an AndroidView implementing the View interface:

public class AndroidView implements View {

    private ArrayList listeners = new ArrayList();
    private float width, height;
    public AndroidView(int width, int height) {
        this.width = width;
        this.height = height;
    }

    public void addListener(SizeChangeListener listener) {
        listeners.add(listener);
    }

    public void onSizeChange(float width, float height) {
        this.width = width;
        this.height = height;
        for(SizeChangeListener listener : listeners)
            listener.onSizeChange(width, height);
    }

    public float getWidth() {
        return width;
    }

    public float getHeight() {
        return height;
    }

}

create an ApplicationBundle in the core project

public class ApplicationBundle {

    private final View view;

    public ApplicationBundle(View view) {
        this.view = view;
    }

    public View getView() {
        return view;
    }
}

Make the necessary imports from the core project. In the AndroidLauncher in the Android project add the following:

public class AndroidLauncher extends AndroidApplication {

    private View rootView;
    private AndroidView androidView;
    private int width, height;

    @Override
    protected void onCreate (Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        AndroidApplicationConfiguration config = new AndroidApplicationConfiguration();
        rootView = this.getWindow().getDecorView().getRootView();
        Rect rect = new Rect();
        rootView.getWindowVisibleDisplayFrame(rect);
        width = rect.width();
        height = rect.height();
        androidView = new AndroidView(width, height);

        rootView.addOnLayoutChangeListener(new OnLayoutChangeListener() {

            @Override
            public void onLayoutChange(View v, int left, int top, int right,
                    int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {

                Rect rect = new Rect();
                rootView.getWindowVisibleDisplayFrame(rect);

                if(!(width == rect.width() && height == rect.height())) {
                    width = rect.width();
                    height = rect.height();
                    androidView.onSizeChange(width, height);
                }
            }

        }); 

        initialize(new DigMeApp(new ApplicationBundle(androidView)), config);
    }
}

In your main MyApp in the core project in the create() method add a SizeChangeListener implementation to the view you've got from the constructor.

public class MyApp extends Game { // or ApplicationAdapter
    private View view;
    private Stage stage;
    // your own variables

    public MyApp(ApplicationBundle applicationBundle) {
        view = applicationBundle.getView();
    }

    @Override
    public void create () {
        stage = new Stage();
        // add some textfields
    final TextField tf1 = new TextField("", skin);
    final TextField tf2 = new TextField("", skin);

    tf1.setWidth((float)view.getWidth() * 0.6f);
    tf2.setWidth((float)view.getWidth() * 0.6f);
    tf1.setHeight((float)view.getHeight() * 0.05f);
    tf2.setHeight((float)view.getHeight() * 0.05f);
        view.addListener(new SizeChangeListener() {         
            @Override
            public void onSizeChange(float width, float height) {
                Gdx.app.log("INFO", "Visible area: " + width + "   " + height);
                Gdx.app.log("INFO", "Stage area: " + stage.getWidth() + "   " + stage.getHeight());
                float keyboardHeight = getKeyboardHeight();

// MOVE THEM OUT OF THE WAY :)

                tf1.addAction(Actions.moveTo(width / 2 - tf1.getWidth() / 2.0f, keyboardHeight + (6 * (height / 8)), 1, Interpolation.sineOut));
                tf2.addAction(Actions.moveTo(width / 2 - tf2.getWidth() / 2.0f, keyboardHeight + (7 * (height / 8)), 1, Interpolation.sineOut));


//              Gdx.gl20.
//              tf.setPosition(width / 2 - (tf.getWidth() / 2.0f), 0);
            }
        });
}

Perhaps create a little keyboard heigt method like I did:

private float getKeyboardHeight() {
        return stage.getHeight() - view.getHeight();
    }