LIBGDX - Image Button - join images - eclipse

Question

I am trying to use de Image Button on LIBGDX to create a button based on two images.
Using add to second image, works fine, but have one problem.
The images are of different sizes.
Note: I am testing with the same picture to see the result
Is there a way to correct this? Using some scale to the images?
levelsTexture = new Texture(Gdx.files.internal("level1.png"));
levels = new TextureRegion(levelsTexture).split(TILE_WIDTH, TILE_HEIGHT);
ImageButton levels_image = new ImageButton(new TextureRegionDrawable(new
TextureRegion(levels[0][0])));
levels_image.add(new Image (levels[0][0]));
stage.addActor(levels_image);
levels_image.setScale(2f);
The problem:

Answer 1

ImageButton is an extension of the Table class and typically the ImageButton images are set as the background. Using the "add" method for the second image like you did might work kind of, but it behaves differently than setting the background and it also might not be what you want if you want the the second image to also change when you click the button.
The easiest way to add two images to a single ImageButton would be to simply combine the two images in Photoshop (or equivalent) and use that single image on the ImageButton.
The more advanced (and more flexible) method would be to combine the two images programmatically and use this as the background for your ImageButton. This can be done by creating a custom class which extends BaseDrawable and have it take two Images in the constructor. If you want your images stacked on top of each other, set the minHeight of your custom drawable class to be the combined height of your two images. Then override the draw method and draw your two images on top of each other like this:
#Override
public void draw(Batch batch, float x, float y, float width, float height){
img1.getDrawable().draw(batch, x, y, img1.getWidth(), img1.getHeight());
img2.getDrawable().draw(batch, x, y+img1.getHeight(), img2.getWidth(), img2.getHeight());
}
}
The ImageButton takes a Drawable in its constructor, so you can pass this object right into the button when you create it and both of your Images should appear in the button and they will be treated as one.
I've done something similar to make a background for a table using multiple Images and this method works great.

Answer 2

I wrote my own SpriteButton class in which I implement this method for scaling my textures.
private Dimension getScaledDimension(Dimension imgSize, Dimension boundary) {
int original_width = imgSize.width;
int original_height = imgSize.height;
int bound_width = boundary.width;
int bound_height = boundary.height;
int new_width = original_width;
int new_height = original_height;
// first check if we need to scale width
if (original_width > bound_width) {
//scale width to fit
new_width = bound_width;
//scale height to maintain aspect ratio
new_height = (new_width * original_height) / original_width;
}
// then check if we need to scale even with the new height
if (new_height > bound_height) {
//scale height to fit instead
new_height = bound_height;
//scale width to maintain aspect ratio
new_width = (new_height * original_width) / original_height;
}
return new Dimension(new_width, new_height);
}
Then finally you draw the texture with the output dimension as as size to draw.
sb.begin();
sb.draw(this.texture2, this.x, this.y, dim_size_new.width, dim_size_new.height);
sb.end();
So you could technically draw the second image to the size of the the first image, if the first image size is correct.
Your implementation will look different from mine but you should be able to figure it out form here on out.