Search code examples
androidunity-game-enginetouch-eventvertical-scrolling

Unity: Vertical Group Layout Scroll doesn't work with Android

I'm doing a scrollable list of values.

I did it using an Item template setted up with Layout Element, nested in a Vertical Layout Group object.

The Item Template is composed by an image and a text description.

The script that i use to populate the list is an easy for:

for (int i = 0; i < details.Count && i < LenSize; i++){
    Transform transf = Instantiate(template, container);
    RectTransform trasnf2 = transf.GetComponent<RectTransform>();

    height = -3 * i;

    trasnf2.anchoredPosition = new Vector2(0, height);
    transf.gameObject.SetActive(true);

    transf.Find("Image").GetComponent<Text>().text = details[i].image;
    transf.Find("Desc").GetComponent<Text>().text = 
    details[i].description;
}

All works properly when I run the app from my PC, I'm able to scroll the list by "left click + drag up/down" or mouse scroll wheel.

My problem appears when i build the app and run it from my android device, i not able to scroll the list with the touchscreen. (Touchscreen inputs work fine, I have some button and they work)

Can someone help me with my problem?

I found that I can use Input manager to catch input event... but I not sure how use it to "scroll" on Android, because if i change offset of object with Vertical Layout Group, I move the entire object and I don't scroll the inside elements, else, if I change offset of child element (Item Templates) I change the single element position "breaking" the layout of the Vertical Layout Group;

I tried to find solutions, but I'm new and apparently nothing works when I apply it.

What am I doing wrong?

Solution

  • If your goal is to make a scrollable list of UI objects here is a gif I made on that process. It runs through the layout and each component and it working.

    Example

    If you want to dynamically add objects to this list at runtime, use the Panel_Content transform and instantiate objects using Instantiate(yourPrefab, Pane_Content.transform, false). Let me know if you run into issues with this example.