Android layout weight makes layout width 0

Question

I have a LinearLayout under a LinearLayout (master layout), both vertical orientation. I set the master weight sum to 1 and I add the child layout using code with weight of 0.8 and set the width to 0 and the height to MatchParent. But when I run the app it just doesnt show up, by debugging I could find that the width stays 0. Also, when the master layout orientation set to horizontal, it works fine. Why this happens?

This is the xml for the master layout:

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:weightSum="1.0"
    android:id="@+id/main_layout">
</LinearLayout>

The code:

In MainActivity.cs: (This ones just adds the Ore which is extending LinearLayout)

 protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);
            Xamarin.Essentials.Platform.Init(this, savedInstanceState);
            // Set our view from the "main" layout resource
            
            SetContentView(Resource.Layout.activity_main);
            _activity = this;
            CurrentOre = 0;

            LinearLayout layout = FindViewById<LinearLayout>(Resource.Id.main_layout);
            Ore current = OresHandler.GetAllOres()[CurrentOre];
            layout.AddView(current);
            
            
            
        }

The "child" layout: Ore class (extends LinearLayout):

            
            LayoutParameters = new LinearLayout.LayoutParams(0, LayoutParams.MatchParent, 1F);
            Orientation = Orientation.Vertical;
            WeightSum = 1F;
            SetHorizontalGravity(GravityFlags.Center);

// The name
            TextView title = new TextView(Context);
            title.Text = Name;
            title.LayoutParameters = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MatchParent, 0, 0.08F) ;
            title.TextSize = 24;
            title.TextAlignment = TextAlignment.Center;
            title.SetBackgroundColor(Color.Transparent);
            AddView(title);
            // The image button
            Button = new ImageButton(Context);
            Button.LayoutParameters = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MatchParent, 0,0.5F);
            Button.SetScaleType(ScaleType.FitXy);
            Button.SetBackgroundColor(Color.Transparent);
            Button.SetImageResource(ImgId);
            Button.Click += (sender, e) => Damage(1);
            AddView(Button);
            
            AddView(HealthHandler);

(I only placed relevant pieces of code) As you can see, the child layout (Ore) contains a TextView, ImageButton and another component which I created. But I do not think they matter at any way since the program works on horizontal.

Answer 1

Solved. LinearLayout only arranges the size depending on the orientation, so had to add a wrapping LinearLayout with horizontal orientation to change width size.