Unable to set layout width, height and weight of inflated view in XML in Android

Question

I am developing an Android app. In my app, I need to inflate list of views dynamically. I added them and working. The problem is with setting the width and height of layout. Now I will demonstrate my problem with a simple project. Actually, my project is much more complicated than this simple project.

I am inflating views to this layout.

           <LinearLayout
                android:orientation="horizontal"
                android:id="@+id/cm_photos_container"
                android:layout_width="match_parent"
                android:layout_height="wrap_content">

            </LinearLayout>

I am looping through a list of bitmap and adding view dynamically as follow

for(Bitmap bmp : bitmaps)
{
     View preview = layoutInflater.inflate(R.layout.item_cm_preview_image,null);
                ImageView previewImageView = (ImageView)preview.findViewById(R.id.item_cm_preview_image);
                previewImageView.setImageBitmap(bmp);
     container.addView(preview);
}

Please note, in the above code, container is a LinearLayout added dynamically to the parent XML in the above.

container = new LinearLayout(this);
                    container.setOrientation(LinearLayout.HORIZONTAL);
                    LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
                    container.setLayoutParams(params);

parentLinearLayout.addView(container);

This is my item_cm_preview_image.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    android:layout_weight="1"
    android:layout_height="400dp"
    android:layout_width="0dp"
    xmlns:android="http://schemas.android.com/apk/res/android">
    <ImageView
        android:scaleType="centerCrop"
        android:id="@+id/item_cm_preview_image"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
</LinearLayout>

As you can see, I set the layout height to 400dp, width 0 and layout_weight to 1 in the XML. So all image height must be same and width must be equal because of layout_weight. But the result is not as expected. You can see screenshot below.

As you can see in the screenshot, both layout_weight and height are not working for all inflated views. But if I add extra ViewGroup dynamically and inflate the view to that layout, it is working. Below is my code

//This happening in for loop
LinearLayout wrapper = new LinearLayout(this);
                wrapper.setLayoutParams(new LinearLayout.LayoutParams(0,500,1));

                View preview = layoutInflater.inflate(R.layout.item_cm_preview_image,null);
                ImageView previewImageView = (ImageView)preview.findViewById(R.id.item_cm_preview_image);
                previewImageView.setImageBitmap(bmp);

                wrapper.addView(preview);
                container.addView(wrapper);

This is the result:

As you can see both layout_weight and height working when I use an extra dynamic linear layout. Why is setting layout weight and height in XML not working? Why second way is working? How can I set weight and height in XML layout file? Is it possible?

Answer 1

If you inflate layout using method

View preview = layoutInflater.inflate(R.layout.item_cm_preview_image,null);

it skip its width and height parameters..., but if you will use:

View preview = layoutInflater.inflate(R.layout.item_cm_preview_image,parent,false);

it should work correct, for example if you inflate view in activity as parent you can provide (ViewGroup) getView():

View preview = layoutInflater.inflate(R.layout.item_cm_preview_image,(ViewGroup) getView(), false);