Fit ImageViews into Android GridLayout

Question

I need to place 4 images into GridLayout. If I define their sizes hard-coded.

e.g.

android:layout_width="150dp"
android:layout_height="200dp"

It works fine. But my question is, if is it possible to do it without defining sizes? Meanwhile I've tried this:

<GridLayout
    android:layout_width="0dp"
    android:layout_height="0dp"
    android:layout_margin="16dp"
    android:columnCount="2"
    android:orientation="horizontal"
    android:useDefaultMargins="true"
    app:layout_constraintTop_toBottomOf="@+id/top_object"
    app:layout_constraintBottom_toTopOf="@+id/bottom_object"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent">

        <ImageView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:src="@drawable/poster_21"
            android:scaleType="centerCrop"/>

        <ImageView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:src="@drawable/poster_22"
            android:scaleType="centerCrop"/>

        <ImageView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:src="@drawable/poster_23"
            android:scaleType="centerCrop"/>

        <ImageView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:src="@drawable/poster_24"
            android:scaleType="centerCrop"/>

  </GridLayout>

But in this case I have left top image occupies the whole Grid Layout and 3 other images have the same size and are located outside the screen.

Answer 1

You can use 0dp width & height for each GridLayout element, i.e. ImageView

And control the width & height using the column & row weights

<?xml version="1.0" encoding="utf-8"?>
<GridLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:grid="http://schemas.android.com/apk/tools"
    android:layout_width="0dp"
    android:layout_height="0dp"
    android:layout_margin="16dp"
    android:useDefaultMargins="true"
    android:layout_constraintTop_toBottomOf="@+id/top_object"
    android:layout_constraintBottom_toTopOf="@+id/bottom_object"
    android:layout_constraintLeft_toLeftOf="parent"
    android:layout_constraintRight_toRightOf="parent"     
    android:columnCount="2">

    <ImageView
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:scaleType="centerCrop"
        android:src="@drawable/poster_21"
        android:layout_columnWeight="1"
        android:layout_rowWeight="1"
        grid:layout_gravity="center" />

    <ImageView
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:scaleType="centerCrop"
        android:src="@drawable/poster_22"
        android:layout_columnWeight="1"
        android:layout_rowWeight="1"
        grid:layout_gravity="center" />

    <ImageView
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:scaleType="centerCrop"
        android:src="@drawable/poster_23"
        android:text="item 0x2"
        android:layout_columnWeight="1"
        android:layout_rowWeight="1"
        grid:layout_gravity="center" />


    <ImageView
        android:layout_width="0dp"
        android:layout_height="0dp"
        android:scaleType="centerCrop"
        android:src="@drawable/poster_24"
        android:text="item 1x0"
        android:layout_columnWeight="1"
        android:layout_rowWeight="1"
        grid:layout_gravity="center" />

</GridLayout>