Evenly distribute elements on screen

Question

I want to evenly distribute the elements "checkbox, desayuno,elegir hora" to the full width of the screen.After the "elegir hora" button there is a small Textview where the chosen time is shown, but very small. I have tried setting android:layout_weight="1" but it didn't work.this is how it is displayed:screenshot

Heres the layout code:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="vertical">
    <TextView
        android:id="@+id/nombre"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Nombre de la pastilla"
        android:gravity="center|center"
        />
    <EditText
        android:id="@+id/nombrePastilla"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="textPersonName"
        android:text=""
        android:background="@color/color_blanco"
        />
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

    <CheckBox
        android:id="@+id/checkBoxDesayuno"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:text="Desayuno"
        android:layout_weight="1"
        />

    <Button
        android:id="@+id/buttonDesayuno"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:text="Elegir hora"
        android:layout_weight="1"
        />

        <TextView
            android:id="@+id/horaDesayuno"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text=""
            android:layout_weight="1"
            />

    </LinearLayout>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal">
        <CheckBox
            android:id="@+id/checkBoxComida"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text="Comida"

            />

        <Button
            android:id="@+id/buttonComida"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text="Elegir hora" />
        <TextView
            android:id="@+id/horaComida"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text=""

            />
    </LinearLayout>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal">
        <CheckBox
            android:id="@+id/checkBoxCena"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text="Cena" />

        <Button
            android:id="@+id/buttonCena"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text="Elegir hora" />
        <TextView
            android:id="@+id/horaCena"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:text=""

            />
    </LinearLayout>
    <Button
        android:id="@+id/finalizar"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="Finalizar" />
</LinearLayout>

Answer 1

//You have to give weightsum to linear layout and layoutweight to your textview 
and checkbox(Simply copy and paste this)

<?xml version="1.0" encoding="utf-8"?>
  <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="match_parent"
   android:layout_height="wrap_content"
   android:orientation="vertical">

<TextView
    android:id="@+id/nombre"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:gravity="center|center"
    android:text="Nombre de la pastilla" />

<EditText
    android:id="@+id/nombrePastilla"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/black"
    android:ems="10"
    android:inputType="textPersonName"
    android:text="" />

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:weightSum="1">

    <CheckBox
        android:id="@+id/checkBoxDesayuno"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="0.3"
        android:text="Desayuno" />

    <Button
        android:id="@+id/buttonDesayuno"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="0.4"
        android:text="Elegir hora" />

    <TextView
        android:id="@+id/horaDesayuno"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="0.3"
        android:gravity="start|center_vertical"
        android:text="dmeo"
        android:textSize="18dp" />

</LinearLayout>

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:weightSum="1">

    <CheckBox
        android:id="@+id/checkBoxComida"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="0.3"
        android:text="Comida"

        />

    <Button
        android:id="@+id/buttonComida"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="0.4"
        android:text="Elegir hora" />

    <TextView
        android:id="@+id/horaComida"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="0.3"
        android:gravity="start|center_vertical"
        android:text="dmeo"
        android:textSize="18dp"

        />
</LinearLayout>

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:weightSum="1">

    <CheckBox
        android:id="@+id/checkBoxCena"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="0.3"
        android:text="Cena" />

    <Button
        android:id="@+id/buttonCena"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="0.4"
        android:text="Elegir hora" />

    <TextView
        android:id="@+id/horaCena"
        android:layout_width="0dp"
        android:layout_height="match_parent"
        android:layout_weight="0.3"
        android:gravity="start|center_vertical"
        android:text="dmeo"
        android:textSize="18dp"

        />
</LinearLayout>

<Button
    android:id="@+id/finalizar"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Finalizar" />