How to split the screen with two equal LinearLayouts?_问答_开发者

Wanna to split a screen for my app with two LinearLayouts. What parameters should I use开发者_运维知识库 to make exact splitting in two equal parts - first LinearLayout on the top and the second one is just under it.

Use the layout_weight attribute. The layout will roughly look like this:

<LinearLayout android:orientation="horizontal"
    android:layout_height="fill_parent" 
    android:layout_width="fill_parent">

    <LinearLayout 
        android:layout_weight="1" 
        android:layout_height="fill_parent" 
        android:layout_width="0dp"/>

    <LinearLayout 
        android:layout_weight="1" 
        android:layout_height="fill_parent" 
        android:layout_width="0dp"/>

</LinearLayout>

I am answering this question after 4-5 years but best practices to do this as below

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:tools="http://schemas.android.com/tools"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   tools:context=".MainActivity">

   <LinearLayout
      android:id="@+id/firstLayout"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:layout_toLeftOf="@+id/secondView"
      android:orientation="vertical"></LinearLayout>

   <View
      android:id="@+id/secondView"
      android:layout_width="0dp"
      android:layout_height="match_parent"
      android:layout_centerHorizontal="true" />

   <LinearLayout
      android:id="@+id/thirdLayout"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:layout_toRightOf="@+id/secondView"
      android:orientation="vertical"></LinearLayout>
</RelativeLayout>

This is right approach as use of layout_weight is always heavy for UI operations. Splitting Layout equally using LinearLayout is not good practice

Just putting it out there:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#FF0000"
    android:weightSum="4"
    android:padding="5dp"> <!-- to show what the parent is -->
    <LinearLayout
        android:background="#0000FF"
        android:layout_height="0dp"
        android:layout_width="match_parent"
        android:layout_weight="2" />
    <LinearLayout
        android:background="#00FF00"
        android:layout_height="0dp"
        android:layout_width="match_parent"
        android:layout_weight="1" />
</LinearLayout>

In order to split the ui into two equal parts you can use weightSum of 2 in the parent LinearLayout and assign layout_weight of 1 to each as shown below

<?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="match_parent"
    android:orientation="horizontal"
    android:weightSum="2">

        <LinearLayout
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:orientation="vertical">

        </LinearLayout>

       <LinearLayout
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:orientation="vertical">

       </LinearLayout>


</LinearLayout>

To Split a layout to equal parts

Use Layout Weights. Keep in mind that it is important to set layout_width as 0dp on children to make it work as intended.

on parent layout:

Set weightSum of parent Layout as 1 (android:weightSum="1")

on the child layout:

Set layout_width as 0dp (android:layout_width="0dp")
Set layout_weight as 0.5 [half of weight sum fr equal two] (android:layout_weight="0.5")

To split layout to three equal parts:

parent: weightSum 3
child: layout_weight: 1

To split layout to four equal parts:

parent: weightSum 1
child: layout_weight: 0.25

To split layout to n equal parts:

parent: weightSum n

child: layout_weight: 1

Below is an example layout for splitting layout to two equal parts.

<LinearLayout
    android:id="@+id/layout_top"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:weightSum="1">

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0.5"
        android:orientation="vertical">

        <TextView .. />

        <EditText .../>

    </LinearLayout>

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0.5"
        android:orientation="vertical">

        <TextView ../>

        <EditText ../>

    </LinearLayout>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <LinearLayout
            android:orientation="vertical"
            android:layout_weight="1"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            tools:context=".MainActivity">
            <TextView
                android:layout_marginTop="16dp"
                android:textSize="18sp"
                android:textStyle="bold"
                android:padding="4dp"
                android:textColor="#EA80FC"
                android:fontFamily="sans-serif-medium"
                android:text="@string/team_a"
                android:gravity="center_horizontal"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
            <TextView
                android:id="@+id/team_a_score"
                android:text="@string/_0"
                android:textSize="56sp"
                android:padding="4dp"
                android:gravity="center_horizontal"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
            <TextView
                android:id="@+id/team_a_fouls"
                android:text="@string/fouls"
                android:padding="4dp"
                android:textSize="26sp"
                android:gravity="center_horizontal"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
            <Button
                android:text="@string/_1_points"
                android:layout_width="match_parent"
                android:onClick="addOnePointTeamA"
                android:textColor="#fff"
                android:layout_margin="6dp"
                android:layout_height="wrap_content" />
            <Button
                android:text="@string/_2_points"
                android:textColor="#fff"
                android:onClick="addTwoPointTeamA"
                android:layout_width="match_parent"
                android:layout_margin="6dp"
                android:layout_height="wrap_content" />
            <Button
                android:text="@string/_3_points"
                android:textColor="#fff"
                android:onClick="addThreePointTeamA"
                android:layout_margin="6dp"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
            <Button
                android:text="@string/_1_point_foul"
                android:textColor="#fff"
                android:layout_width="match_parent"
                android:onClick="addOnePointFoulTeamA"
                android:layout_margin="6dp"
                android:layout_height="wrap_content" />
        </LinearLayout>
        <LinearLayout
            android:orientation="vertical"
            android:layout_weight="1"
            android:layout_width="0dp"
            android:layout_height="match_parent"
            tools:context=".MainActivity">
            <TextView
                android:text="@string/team_b"
                android:textColor="#EA80FC"
                android:textStyle="bold"
                android:padding="4dp"
                android:layout_marginTop="16dp"
                android:fontFamily="sans-serif-medium"
                android:textSize="18sp"
                android:gravity="center_horizontal"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
            <TextView
                android:id="@+id/team_b_score"
                android:text="0"
                android:padding="4dp"
                android:textSize="56sp"
                android:gravity="center_horizontal"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
            <TextView
                android:id="@+id/team_b_fouls"
                android:text="Fouls"
                android:padding="4dp"
                android:textSize="26sp"
                android:gravity="center_horizontal"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
            <Button
                android:text="@string/_1_points"
                android:textColor="#fff"
                android:fontFamily="sans-serif-medium"
                android:layout_width="match_parent"
                android:onClick="addOnePointTeamB"
                android:layout_margin="6dp"
                android:layout_height="wrap_content" />
            <Button
                android:text="@string/_2_points"
                android:layout_margin="6dp"
                android:fontFamily="sans-serif-medium"
                android:textColor="#fff"
                android:onClick="addTwoPointTeamB"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
            <Button
                android:text="@string/_3_points"
                android:fontFamily="sans-serif-medium"
                android:textColor="#fff"
                android:onClick="addThreePointTeamB"
                android:layout_margin="6dp"
                android:layout_width="match_parent"
                android:layout_height="wrap_content" />
            <Button
                android:text="@string/_1_point_foul"
                android:textColor="#fff"
                android:onClick="addOnePointFoulTeamB"
                android:layout_width="match_parent"
                android:layout_margin="6dp"
                android:layout_height="wrap_content" />


        </LinearLayout>
    </LinearLayout>
    <Button
        android:text="@string/reset"
        android:layout_marginBottom="25dp"
        android:onClick="resetScore"
        android:textColor="#fff"
        android:fontFamily="sans-serif-medium"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

</RelativeLayout>

Use android:layout_weight and android:weightSum to divide layouts into equal parts. It is important to set layout_width as 0dp on children to make it work as intended.

On parent layout:

Set weightSum of parent Layout as 2 (android:weightSum="2")

On the child layout:

Set layout_width as 0dp (android:layout_width="0dp") Set layout_weight as 1 [half of weight sum] (android:layout_weight="1")

<!-- Parent layout -->
<LinearLayout
    android:id="@+id/layout_parent"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:weightSum="2">
    <!-- Child layout -->
    <LinearLayout
        android:id="@+id/layout_child_1"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:layout_weight="1">
        ...
    </LinearLayout>
    <LinearLayout
        android:id="@+id/layout_child_1"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:layout_weight="1">
        ...
    </LinearLayout>
</LinearLayout>