Android 布局：宽度为父级的一半

Question

I have a very simple layout that I can't make it looks like I want. It's a LinearLayout with a button and a Switch. I want them to show one above the other, but I want their width to be the half of the parent layout.

|--LinearLayout---------|
|                       |
| -----------           |
||   Switch  |          |
| -----------           |
| -----------           |
||   button  |          |
| -----------           |
 ------------------------

I've been looking at other similar answer in SO but I couldn't find a solution that works for me. This is what I've tried so far:

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="vertical"
                android:weightSum="2" >

                <Switch
                    android:id="@+id/remember_me_switch"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:hint="@string/remember" />

                <Button
                    android:id="@+id/share_button"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:layout_weight="1"
                    android:onClick="loginOnclick"
                    android:text="@string/login_button_text" />

            </LinearLayout>

With this, the button and the switch take all the space of the parent instead of take only the half. I've tried with android:layout_width = 0dp in the children but it makes they disappear.

Any help, please?

Answer 1

One possible way is to have a master horizontal LinearLayout that splits the width to 2, and inside it have the vertical layout

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

            <Switch
                android:id="@+id/remember_me_switch"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:hint="@string/remember" />

            <Button
                android:id="@+id/share_button"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:onClick="loginOnclick"
                android:text="@string/login_button_text" />

        </LinearLayout>
        <!-- Right side spacer -->
        <View
           android:layout_width="0dp"
           android:layout_height="1dp"
           android:layout_weight="1" />

    </LinearLayout>

Answer 2

The trick is to use 0dp for the size you want manage via layout_weight ! Try this

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:weightSum="2" >

        <LinearLayout
            android:layout_width="0dp"
            android:layout_height="match_parent"
            android:orientation="vertical"
            android:layout_weight="1"
            android:weightSum="2" >

            <Switch
                android:id="@+id/remember_me_switch"
                android:layout_width="match_parent"
                android:layout_height="0dp"
                android:layout_weight="1"
                android:hint="@string/remember" />

            <Button
                android:id="@+id/share_button"
                android:layout_width="match_parent"
                android:layout_height="0dp"
                android:layout_weight="1"
                android:onClick="loginOnclick"
                android:text="@string/login_button_text" />

        </LinearLayout>

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

    </LinearLayout>

Answer 3

Try this code

<LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical"
            android:weightSum="2" >

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

                <Switch
                    android:id="@+id/remember_me_switch"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"
                    android:hint="@string/remember" />

               <View 
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"/>
            </LinearLayout>

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

                <Button
                    android:id="@+id/share_button"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent"
                    android:layout_weight="1"
                    android:onClick="loginOnclick"
                    android:text="@string/login_button_text" />

               <View 
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:layout_weight="1"/>
             </LinearLayout>
        </LinearLayout>

Answer 4

Button button = (Button) findViewById(R.id.share_button);
DisplayMetrics displaymetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
int width = displaymetrics.widthPixels;
int buttonWidth = width/2;

set this buttonWidth to your button like button.setWidth(buttonWidth);

Answer 5

int params = linearLayout.getWidth()/2;

ViewGroup.LayoutParams( params, ViewGroup.LayoutParams.WRAP_CONTENT));

Answer 6

Short answer:

1. Use android:weightSum="2" in your horizontal parent layout
2. Use android:layout_weight="1" and android:layout_width="0dp" in your children layouts.