Putting a menu bar on the bottom of the screen while using ExpandableListView

Question

I figured out how to get the menu bar on top of the screen. It stays in position while I move around the main menu I created using expandableListView. However, I would like the menu bar to be on the bottom of the screen instead of the top. I played around with relativeView and got the bar on the bottom, however, the main menu disappears. Here is my main xml file

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


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

    <Button
        android:id="@+id/buttonbefore"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="50"
        android:text="back" />

    <Button
        android:id="@+id/buttonnext"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_weight="50"
        android:text="Next" />
</LinearLayout>

<ExpandableListView
    android:id="@+id/android:list"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" />

<TextView
    android:id="@+id/android:empty"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:text="@string/main_no_items" />

Then I used this for java to get it to appear in my program.

   LinearLayout bottomMenu = (LinearLayout)findViewById(R.id.buttons);

I tried playing around with the gravity and it did nothing. I can add more code from my program if you think it will help.

Answer 1

I'm assuming your buttons LinearLayout is the 'menu bar' you're referring to?

You can actually accomplish what you're looking for using either a RelativeLayout or a LinearLayout.

LinearLayout:

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

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

        <ExpandableListView
            android:id="@android:id/list"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent" />

        <TextView
            android:id="@android:id/empty"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:text="@string/main_no_items" />
    </LinearLayout>

    <LinearLayout
        android:id="@+id/buttons"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:orientation="horizontal" >

        <Button
            android:id="@+id/buttonbefore"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="back" />

        <Button
            android:id="@+id/buttonnext"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="Next" />
    </LinearLayout>

</LinearLayout>

The buttons are bottom-aligned by setting the gravity, while the list is told to take up all other available space by giving it a weight of '1' and setting a height of '0dp'. That will cause it to stretch as much as possible without pushing the buttons off-screen.

RelativeLayout:

<?xml version="1.0" encoding="UTF-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_above="@+id/buttons"
        android:orientation="vertical" >

        <ExpandableListView
            android:id="@android:id/list"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent" />

        <TextView
            android:id="@android:id/empty"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:text="@string/main_no_items" />
    </LinearLayout>

    <LinearLayout
        android:id="@+id/buttons"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:orientation="horizontal" >

        <Button
            android:id="@+id/buttonbefore"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="back" />

        <Button
            android:id="@+id/buttonnext"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="Next" />
    </LinearLayout>

</RelativeLayout>

The buttons are bottom-aligned by setting the alignment on the parent. The list is told to fill all height, but stay 'above' the buttons.

On a general note: in order for this to work, I'm pretty sure that the list and empty views need to be combined together in their own layout.

Answer 2

The way to align the buttons to the bottom is to change your top level LinearLayout into a RelativeLayout. Then you can add the attribute android:layout_alignParentBottom="true" to your LinearLayout @+id/buttons, which holds your two buttons.