Android - 如何在线性布局中使按钮更高？

Question

I have a linear layout inside a relative layout, and I want to make the buttons 'taller' to fit the height of the linear layout.

I tried adding padding, as you can see in the screenshot, the layout is 'taller' but the buttons are not. I tried 'fill_parent', 'match_parent' but it didn't make a difference. How do I make the buttons expand in height?

<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"
android:id="@+id/timerLayout">

<Chronometer
    android:id="@+id/chronometer1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="48dp"
    android:text="@string/chronometer"
    android:textSize="50sp" />

<LinearLayout
    android:id="@+id/buttonLayout"
    android:orientation="horizontal"
    android:paddingLeft="4.0dp"
    android:paddingTop="50.0dp"
    android:paddingRight="4.0dp"
    android:paddingBottom="4.0dp"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true">

    <Button
        android:id="@+id/btnReset"
        android:layout_width="0.0dp"
        android:layout_height="fill_parent"
        android:drawableLeft="@drawable/ic_restore_white_24dp"
        android:drawableStart="@drawable/ic_restore_white_24dp"
        android:text="@string/pause_btn"
        android:layout_weight="1.5" />

    <Button
        android:id="@+id/btnStart"
        android:layout_width="0.0dp"
        android:layout_height="fill_parent"
        android:text="@string/start_btn"
        android:drawableLeft="@android:drawable/ic_media_play"
        android:drawableStart="@android:drawable/ic_media_play"
        android:layout_weight="1.5" />

    <Button
        android:id="@+id/btnSave"
        android:layout_width="0.0dp"
        android:layout_height="fill_parent"
        android:text="@string/save_btn"
        android:drawableLeft="@drawable/ic_save_white_24dp"
        android:drawableStart="@drawable/ic_save_white_24dp"
        android:layout_weight="1.0" />
</LinearLayout>

Answer 1

your linearlayout says height:wrap_content so the child elements will takeup only as much space as specified.

Try giving either minHeight for linearlayout or simply remove linearlayout and in your buttons specifiy "alignparentbottom = true". For left-most button give alignparentStart = true.

Answer 2

Take a look at your xml layout file very closely

 <LinearLayout
    android:id="@+id/buttonLayout"
    android:orientation="horizontal"
    android:paddingLeft="4.0dp"

    android:paddingTop="50.0dp" //this guy 

    android:paddingRight="4.0dp"
    android:paddingBottom="4.0dp"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true">

the android:paddingTop is the space on the top of every child in your LinearLayout so if you remove it the buttons will fit.

Answer 3

The extra space you are seeing is from the padding values in your linear layout, and your buttons are already filling the parent linear layout. But your linear layout has specified the following.

android:layout_height="wrap_content"

If you want to see buttons with a larger height, change the height value for your linear layout to something else like:

android:layout_height="300dp"