Android-LinearLayout背景为“上方”视图

Question

I am trying to apply a simple gradient background to my main LinearLayout. My problem is that the background refuses to stay in the background and instead decides to also cover my views (TextViews and Buttons, in this case). What am I doing wrong/am I missing? Thanks for your help!

main layout:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/mainLinearLayout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@drawable/bg_gradient"
android:orientation="vertical" 
>

<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Select the PC to communicate with..." />

<TextView
    android:id="@+id/textViewStatus"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Status" />

<RadioGroup
    android:id="@+id/radioGroupDevices"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" >

</RadioGroup>  

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

    <Button
        android:id="@+id/btnBack"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="&lt;&lt;" />

    <Button
        android:id="@+id/btnVolDown"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="-" />

    <Button
        android:id="@+id/btnPlayPause"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="|>" />

    <Button
        android:id="@+id/btnVolUp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="+" />

    <Button
        android:id="@+id/btnNext"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text=">>" />

   </LinearLayout>

</LinearLayout>

drawable/bg_gradient.xml:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <gradient android:angle="270" android:endColor="#181818" android:startColor="#616161"/>

    <stroke android:width="1dp" android:color="#343434" />
</shape>

Result (Screenshot from Eclipse xml editor, but looks the same on the actual phone) http://s14.directupload.net/images/130415/q8q6hcmn.png

As you can see, the text lines and the buttons appear to be at least partially covered by the background. I also tried to use a normal black background, but with the same result. All views appear "foggy" behind a black haze.

Answer 1

It seems you are developing for the android version 3 or higher...so in this versions and the versions above the theme is set such as the controls seems to be having transparent background...

try changing the controls(buttons,textviews) background to some hash color values

eg:- android:background="#ffaaff"

now you need not to change your code...give it a try as it is...

for your buttons put this in your code to make them transparent...

v.setBackgroundColor(0x0000FF00 );

hope this works for you

Answer 2

I do not see your buttons to be polluted by your gradient. As for the top most text - it's normal as by default TextView background is transparent, so container's bg will be seen thru it.