I need to create a gradient that is 230dp high (i.e., not the whole screen), with the rest of the screen a solid color. I can't figure out how to do this -- everything I try ends up with the gradient expanding to fill the whole screen. My current XML looks like this:
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android" >
<item android:top="230dp">
<shape android:shape="rectangle" >
<color android:color="#333333" />
</shape>
</item>
<item>
<shape android:shape="rectangle" >
<gradient
android:angle="270"
android:endColor="#333333"
android:startColor="#D9D9D9"
android:type="linear" />
<size android:height="230dp" />
</shape>
</item>
</layer-list>
I then apply that drawable as the background to my LinearLayout in XML:
<?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:background="#333333" >
<LinearLayout
android:id="@+id/container"
android:orientation="vertical"
android:layout_height="fill_parent"
android:layout_width="fill_parent"
android:background="@drawable/grey_gradient_bg" >
<!-- a bunch of content, buttons, etc. -->
</LinearLayout>
</LinearLayout>
But the gradient expands to fill the whole screen.
I have tried using a PNG for the background, but I get the banding problems described here, and the fixes haven't helped me yet.
- Use a RelativeLayout instead of a LinearLayout
- Instead of using your gradient as a background of the main container of the layout, add a child View, set the height explicitly to the size you want (230dp), and set the background of that view to your gradient.
Something like this might help you :)
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/container"
android:layout_width="fill_parent"
android:layout_height="320dip"
android:orientation="vertical"
android:background="@drawable/grey_gradient_bg">
</LinearLayout>
The problem you encountered was because your layout had fill_parent
on height.
Hope this will help you.
Good luck, Arkde
If your project doesn't require API < 21 you may set the size of your gradient directly in your drawable, like that:
<item android:height="230dp">
<shape android:shape="rectangle" >
<gradient
android:angle="270"
android:endColor="#333333"
android:startColor="#D9D9D9"
android:type="linear" />
</shape>
</item>
Anyway, to support API < 21 without this behavior, you may add this drawable and then, another drawable with the same name in the drawable-v21, but it without android:height="230dp".
Setting height in gradient tag or size really doesn't work.
Here's my solution using the other answers:
<?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"
android:background="#333333" >
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="230dp"
android:background="@drawable/grey_gradient_bg"
android:layout_alignParentTop="true" />
<LinearLayout
android:id="@+id/container"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
android:layout_alignParentTop="true" >
<!-- all the content -->
</RelativeLayout>
</RelativeLayout>
grey_gradient_bg is now simple:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle" >
<gradient
android:angle="270"
android:endColor="#333333"
android:startColor="#D9D9D9"
android:type="linear" />
</shape>
来源:https://stackoverflow.com/questions/9687651/gradient-background-that-doesnt-scale