blocks|key|1022902|text|您可以简单地在可绘制对象上启用抖动。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1022903|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

You can simply enable dithering on your Drawable object.

blocks|key|1022943|text|就像Romain+Guy建议的那样：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1022944|listView.getBackground().setDither(true);|code-block|syntax|javascript|1022945|解决了我的问题|1022946|如果这还不够，特别是对于AMOLED和/或hdpi设备，请尝试执行以下操作：|1022947|@Override
public+void+onAttachedToWindow()+{
++++super.onAttachedToWindow();
++++Window+window+=+getWindow();
++++window.setFormat(PixelFormat.RGBA_8888);
}|1022948|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|D|7|S|8|@]|9|@]|A|$E|F]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

As Romain Guy suggests:

<pre><code>listView.getBackground().setDither(true);
</code></pre>

solves my problem

If this is not enough especially for AMOLED and/or hdpi devices try this:

<pre><code>@Override
public void onAttachedToWindow() {
 super.onAttachedToWindow();
 Window window = getWindow();
 window.setFormat(PixelFormat.RGBA_8888);
}
</code></pre>

blocks|key|1237701|text|把这个放到你的活动中：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1237702|@Override
public+void+onAttachedToWindow()+{
++++super.onAttachedToWindow();
++++Window+window+=+getWindow();
++++window.setFormat(PixelFormat.RGBA_8888);
}|code-block|syntax|javascript|1237703|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Put this in your Activity:

<pre><code>@Override
public void onAttachedToWindow() {
 super.onAttachedToWindow();
 Window window = getWindow();
 window.setFormat(PixelFormat.RGBA_8888);
}
</code></pre>

blocks|key|1237756|text|对我来说，HTC+Desire是这样工作的|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1237757|window.getDecorView().getBackground().setDither(true);|code-block|syntax|javascript|1237758|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

For me on HTC Desire works like this

<pre><code>window.getDecorView().getBackground().setDither(true);
</code></pre>

blocks|key|1237864|text|对我来说，当我在渐变上设置android:useLevel=为“真”时，条带消失了:+gradient_dark.xml|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1237865|<?xml+version="1.0"+encoding="utf-8"?>
<shape+xmlns:android="http://schemas.android.com/apk/res/android"
++++android:shape="rectangle">
++++<gradient+android:startColor="#464646"
++++++++android:endColor="#323232"
++++++++android:angle="270"
++++++++android:type="linear"
++++++++android:useLevel="true"
+++++++++/>
</shape>|code-block|syntax|javascript|1237866|但是首先我尝试使用一个带有"noise“的图层列表来删除条带，这很有帮助，但仍然有一些条带。|1237867|<?xml+version="1.0"+encoding="utf-8"?>
<layer-list+xmlns:android="http://schemas.android.com/apk/res/android"+>
++++<item+android:drawable="@drawable/gradient_dark"/>
++++<item>
++++++++<bitmap
++++++++++++android:gravity="center"
++++++++++++android:src="@drawable/noise_repeater"
++++++++++++android:tileMode="repeat"+/>
++++</item>

</layer-list>|1237868|我创建并使用的"noise_repeater“可绘制文件|1237869|​|1237870|📷|atomic|offset|length|1237871|1237872|entityMap|0|IMAGE|mutability|IMMUTABLE|imageUrl|https://ask.qcloudimg.com/http-save/yehe-900000/cbb2c3347b78524c46944a38234ee734.png|imageAlt^0|0|0|0|0|0|0|0|1|0|0|0^^$0|@$1|2|3|4|5|6|7|13|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|14|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|15|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|16|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|17|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|18|8|@]|9|@]|A|$]]|$1|O|3|P|5|Q|7|19|8|@]|9|@$R|1A|S|1B|1|1C]]|A|$]]|$1|T|3|N|5|6|7|1D|8|@]|9|@]|A|$]]|$1|U|3|-4|5|6|7|1E|8|@]|9|@]|A|$]]]|V|$W|$5|X|Y|Z|A|$10|11|12|-4]]]]

For me the banding disappeared when I set the android:useLevel="true" on the gradient:
gradient_dark.xml

<pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
&lt;shape xmlns:android="http://schemas.android.com/apk/res/android"
 android:shape="rectangle"&gt;
 &lt;gradient android:startColor="#464646"
 android:endColor="#323232"
 android:angle="270"
 android:type="linear"
 android:useLevel="true"
 /&gt;
&lt;/shape&gt;
</code></pre>

But first I tried using a Layer-List with a "noise" drawable to remove the banding, it helps but there is still some banding.

<pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
&lt;layer-list xmlns:android="http://schemas.android.com/apk/res/android" &gt;
 &lt;item android:drawable="@drawable/gradient_dark"/&gt;
 &lt;item&gt;
 &lt;bitmap
 android:gravity="center"
 android:src="@drawable/noise_repeater"
 android:tileMode="repeat" /&gt;
 &lt;/item&gt;

&lt;/layer-list&gt;
</code></pre>

The "noise_repeater" drawable i created and used

<img src="https://i.stack.imgur.com/gAKOv.png" alt="enter image description here">

blocks|key|1023197|text|唯一对我起作用的是在startColor和endColor上都设置了一个略微透明的alpha通道。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1023198|<?xml+version="1.0"+encoding="utf-8"?>
<shape+xmlns:android="http://schemas.android.com/apk/res/android">
++++<gradient+
++++++++android:startColor="#FE3A3C39"+
++++++++android:endColor="#FE181818"
++++++++android:angle="270"
+++++/>
</shape>|code-block|syntax|javascript|1023199|我是从另一个SO问题中得到这个想法的：android:dither=“true”+does+not+dither,+what's+wrong?|offset|length|1023200|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/4769885/androiddither-true-does-not-dither-whats-wrong^0|0|0|J|1G|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

The only thing that worked for me was to set a slightly-transparent alpha channel on both the startColor and endColor.

<pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
&lt;shape xmlns:android="http://schemas.android.com/apk/res/android"&gt;
 &lt;gradient 
 android:startColor="#FE3A3C39" 
 android:endColor="#FE181818"
 android:angle="270"
 /&gt;
&lt;/shape&gt;
</code></pre>

I got the idea to try this from this other SO question: <a href="https://stackoverflow.com/questions/4769885/androiddither-true-does-not-dither-whats-wrong">android:dither=“true” does not dither, what's wrong?</a>

blocks|key|1237984|text|如果抖动和RGBA_888设置在某些手机上没有帮助，解决方案可以是将元素layerType设置为software，以禁用硬件加速|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1237985|android:layerType="software"|code-block|syntax|javascript|1237986|这解决了我在三星S5手机上的问题。|1237987|entityMap^0|10|9|1C|8|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|V|8|@]|D|@]|E|$]]]|N|$]]

If the dither and RGBA_888 setting don't help on some phones, the solution can be to set the element <code>layerType</code> to <code>software</code>, to disable the hardware acceleration

<pre><code>android:layerType="software"
</code></pre>

This fixed my problem on a Samsung S5 phone.

I'm trying to apply a linear gradient to my ListView.
This is the content of my drawable xml:

<pre><code> &lt;?xml version="1.0" encoding="utf-8"?&gt;
&lt;shape xmlns:android="http://schemas.android.com/apk/res/android"&gt;
 &lt;gradient 
 android:startColor="#3A3C39" 
 android:endColor="#181818"
 android:angle="270"
 /&gt;
 &lt;corners android:radius="0dp" /&gt;
&lt;/shape&gt;
</code></pre>

So I apply it to my ListView with:

<pre><code>android:background="@drawable/shape_background_grey"
</code></pre>

It works but it looks very "banded" on emulator and on a real device too.

Is there any way to reduce this "behaviour"?

Android: Using linear gradient as background looks banded

我正在尝试将线性渐变应用于我的ListView。这是我的可绘制xml的内容： <?xml version="1.0" encoding="utf-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android"> <gradient ...

问Android:使用线性渐变作为背景看起来有条带
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