How to tile a background image in Android

最新推荐文章于 2025-09-09 18:11:46 发布

转载最新推荐文章于 2025-09-09 18:11:46 发布 · 870 阅读

文章标签：

#image #android #layout #encoding #file #rest

Android 专栏收录该内容

76 篇文章

订阅专栏

本文将指导您如何在Android应用中使用背景图片实现重复的像素图案，通过创建自定义的BitmapDrawable类实例并引用简单的图片资源，轻松在布局中应用这种效果。为了确保在不同分辨率的设备上都能正常显示，需要为高密度、中密度和低密度屏幕分别准备相应的图片资源文件。

How to tile a background image in Android

For one of the apps I'm working on I wanted to have a nice pixel pattern tiled behind my widgets.
After a little bit of hunting around I found this tutorial, and I thought I'd clean up the lessons within and show you how.

Here's the contents of my main.xml layout file,

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@drawable/backrepeat"
    android:gravity="center_horizontal"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />

</LinearLayout>

which is referenced in code in the standard way like this:


main);

...// (rest of onCreate method continues here..)

Now note this line:

android:background="@drawable/backrepeat"

What's going on there?
.. Glad you asked!

Here's a quick screenshot of the contents of one of my drawable folders in my project:

What is this
backrepeat.xml?

Well, here's the contents of that file here:

<bitmap
 xmlns:android="http://schemas.android.com/apk/res/android"
 android:src="@drawable/scale1"
 android:tileMode="repeat"
 android:dither="true" />

Can you see what's going on?
Backrepeat.xml defines an instance of the BitmapDrawable class, and that class references our simple scale1.jpg, located in the drawable-hdpi folder.

Simply by adding the:

<bitmap
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:src="@drawable/scale1"
    android:tileMode="repeat"
    android:dither="true" />

line in bold, we are able to achieve results such as this:

Easy isn't it?

One thing to keep in mind is that you should have folders drawable-hdpi, drawable-mdpi & drawable-ldpi, you'll need to add this backrepeat.xml file and the relevant images to each of these to allow this functionality in high, medium and low dpi (dots per inch) screen sizes.

Enjoy.