带有背景图像和渐变的 Android 选择器 [英] Android selector with background image and gradient

问题描述

我知道有类似的帖子，但我无法在其中任何一个中找到我的答案.所以，我有这个可绘制的 XML:

I know there are similar post to this but I couldn't find my answer in any of them. So, I have this drawable XML:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_enabled="true">
    <bitmap
        android:src="@drawable/bm_btn_background"
        android:tileMode="repeat"
        android:gravity="center" />
</item>
<item android:state_enabled="true">
    <shape android:shape="rectangle">
        <gradient
            android:startColor="#a0e0b071"
            android:endColor="#a0a67637"
            android:angle="270" />
        <stroke
            android:width="1dp"
            android:color="#5c3708" />
        <corners
            android:radius="5dp" />
        <padding
            android:left="10dp"
            android:top="10dp"
            android:right="10dp"
            android:bottom="10dp" />
    </shape>
</item>
<item android:state_pressed="true" >
    <shape>
        <gradient
            android:startColor="#a0a67637"
            android:endColor="#a0e0b071"
            android:angle="270" />
        <stroke
            android:width="1dp"
            android:color="#5c3708" />
        <corners
            android:radius="5dp" />
        <padding
            android:left="10dp"
            android:top="10dp"
            android:right="10dp"
            android:bottom="10dp" />
    </shape>
</item>

我正在尝试创建一个以重复图像为背景并应用渐变的按钮.使用此代码，我只能看到背景图像，而不是渐变、边框和圆角.此外，当我单击按钮时，它不会改变(渐变应该会改变).不知道这段代码有什么问题?如果我使用图层列表而不是选择器，我会得到所需的结果，但是当我按下按钮时它也不会改变.感谢您的帮助！

I am trying to create a button with a repeated image as background and a gradient applied to it. With this code I only see the background image, not the gradient nor the border and the rounded corners. Also, when I click the button, it doesn't change (the gradient is supposed to change). I don't know what is wrong with this code? If instead of a selector I use a layer-list, I get the desired result but it doesn't change either when I press the button. Thanks for your help!

推荐答案

你的选择器代码是错误的，因为:

Your code for the selector is wrong because:

• You have two elements for the same state and as the selector encounters the first state(state_enabled) for the Bitmap element it will stop there and your gradient永远不会出现(为此你应该使用一个 layer-list ，它具有 Bitmap 和顶部的渐变项)

• You have two elements for the same state and as the selector encounters the first state(state_enabled) for the Bitmap element it will stop there and your gradient will never appear(for this you should use a layer-list that has as items the Bitmap and the gradient on top)

选择器将按顺序匹配状态.当您按下 Button 时，state_pressed 将永远不会被激活，因为选择器将首先匹配第一个元素上的 state_enabled(为此，您应该将 state_pressed 的代码移到 state_enabled 元素上方).

The selector will match states in order. As you press the Button the state_pressed will never be activated because the selector will match first the state_enabled that is on the first element(for this you should move the code for the state_pressed above the state_enabled elements).

事实上，您应该删除state_enabled 并让Bitmap + gradient 成为Button.Bellow 是您的选择器(我假设您只想更改图像上的渐变(但即使在按下状态下图像也应该出现，如果这不是想要的行为，则只留下 state_pressed 的渐变))):

In fact you should just remove the state_enabled and let the Bitmap + gradient be the default value for the Button. Bellow is your selector(I assumed you only want to change gradient on the image(but the image should appear even in the pressed state, if this isn't the wanted behavior leave only the gradient for the state_pressed)):

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:state_pressed="true">
        <layer-list>
            <item>
                <bitmap android:gravity="center" android:src="@drawable/bm_btn_background" android:tileMode="repeat" />
            </item>
            <item>
                <shape>
                     <gradient android:angle="270" android:endColor="#a0e0b071" android:startColor="#a0a67637" />
                     <stroke android:width="1dp" android:color="#5c3708" />
                     <corners android:radius="5dp" />
                     <padding android:bottom="10dp" android:left="10dp" android:right="10dp" android:top="10dp" />
                </shape>
            </item>
        </layer-list>
    </item>

    <item android:state_enabled="true">
        <layer-list>
            <item>
                <bitmap android:gravity="center" android:src="@drawable/bm_btn_background" android:tileMode="repeat" />
            </item>
            <item>
                <shape android:shape="rectangle">
                    <gradient android:angle="270" android:endColor="#a0a67637" android:startColor="#a0e0b071" />
                    <stroke android:width="1dp" android:color="#5c3708" />
                    <corners android:radius="5dp" />
                    <padding android:bottom="10dp" android:left="10dp" android:right="10dp" android:top="10dp" />
                </shape>
            </item>
        </layer-list>
    </item>


</selector>

这篇关于带有背景图像和渐变的 Android 选择器的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！