通过XML定义控件背景形状颜色

在drawable里面定义xml，在background中引用

<Button
	android:id="@+id/completeBtn"
	android:layout_width="80dp"
	android:layout_height="40dp"
	android:layout_marginTop="32dp"
	android:text="完成"
	android:textColor="@color/white"
	android:textSize="18sp"
	android:background="@drawable/green_radius"/>

 

1. 圆角矩形

<?xml version="1.0" encoding="UTF-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape>
            <solid android:color="#10B703" />

            <!-- 应该是圆角 -->
            <corners android:radius="4dp" />
        </shape>
    </item>
</layer-list>

 

2. 左右边框为半圆的矩形

<?xml version="1.0" encoding="UTF-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape>
            <solid android:color="#10B703" />

            <!-- 应该是控件高度的一半 -->
            <corners android:radius="25dp" />
        </shape>
    </item>
</layer-list>

 

3. 带边框的圆角矩形

<?xml version="1.0" encoding="UTF-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape>
        	<!-- 边框 -->
            <stroke android:color="@color/grey97" android:width="1px"/>

            <!-- 主背景色 -->
            <solid android:color="@color/white" />
            
            <!-- 圆角 -->
            <corners android:radius="4dp" />
        </shape>
    </item>
</layer-list>

 

4. 只有部分边角是圆角、别的是直角的矩形

<?xml version="1.0" encoding="UTF-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape>
            <stroke android:color="@color/grey97" android:width="1px"/>

            <solid android:color="@color/white" />
            
            <!-- 需要圆角的地方设置大于0的数值 -->
            <corners
                android:bottomRightRadius="0dp"
                android:bottomLeftRadius="4dp"
                android:topLeftRadius="4dp"
                android:topRightRadius="0dp"/>
        </shape>
    </item>
</layer-list>

 refer Creating a rectangle shape with only two rounded edges

 

5. 某个边框不显示的矩形

<?xml version="1.0" encoding="UTF-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
	<!-- 不需要的边框标识为边框的width负值 -->
    <item android:left="-1px">
        <shape>
            <stroke android:color="@color/grey97" android:width="1px"/>

            <solid android:color="#F0F0F0" />

            <!-- 圆角控制 -->
            <corners
                android:bottomRightRadius="4dp"
                android:bottomLeftRadius="0dp"
                android:topLeftRadius="0dp"
                android:topRightRadius="4dp"/>

        </shape>
    </item>

</layer-list>

  refer Open-sided Android stroke

 

6. 圆形

<?xml version="1.0" encoding="UTF-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
    	<!-- 由控件定义的地方保证高宽相等 -->
		<shape
            android:shape="oval"
            xmlns:android="http://schemas.android.com/apk/res/android">

            <solid android:color="@color/white" />

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

        </shape>
    </item>
</layer-list>

 

7. 点击变换背景

<?xml version="1.0" encoding="UTF-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
	<!-- 正常无点击的情况 -->
    <item android:state_pressed="false">
        <shape>
        	<!-- 可以添加stroke等其他特征 -->
            <solid android:color="@color/color1" />

            <corners android:radius="25dp" />
        </shape>
    </item>

	<!-- 点击时的情况 -->
    <item android:state_pressed="true">
        <shape>
            <solid android:color="@color/color2" />

            <corners android:radius="25dp" />
        </shape>
    </item>
</selector>

 

8. ProgressBar颜色渐变，在progressDrawable中引用

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
	<!-- 初始背景 -->
    <item android:id="@android:id/background">
        <shape>
            <gradient
                android:startColor="#ff9d9e9d"
                android:endColor="#ff9d9e9d"
                />
        </shape>
    </item>

    <!-- 过程中的渐变 -->
    <item android:id="@android:id/progress">
        <clip>
            <shape>
                <gradient
                    android:startColor="@color/light_orange"
                    android:endColor="@color/main_orange" />
            </shape>
        </clip>
    </item>

</layer-list>

 refer How to Customize a Progress Bar In Android

          Custom Drawable for ProgressBar/ProgressDialog

 

9. 普通的线性渐变

<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape>
            <gradient
                android:angle="0"
                android:startColor="#C8C8C8"
                android:centerColor="#979797"
                android:endColor="#C8C8C8"
                android:type="linear" />
        </shape>
    </item>
</layer-list>