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shape標簽能定義多少種類型的Drawable？
shape 可以定義四種類型的幾何圖形，由 android:shape 屬性指定
line --> 線
rectangle --> 矩形（圓角矩形）
oval --> 橢圓，圓
ring --> 圓環
矩形（邊框+填充）
image.png
矩形實線邊框內部無填充：rect_solid_border.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 實線邊框 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<stroke
android:width="2dp"
android:color="#ffff0000" />
</shape>
矩形虛線邊框內部無填充：rect_dashed_border.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 虛線邊框 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<stroke
android:width="2dp"
android:color="#ffff0000"
android:dashGap="5dp"
android:dashWidth="10dp" />
</shape>
矩形實線邊框-內部填充：rect_solid_border_and_fill.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 實線邊框+內部填充 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<stroke
android:width="2dp"
android:color="#ffff0000" />
<solid android:color="#ff00ffff" />
</shape>
矩形虛線邊框-內部填充：rect_dashed_border_and_fill.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 虛線邊框+內部填充 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<stroke
android:width="2dp"
android:color="#ffff0000"
android:dashGap="5dp"
android:dashWidth="10dp" />
<solid android:color="#ff00ffff" />
</shape>
圓角矩形
image.png
圓角矩形-只有邊框：rect_rounded_border.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形邊框圓角 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size android:height="100dp"
android:width="100dp"/>
<stroke
android:width="2dp"
android:color="#ffff0000" />
<corners android:bottomLeftRadius="2dp"
android:bottomRightRadius="2dp"
android:topLeftRadius="2dp"
android:topRightRadius="2dp" />
</shape>
圓角矩形-只有內部填充：rect_rounded_fill.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 圓角矩形 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size android:height="100dp"
android:width="100dp"/>
<solid android:color="#8000ff00" />
<corners android:bottomLeftRadius="2dp"
android:bottomRightRadius="2dp"
android:topLeftRadius="2dp"
android:topRightRadius="2dp" />
</shape>
圓角矩形-有邊框有填充:rect_rounded_border_and_fill.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形邊框+填充 圓角 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size android:height="100dp"
android:width="100dp"/>
<stroke
android:width="2dp"
android:color="#ffff0000" />
<solid android:color="#8000ff00" />
<corners android:bottomLeftRadius="2dp"
android:bottomRightRadius="2dp"
android:topLeftRadius="2dp"
android:topRightRadius="2dp" />
</shape>
圓角矩形-左邊圓角為一個半圓弧：rect_rounded_left_arc.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形圓角+左右兩邊為一個圓弧 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size
android:width="50dp"
android:height="10dp" />
<solid android:color="#8000ff00" />
<!-- 圓角半徑是高度的一般就是一個圓弧了 -->
<corners
android:bottomLeftRadius="20dp"
android:topLeftRadius="20dp" />
</shape>
圓角矩形-左右兩邊都是半圓弧:rect_rounded_left_right_arc.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形圓角+左右兩邊為一個圓弧 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size
android:width="50dp"
android:height="10dp" />
<solid android:color="#8000ff00" />
<!-- 圓角半徑是高度的一般就是一個圓弧了 -->
<corners android:radius="20dp" />
</shape>
圓角矩形-左右兩邊都是半圓弧-帶邊框：rect_rounded_left_right_arc_border.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形圓角+左右兩邊為一個圓弧 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size
android:width="50dp"
android:height="10dp" />
<stroke android:color="#ffff0000"
android:width="2dp"/>
<solid android:color="#8000ff00" />
<!-- 圓角半徑是高度的一般就是一個圓弧了 -->
<corners android:radius="20dp" />
</shape>
圓角矩形-圓：rect_rounded_arc.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形圓角+圓出一個圓弧 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size android:height="10dp"
android:width="10dp"/>
<solid android:color="#8000ff00" />
<corners android:radius="20dp" />
</shape>
圓角矩形-上下兩邊半圓弧:rect_rounded_top_bottom_arc.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形圓角+左右兩邊為一個圓弧 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size
android:width="10dp"
android:height="60dp" />
<solid android:color="#8000ff00" />
<!-- 圓角半徑是高度的一般就是一個圓弧了 -->
<corners android:radius="10dp" />
</shape>
漸變效果（以矩形為例）
image.png
垂直線性漸變：rect_gradient_linear_vertical.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形內部填充-線性垂直漸變 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size
android:width="@dimen/shape_size"
android:height="@dimen/shape_size" />
<stroke
android:width="1px"
android:color="#ffff00ff" />
<!-- 調整angle實現水平漸變，垂直漸變或者對角漸變 -->
<gradient
android:angle="-45"
android:centerX="0.5"
android:centerY="0.4"
android:centerColor="#8000ff00"
android:endColor="#1000ff00"
android:startColor="#ff00ff00"
android:type="linear" />
</shape>
水平線性漸變:rect_gradient_linear_horizon.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形內部填充-線性水平漸變 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size
android:width="@dimen/shape_size"
android:height="@dimen/shape_size" />
<stroke
android:width="1px"
android:color="#ffff00ff" />
<!-- 調整angle實現水平漸變，垂直漸變或者對角漸變 -->
<gradient
android:angle="0"
android:centerX="0.5"
android:centerY="0.5"
android:centerColor="#8000ff00"
android:endColor="#ff00ff00"
android:startColor="#1000ff00"
android:type="linear" />
</shape>
對角線線性漸變：rect_gradient_linear_diagonal.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形內部填充-線性對角線漸變 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size
android:width="@dimen/shape_size"
android:height="@dimen/shape_size" />
<stroke
android:width="1px"
android:color="#ffff00ff" />
<!-- 調整angle實現水平漸變，垂直漸變或者對角漸變 -->
<gradient
android:angle="45"
android:centerX="0.5"
android:centerY="0.5"
android:centerColor="#8000ff00"
android:endColor="#1000ff00"
android:startColor="#ff00ff00"
android:type="linear" />
</shape>
徑向漸變：rect_gradient_radial.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形內部填充-徑向漸變,一般不用在rect上，用到圓或者橢圓上 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<size
android:width="@dimen/shape_size"
android:height="@dimen/shape_size" />
<stroke
android:width="1px"
android:color="#ffff00ff" />
<!-- 徑向漸變angle無效 -->
<gradient
android:angle="0"
android:centerX="0.5"
android:centerY="0.5"
android:startColor="#0000ff00"
android:endColor="#ff00ff00"
android:gradientRadius="40dp"
android:type="radial" />
</shape>
掃描漸變：rect_gradient_sweep.xml
<?xml version="1.0" encoding="utf-8"?>
<!-- 矩形內部填充-掃描漸變 -->
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:useLevel="true">
<!--如果布局中沒有設置View的大小，會size設置的大小為默認值-->
<size
android:width="20dp"
android:height="20dp" />
<stroke
android:width="1px"
android:color="#ffff00ff" />
<!--調整angle不能實現角度變化
centerX,centerY是中心點的位置，這里用的是百分比值（0-1）
在rect中gradientRadius無效-->
<gradient
android:angle="0"
android:centerX="0.5"
android:centerY="0.5"
android:startColor="#ff00ff00"
android:gradientRadius="20dp"
android:type="sweep" />
</shape>
