Drawable资源之ShapeDrawable资源

This is a generic shape defined in XML.

file location:

res/drawable/filename.xml
The filename is used as the resource ID.

compiled resource datatype:

Resource pointer to a   GradientDrawable.

resource reference:

In Java:   R.drawable.filename
In XML:   @[package:]drawable/filename

syntax:

<?xml version="1.0" encoding="utf-8"?>
<shape
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape=["rectangle" | "oval" | "line" | "ring"] >
    <corners
        android:radius="integer"
        android:topLeftRadius="integer"
        android:topRightRadius="integer"
        android:bottomLeftRadius="integer"
        android:bottomRightRadius="integer" />
    <gradient
        android:angle="integer"
        android:centerX="integer"
        android:centerY="integer"
        android:centerColor="integer"
        android:endColor="color"
        android:gradientRadius="integer"
        android:startColor="color"
        android:type=["linear" | "radial" | "sweep"]
        android:useLevel=["true" | "false"] />
    <padding
        android:left="integer"
        android:top="integer"
        android:right="integer"
        android:bottom="integer" />
    <size
        android:width="integer"
        android:height="integer" />
    <solid
        android:color="color" />
    <stroke
        android:width="integer"
        android:color="color"
        android:dashWidth="integer"
        android:dashGap="integer" />
</shape>

 

elements:

<shape>

The shape drawable. This must be the root element.

attributes:

xmlns:android

String.   Required.  Defines the XML namespace, which must be "http://schemas.android.com/apk/res/android".

android:shape

Keyword. Defines the type of shape. Valid values are:

Value	Desciption
"rectangle"	A rectangle that fills the containing View. This is the default shape.
"oval"	An oval shape that fits the dimensions of the containing View.
"line"	A horizontal line that spans the width of the containing View. This shape requires the <stroke> element to define the width of the line.
"ring"	A ring shape.

The following attributes are used only when android:shape="ring":

android:innerRadius

Dimension. The radius for the inner part of the ring (the hole in the middle), as a dimension value or   dimension resource.

android:innerRadiusRatio

Float. The radius for the inner part of the ring, expressed as a ratio of the ring's width. For instance, if   android:innerRadiusRatio="5", then the inner radius equals the ring's width divided by 5. This value is overridden by   android:innerRadius. Default value is 9.

android:thickness

Dimension. The thickness of the ring, as a dimension value or   dimension resource.

android:thicknessRatio

Float. The thickness of the ring, expressed as a ratio of the ring's width. For instance, if android:thicknessRatio="2", then the thickness equals the ring's width divided by 2. This value is overridden by   android:innerRadius. Default value is 3.

android:useLevel

Boolean. "true" if this is used as a   LevelListDrawable. This should normally be "false" or your shape may not appear.

<corners>

Creates rounded corners for the shape. Applies only when the shape is a rectangle.

attributes:

android:radius

Dimension. The radius for all corners, as a dimension value or   dimension resource. This is overridden for each corner by the following attributes.

android:topLeftRadius

Dimension. The radius for the top-left corner, as a dimension value or   dimension resource.

android:topRightRadius

Dimension. The radius for the top-right corner, as a dimension value or   dimension resource.

android:bottomLeftRadius

Dimension. The radius for the bottom-left corner, as a dimension value or   dimension resource.

android:bottomRightRadius

Dimension. The radius for the bottom-right corner, as a dimension value or   dimension resource.

Note: Every corner must (initially) be provided a corner radius greater than 1, or else no corners are rounded. If you want specific corners to not be rounded, a work-around is to use android:radiusto set a default corner radius greater than 1, but then override each and every corner with the values you really want, providing zero ("0dp") where you don't want rounded corners.

<gradient>

Specifies a gradient color for the shape.

attributes:

android:angle

Integer. The angle for the gradient, in degrees. 0 is left to right, 90 is bottom to top. It must be a multiple of 45. Default is 0.

android:centerX

Float. The relative X-position for the center of the gradient (0 - 1.0).

android:centerY

Float. The relative Y-position for the center of the gradient (0 - 1.0).

android:centerColor

Color. Optional color that comes between the start and end colors, as a hexadecimal value or color resource.

android:endColor

Color. The ending color, as a hexadecimal value or   color resource.

android:gradientRadius

Float. The radius for the gradient. Only applied when   android:type="radial".

android:startColor

Color. The starting color, as a hexadecimal value or   color resource.

android:type

Keyword. The type of gradient pattern to apply. Valid values are:

Value	Description
"linear"	A linear gradient. This is the default.
"radial"	A radial gradient. The start color is the center color.
"sweep"	A sweeping line gradient.

android:useLevel

Boolean. "true" if this is used as a   LevelListDrawable.

<padding>

Padding to apply to the containing View element (this pads the position of the View content, not the shape).

attributes:

android:left

Dimension. Left padding, as a dimension value or   dimension resource.

android:top

Dimension. Top padding, as a dimension value or   dimension resource.

android:right

Dimension. Right padding, as a dimension value or   dimension resource.

android:bottom

Dimension. Bottom padding, as a dimension value or   dimension resource.

<size>

The size of the shape.

attributes:

android:height

Dimension. The height of the shape, as a dimension value or   dimension resource.

android:width

Dimension. The width of the shape, as a dimension value or   dimension resource.

Note: The shape scales to the size of the container View proportionate to the dimensions defined here, by default. When you use the shape in an ImageView, you can restrict scaling by setting theandroid:scaleType to "center".

<solid>

A solid color to fill the shape.

attributes:

android:color

Color. The color to apply to the shape, as a hexadecimal value or   color resource.

<stroke>

A stroke line for the shape.

attributes:

android:width

Dimension. The thickness of the line, as a dimension value or   dimension resource.

android:color

Color. The color of the line, as a hexadecimal value or   color resource.

android:dashGap

Dimension. The distance between line dashes, as a dimension value or   dimension resource. Only valid if   android:dashWidth  is set.

android:dashWidth

Dimension. The size of each dash line, as a dimension value or   dimension resource. Only valid if android:dashGap  is set.

example:

XML file saved at   res/drawable/gradient_box.xml:

 

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">
    <gradient
        android:startColor="#FFFF0000"
        android:endColor="#80FF00FF"
        android:angle="45"/>
    <padding android:left="7dp"
        android:top="7dp"
        android:right="7dp"
        android:bottom="7dp" />
    <corners android:radius="8dp" />
</shape>

 

This layout XML applies the shape drawable to a View:

<TextView
    android:background="@drawable/gradient_box"
    android:layout_height="wrap_content"
    android:layout_width="wrap_content" />

 

This application code gets the shape drawable and applies it to a View:

Resources res = getResources();
Drawable shape = res. getDrawable(R.drawable.gradient_box);

TextView tv = (TextView)findViewByID(R.id.textview);
tv.setBackground(shape);