AttrHelper

java.lang.Object
- ohos.agp.components.AttrHelper

```
public class AttrHelper
extends Object
```
Converts the type of attribute values from character string to integer or Boolean.

从以下版本开始:

3

构造器概要

构造器
构造器说明

AttrHelper()
Default constructor used to create a AttrHelper instance.

构造器
构造器	说明
`AttrHelper()`	Default constructor used to create a `AttrHelper` instance.

方法概要

所有方法静态方法具体方法
限定符和类型	方法	说明
`static int`	`convertDimensionToPix(String value, float density, int defaultValue)`	Converts a dimension value to a number of pixels.
`static int`	`convertDimensionToPix(Context context, String value, int defaultValue)`	Converts a dimension value into a pixel value.
`static BlendMode`	`convertValueToBlendMode(String value, BlendMode defaultValue)`	Converts a value from a character string to an integer.
`static boolean`	`convertValueToBoolean(String value, boolean defaultValue)`	Converts a value from a character string to a Boolean value.
`static Color`	`convertValueToColor(String value)`	Converts a string into a `Color` object.
`static ColorMatrix`	`convertValueToColorMatrix(int value)`	Converts a value from an int to a `ColorMatrix` object.
`static Element`	`convertValueToElement(String value)`	Converts a string into a `Element` object.
`static float`	`convertValueToFloat(String value, float defaultValue)`	Converts a character string to a floating point value.
`static int`	`convertValueToInt(String value, int defaultValue)`	Converts a value from a character string to an integer.
`static long`	`convertValueToLong(String value, long defaultValue)`	Converts a string to a long value.
`static int`	`fp2px(float value, float density)`	Converts a font-size pixel (fp) to a pixel value based on the screen density.
`static int`	`fp2px(float value, float density, float fontRatio)`	Converts a font-size pixel (fp) value to a pixel value based on the screen density and font ratio.
`static int`	`fp2px(float value, Context context)`	Converts a font-size pixel (fp) to a pixel value based on the screen context.
`static float`	`getDensity(Context context)`	Obtains the display density.
`static float`	`getFontRatio(Context context)`	Obtains the font ratio.
`static float`	`px2fp(int value, Context context)`	Converts a pixel to a font-size pixel based on the screen context.
`static float`	`px2vp(int value, Context context)`	Converts a pixel to a virtual pixel based on the screen context.
`static int`	`vp2px(float value, float density)`	Converts a virtual pixel (vp) to a pixel value based on the screen density.
`static int`	`vp2px(float value, Context context)`	Converts a virtual pixel (vp) to a pixel value based on the screen context.

从类继承的方法 java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- 构造器详细资料
  - AttrHelper
```
public AttrHelper()
```
    Default constructor used to create a AttrHelper instance.
- 方法详细资料
  - getDensity
```
public static float getDensity(Context context)
```
    Obtains the display density.
    
    参数:
    
    context - Indicates the application context.
    
    返回:
    
    Returns the display density.
    
    从以下版本开始:
    
    3
  - getFontRatio
```
public static float getFontRatio(Context context)
```
    Obtains the font ratio.
    
    参数:
    
    context - Indicates the application context.
    
    返回:
    
    Returns the font ratio.
    
    从以下版本开始:
    
    5
  - convertValueToInt
```
public static int convertValueToInt(String value,
                                    int defaultValue)
```
    Converts a value from a character string to an integer.
    If the value is empty, the value specified by defaultValue is returned.
    
    参数:
    
    value - Indicates the value to convert.
    
    defaultValue - Indicates the default value.
    
    返回:
    
    Returns the integer value after conversion.
  - convertValueToBlendMode
```
public static BlendMode convertValueToBlendMode(String value,
                                                BlendMode defaultValue)
```
    Converts a value from a character string to an integer.
    If the value is empty, the value specified by defaultValue is returned.
    
    参数:
    
    value - Indicates the value to convert.
    
    defaultValue - Indicates the default value.
    
    返回:
    
    Returns the BlendMode value after conversion.
    
    从以下版本开始:
    
    7
  - convertValueToColorMatrix
```
public static ColorMatrix convertValueToColorMatrix(int value)
```
    Converts a value from an int to a ColorMatrix object.
    
    参数:
    
    value - Indicates the int color value to convert.
    
    返回:
    
    Returns the ColorMatrix value after conversion.
    
    从以下版本开始:
    
    7
  - convertValueToBoolean
```
public static boolean convertValueToBoolean(String value,
                                            boolean defaultValue)
```
    Converts a value from a character string to a Boolean value.
    Ensure that the Boolean value is either true or false. Otherwise, an exception will occur.
    
    参数:
    
    value - Indicates the value to convert.
    
    defaultValue - Indicates the default value.
    
    返回:
    
    Returns the Boolean value after conversion.
  - convertValueToFloat
```
public static float convertValueToFloat(String value,
                                        float defaultValue)
```
    Converts a character string to a floating point value. If the character string does not exist, the value specified by defaultValue is returned.
    
    参数:
    
    value - Indicates the character string to convert.
    
    defaultValue - Indicates the default value.
    
    返回:
    
    Returns the floating point value after conversion.
  - convertValueToLong
```
public static long convertValueToLong(String value,
                                      long defaultValue)
```
    Converts a string to a long value.
    
    参数:
    
    value - Indicates the string value.
    
    defaultValue - Indicates the default value.
    
    返回:
    
    Returns the long value after conversion.
  - convertValueToElement
```
public static Element convertValueToElement(String value)
```
    Converts a string into a Element object.
    
    参数:
    
    value - Indicates the string to convert.
    
    返回:
    
    Returns the Element object.
    
    从以下版本开始:
    
    3
  - convertValueToColor
```
public static Color convertValueToColor(String value)
```
    Converts a string into a Color object.
    
    参数:
    
    value - Indicates the string to convert.
    
    返回:
    
    Returns the Color object.
    
    从以下版本开始:
    
    3
  - convertDimensionToPix
```
public static int convertDimensionToPix(String value,
                                        float density,
                                        int defaultValue)
```
    Converts a dimension value to a number of pixels.
    
    参数:
    
    value - Indicates the dimension value to convert.
    
    density - Indicates the screen density.
    
    defaultValue - Indicates the default value.
    
    返回:
    
    Returns the number of pixels after conversion.
  - convertDimensionToPix
```
public static int convertDimensionToPix(Context context,
                                        String value,
                                        int defaultValue)
```
    Converts a dimension value into a pixel value.
    
    参数:
    
    context - Indicates the application context.
    
    value - Indicates the dimension value to convert.
    
    defaultValue - Indicates the default value.
    
    返回:
    
    Returns a pixel value.
    
    从以下版本开始:
    
    5
  - vp2px
```
public static int vp2px(float value,
                        float density)
```
    Converts a virtual pixel (vp) to a pixel value based on the screen density.
    
    参数:
    
    value - Indicates the vp value to convert.
    
    density - Indicates the screen density.
    
    返回:
    
    Returns a pixel value.
    
    从以下版本开始:
    
    4
    
    另请参阅:
    
    getDensity(Context)
  - vp2px
```
public static int vp2px(float value,
                        Context context)
```
    Converts a virtual pixel (vp) to a pixel value based on the screen context.
    
    参数:
    
    value - Indicates the vp value to convert.
    
    context - Indicates the screen context.
    
    返回:
    
    Returns a pixel value.
    
    从以下版本开始:
    
    4
  - fp2px
```
public static int fp2px(float value,
                        float density)
```
    Converts a font-size pixel (fp) to a pixel value based on the screen density.
    
    参数:
    
    value - Indicates the fp value to convert.
    
    density - Indicates the screen density.
    
    返回:
    
    Returns a pixel value.
    
    从以下版本开始:
    
    4
    
    另请参阅:
    
    getDensity(Context)
  - fp2px
```
public static int fp2px(float value,
                        float density,
                        float fontRatio)
```
    Converts a font-size pixel (fp) value to a pixel value based on the screen density and font ratio.
    
    参数:
    
    value - Indicates the fp value to convert.
    
    density - Indicates the screen density.
    
    fontRatio - Indicates the font ratio.
    
    返回:
    
    Returns a pixel value.
    
    从以下版本开始:
    
    5
    
    另请参阅:
    
    getDensity(Context), getFontRatio(Context)
  - fp2px
```
public static int fp2px(float value,
                        Context context)
```
    Converts a font-size pixel (fp) to a pixel value based on the screen context.
    
    参数:
    
    value - Indicates the fp value to convert.
    
    context - Indicates the screen context.
    
    返回:
    
    Returns a pixel value.
    
    从以下版本开始:
    
    4
  - px2vp
```
public static float px2vp(int value,
                          Context context)
```
    Converts a pixel to a virtual pixel based on the screen context.
    
    参数:
    
    value - Indicates the pixel to convert.
    
    context - Indicates the screen context.
    
    返回:
    
    Returns a virtual pixel.
    
    从以下版本开始:
    
    7
  - px2fp
```
public static float px2fp(int value,
                          Context context)
```
    Converts a pixel to a font-size pixel based on the screen context.
    
    参数:
    
    value - Indicates the pixel to convert.
    
    context - Indicates the screen context.
    
    返回:
    
    Returns a font-size pixel.
    
    从以下版本开始:
    
    7

类 AttrHelper

构造器概要

方法概要

从类继承的方法 java.lang.Object

构造器详细资料

AttrHelper

方法详细资料

getDensity

getFontRatio

convertValueToInt

convertValueToBlendMode

convertValueToColorMatrix

convertValueToBoolean

convertValueToFloat

convertValueToLong

convertValueToElement

convertValueToColor

convertDimensionToPix

convertDimensionToPix

vp2px

vp2px

fp2px

fp2px

fp2px

px2vp

px2fp