android自定义View---生成虚线的View

1.在res/values/目录下 新建文件 attrs.xml

<?
 xml
 
version
=
 "1.0"
 
encoding
= 
"utf-8"
 ?>

<
 resources
>

 

    
<
declare-styleable 
name 
=
 "dashedline"
>

        
<
attr 
name 
=
 "lineColor"
 
format
=
 "color"
 
/>

    
</
declare-styleable 
>

 

</
 resources
>

 

2.创建自定义View，DashedLine.java

public 
class 
DashedLine 
extends
 View {

           
private
 Paint 
paint
 = 
null
;

           
private
 Path 
path
 = 
null
;

           
private
 PathEffect 
pe
 = 
null
;

 

           
public
 DashedLine(Context paramContext) {

                    
this
(paramContext, 
null
);

          }

 

           
public
 DashedLine(Context paramContext, AttributeSet paramAttributeSet) {

                    
super
(paramContext, paramAttributeSet);

    
               
  //通过R.styleable.dashedline获得我们在attrs.xml中定义的

//<declare-
styleable 
name="
dashedline
"> 
TypedArray

                   TypedArray a = paramContext.obtainStyledAttributes(paramAttributeSet, R.styleable.
 dashedline
);

                    
//我们在attrs.xml中<declare-
styleable 
name="
dashedline
">节点下

//添加了<attr name="lineColor" format="color" />

                    
//表示这个属性名为lineColor类型为color。当用户在布局文件中对它有设定值时

                    
//可通过TypedArray获得它的值当用户无设置值是采用默认值0XFF00000

                    
int
 lineColor = a.getColor(R.styleable. 
dashedline_lineColor
, 0XFF000000);

                   a.recycle();

                    
this
. 
paint
 = 
new
 Paint();

                    
this
. 
path
 = 
new
 Path();

                    
this
. 
paint
.setStyle(Paint.Style. 
STROKE
);

                    
this
. 
paint
.setColor(lineColor);

                    
this
. 
paint
.setAntiAlias( 
true
);

                    
this
. 
paint
.setStrokeWidth(BitmapHelper. 
dip2px
(getContext(), 2.0F));

                    
float
[] arrayOfFloat = 
new
 
float
[4];

                   arrayOfFloat[0] = BitmapHelper. 
dip2px
(getContext(), 2.0F);

                   arrayOfFloat[1] = BitmapHelper. 
dip2px
(getContext(), 2.0F);

                   arrayOfFloat[2] = BitmapHelper. 
dip2px
(getContext(), 2.0F);

                   arrayOfFloat[3] = BitmapHelper. 
dip2px
(getContext(), 2.0F);

                    
this
. 
pe
 = 
new
 DashPathEffect(arrayOfFloat, BitmapHelper.
dip2px
(getContext(), 1.0F));

          }

 

           
@Override

           
protected
 
void
 onDraw(Canvas canvas) {

                    
super
.onDraw(canvas);

                    
this
. 
path
.moveTo(0.0F, 0.0F);

                    
this
. 
path
.lineTo(getMeasuredWidth(), 0.0F);

                    
this
. 
paint
.setPathEffect( 
this
. 
pe
);

                   canvas.drawPath( 
this
. 
path
, 
this
. 
paint
);

          }

 

}

3.新建布局文件dashedline.xml

<?
 xml
 
version
=
 "1.0"
 
encoding
= 
"utf-8"
 ?>

<
 LinearLayout
 
xmlns:android
= 
"http://schemas.android.com/apk/res/android"

    
xmlns:dash
=
 "http://schemas.android.com/apk/res/com.example.martixtest"

    
android:layout_width
=
 "fill_parent"

    
android:layout_height
=
 "fill_parent"

    
android:background
=
 "#eee"

    
android:orientation
=
 "vertical"
 
>

 

    
<
com.example.martixtest.myview.DashedLine

        
android:layout_width
= 
"fill_parent"

        
android:layout_height
= 
"1dip"

        
android:layout_margin
= 
"10dip"

        
dash:lineColor
= 
"#ff50f8"
 
/>

 

    
<
com.example.martixtest.myview.DashedLine

        
android:layout_width
= 
"fill_parent"

        
android:layout_height
= 
"1dip"

        
android:layout_margin
= 
"10dip"
/>

 

    
<
com.example.martixtest.myview.DashedLine

        
android:layout_width
= 
"fill_parent"

        
android:layout_height
= 
"1dip"

        
android:layout_margin
= 
"10dip"

        
dash:lineColor
= 
"#f34f71"
 
/>

 

</
 LinearLayout
>

4.最终运行效果如下: