之前做標籤的時候，做過包圍整個控制元件的虛線邊框，當時利用了shape來實現

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <corners android:radius="4dp"/>
    <stroke android:width="1dp" android:dashWidth="4dp" android:dashGap="4dp"/>
</shape>

這次想直接給一個虛線的分割線。按照慣性思維我也用shape編寫了一個檔案

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="line">
    <stroke
        android:width="3px"
        android:color="#FF0000"
        android:dashWidth="10px"
        android:dashGap="10px" />
</shape>

哈哈哈，依照之前的思想把它設定為一個view的背景，

http://blog.csdn.net/qiuqingpo/article/details/40394677

 我照著測試了，也是沒有效果。就想著直接自定義吧，感謝作者SmallLee

https://github.com/SmallLee/DashView   成功解救了我

這個自定義view的屬性

<!--自定義虛線屬性-->
    <declare-styleable name="DashView">
        <attr name="dashWidth" format="dimension" />
        <attr name="lineWidth" format="dimension" />
        <attr name="lineHeight" format="dimension" />
        <attr name="lineColor" format="color" />
        <attr name="dashOrientation" format="integer" />
    </declare-styleable>
 

自定義控制元件程式碼

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.view.View;

/**
 * Created by Administrator on 2016/8/26.
 */
public class DashView extends View {
    private static final String TAG = "DashView";
    public static final int DEFAULT_DASH_WIDTH = 100;
    public static final int DEFAULT_LINE_WIDTH = 100;
    public static final int DEFAULT_LINE_HEIGHT = 10;
    public static final int DEFAULT_LINE_COLOR = 0x9E9E9E;

    /**虛線的方向*/
    public static final int ORIENTATION_HORIZONTAL = 0;
    public static final int ORIENTATION_VERTICAL = 1;
    /**預設為水平方向*/
    public static final int DEFAULT_DASH_ORIENTATION = ORIENTATION_HORIZONTAL;
    /**間距寬度*/
    private float dashWidth;
    /**線段高度*/
    private float lineHeight;
    /**線段寬度*/
    private float lineWidth;
    /**線段顏色*/
    private int lineColor;
    private int dashOrientation;

    private Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
    private int widthSize;
    private int heightSize;

    public DashView(Context context) {
        this(context,null);
    }

    public DashView(Context context, AttributeSet attrs) {
        super(context, attrs);
        TypedArray typedArray = context.obtainStyledAttributes(attrs,R.styleable.DashView);
        dashWidth = typedArray.getDimension(R.styleable.DashView_dashWidth,DEFAULT_DASH_WIDTH);
        lineHeight = typedArray.getDimension(R.styleable.DashView_lineHeight, DEFAULT_LINE_HEIGHT);
        lineWidth = typedArray.getDimension(R.styleable.DashView_lineWidth, DEFAULT_LINE_WIDTH);
        lineColor = typedArray.getColor(R.styleable.DashView_lineColor, DEFAULT_LINE_COLOR);
        dashOrientation = typedArray.getInteger(R.styleable.DashView_dashOrientation,DEFAULT_DASH_ORIENTATION);
        mPaint.setColor(lineColor);
        mPaint.setStrokeWidth(lineHeight);
        typedArray.recycle();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        widthSize = MeasureSpec.getSize(widthMeasureSpec)-getPaddingLeft()-getPaddingRight();
        heightSize = MeasureSpec.getSize(heightMeasureSpec - getPaddingTop() - getPaddingBottom());
        if(dashOrientation == ORIENTATION_HORIZONTAL){
            ////不管在佈局檔案中虛線高度設定為多少，控制元件的高度統一設定為線段的高度
            setMeasuredDimension(widthSize, (int) lineHeight);
        }else{
            //當為豎直方向時，控制元件寬度設定為虛線的高度
           setMeasuredDimension((int) lineHeight, heightSize);
        }

    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        switch (dashOrientation){
            case ORIENTATION_VERTICAL:
                drawVerticalLine(canvas);
                break;
            default:
                drawHorizontalLine(canvas);
        }
    }

    /**
     * 畫水平方向虛線
     * @param canvas
     */
    public void drawHorizontalLine(Canvas canvas){
        float totalWidth = 0;
        canvas.save();
        float[] pts = {0,0,lineWidth,0};
        //在畫線之前需要先把畫布向下平移辦個線段高度的位置，目的就是為了防止線段只畫出一半的高度
        //因為畫線段的起點位置線上段左下角
        canvas.translate(0,lineHeight/2);
        while(totalWidth<=widthSize){
            canvas.drawLines(pts,mPaint);
            canvas.translate(lineWidth + dashWidth,0);
            totalWidth += lineWidth + dashWidth;
        }
        canvas.restore();
    }

    /**
     * 畫豎直方向虛線
     * @param canvas
     */
    public void drawVerticalLine(Canvas canvas){
        float totalWidth = 0;
        canvas.save();
        float[] pts = {0,0,0,lineWidth};
        //在畫線之前需要先把畫布向右平移半個線段高度的位置，目的就是為了防止線段只畫出一半的高度
        //因為畫線段的起點位置線上段左下角
        canvas.translate(lineHeight/2,0);
        while(totalWidth<=heightSize){
            canvas.drawLines(pts,mPaint);
            canvas.translate(0,lineWidth + dashWidth);
            totalWidth += lineWidth + dashWidth;
        }
        canvas.restore();
    }
}

特次記錄一下

我在佈局中的使用

 <com.xxxxxxx.widget.DashView
        android:layout_width="match_parent"
        android:layout_height="0.5dp"
        android:layout_marginLeft="10dp"
        app:dashOrientation="0"
        app:dashWidth="2dp"
        app:lineColor="@color/grar_ef"
        app:lineHeight="1dp"
        app:lineWidth="4dp" />

我還是想知道為什麼我用解決shape的方法就不顯虛線，有時間繼續測試！！！！！