是否可以在Android TextView周围绘制边框?


当前回答

我通过扩展文本视图并手动绘制边框解决了这个问题。我甚至添加了这样的选项,您可以选择边框是虚线还是虚线。

public class BorderedTextView extends TextView {
        private Paint paint = new Paint();
        public static final int BORDER_TOP = 0x00000001;
        public static final int BORDER_RIGHT = 0x00000002;
        public static final int BORDER_BOTTOM = 0x00000004;
        public static final int BORDER_LEFT = 0x00000008;

        private Border[] borders;

        public BorderedTextView(Context context, AttributeSet attrs, int defStyle) {
            super(context, attrs, defStyle);
            init();
        }

        public BorderedTextView(Context context, AttributeSet attrs) {
            super(context, attrs);
            init();
        }

        public BorderedTextView(Context context) {
            super(context);
            init();
        }
        private void init(){
            paint.setStyle(Paint.Style.STROKE);
            paint.setColor(Color.BLACK);
            paint.setStrokeWidth(4);        
        }
        @Override
        protected void onDraw(Canvas canvas) {
            super.onDraw(canvas);
            if(borders == null) return;

            for(Border border : borders){
                paint.setColor(border.getColor());
                paint.setStrokeWidth(border.getWidth());

                if(border.getStyle() == BORDER_TOP){
                    canvas.drawLine(0, 0, getWidth(), 0, paint);                
                } else
                if(border.getStyle() == BORDER_RIGHT){
                    canvas.drawLine(getWidth(), 0, getWidth(), getHeight(), paint);
                } else
                if(border.getStyle() == BORDER_BOTTOM){
                    canvas.drawLine(0, getHeight(), getWidth(), getHeight(), paint);
                } else
                if(border.getStyle() == BORDER_LEFT){
                    canvas.drawLine(0, 0, 0, getHeight(), paint);
                }
            }
        }

        public Border[] getBorders() {
            return borders;
        }

        public void setBorders(Border[] borders) {
            this.borders = borders;
        }
}

边框类:

public class Border {
    private int orientation;
    private int width;
    private int color = Color.BLACK;
    private int style;
    public int getWidth() {
        return width;
    }
    public void setWidth(int width) {
        this.width = width;
    }
    public int getColor() {
        return color;
    }
    public void setColor(int color) {
        this.color = color;
    }
    public int getStyle() {
        return style;
    }
    public void setStyle(int style) {
        this.style = style;
    }
    public int getOrientation() {
        return orientation;
    }
    public void setOrientation(int orientation) {
        this.orientation = orientation;
    }
    public Border(int Style) {
        this.style = Style;
    }
}

希望这对某人有所帮助:)

其他回答

有很多方法可以向textView添加边框。最简单的方法是创建一个自定义的可绘制文件,并将其设置为android:background=“@drawable/textview_bg”用于textview。

textview_bg.xml将位于Drawables下,可以是这样的。您可以有一个实心或渐变背景(如果不需要的话,也可以没有背景)、添加角半径的角和添加边框的笔划。

textview_bg.xml

<?xml version="1.0" encoding="utf-8"?>
    <shape xmlns:android="http://schemas.android.com/apk/res/android"
        android:shape="rectangle">

        <corners
            android:radius="@dimen/dp_10"/>

        <gradient
            android:angle="225"
            android:endColor="#FFFFFF"
            android:startColor="#E0E0E0" />

        <stroke
            android:width="2dp"
            android:color="#000000"/>

    </shape>

我找到的最简单的解决方案(而且实际可行):

<TextView
    ...
    android:background="@android:drawable/editbox_background" />

您可以在代码中添加以下内容:

<shape xmlns:android="http://schemas.android.com/apk/res/android"
       android:shape="rectangle" >
    <solid android:color="#ffffff" />
    <stroke android:width="1dip" android:color="#4fa5d5"/>
</shape>

简单的方法是为TextView添加视图。底部边框线示例:

<LinearLayout android:orientation="vertical"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent">
    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:layout_marginLeft="10dp"
        android:text="@string/title"
        android:id="@+id/title_label"
        android:gravity="center_vertical"/>
    <View
        android:layout_width="fill_parent"
        android:layout_height="0.2dp"
        android:id="@+id/separator"
        android:visibility="visible"
        android:background="@android:color/darker_gray"/>

</LinearLayout>

对于其他方向的边框,请调整分隔符视图的位置。

这是我的“简单”助手类,它返回带有边框的ImageView。只需将其放在utils文件夹中,并按如下方式调用:

ImageView selectionBorder = BorderDrawer.generateBorderImageView(context, borderWidth, borderHeight, thickness, Color.Blue);

这是代码。

/**
 * Because creating a border is Rocket Science in Android.
 */
public class BorderDrawer
{
    public static ImageView generateBorderImageView(Context context, int borderWidth, int borderHeight, int borderThickness, int color)
    {
        ImageView mask = new ImageView(context);

        // Create the square to serve as the mask
        Bitmap squareMask = Bitmap.createBitmap(borderWidth - (borderThickness*2), borderHeight - (borderThickness*2), Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(squareMask);

        Paint paint = new Paint();
        paint.setStyle(Paint.Style.FILL);
        paint.setColor(color);
        canvas.drawRect(0.0f, 0.0f, (float)borderWidth, (float)borderHeight, paint);

        // Create the darkness bitmap
        Bitmap solidColor = Bitmap.createBitmap(borderWidth, borderHeight, Bitmap.Config.ARGB_8888);
        canvas = new Canvas(solidColor);

        paint.setStyle(Paint.Style.FILL);
        paint.setColor(color);
        canvas.drawRect(0.0f, 0.0f, borderWidth, borderHeight, paint);

        // Create the masked version of the darknessView
        Bitmap borderBitmap = Bitmap.createBitmap(borderWidth, borderHeight, Bitmap.Config.ARGB_8888);
        canvas = new Canvas(borderBitmap);

        Paint clearPaint = new Paint();
        clearPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));

        canvas.drawBitmap(solidColor, 0, 0, null);
        canvas.drawBitmap(squareMask, borderThickness, borderThickness, clearPaint);

        clearPaint.setXfermode(null);

        ImageView borderView = new ImageView(context);
        borderView.setImageBitmap(borderBitmap);

        return borderView;
    }
}