Java 如何在圆形imageView android上添加阴影和边框？

Z时代
2024-01-10
分类：问答

我用以下问题创建了CircularImageView：在android中创建圆形图像视图

在GitHub上下载项目

1）这是CircularImageView类：

public class CircularImageView extends ImageView {
    public CircularImageView(Context context) {
        super(context);
    }
    public CircularImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }
    public CircularImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }
    @Override
    protected void onDraw(Canvas canvas) {
        Drawable drawable = getDrawable();
        if (drawable == null) {
            return;
        }
        if (getWidth() == 0 || getHeight() == 0) {
            return; 
        }
        Bitmap b =  ((BitmapDrawable)drawable).getBitmap() ;
        Bitmap bitmap = b.copy(Bitmap.Config.ARGB_8888, true);      
        Bitmap roundBitmap =  getCroppedBitmap(bitmap, getWidth());
        canvas.drawBitmap(roundBitmap, 0, 0, null);
    }
    public static Bitmap getCroppedBitmap(Bitmap bmp, int radius) {
        Bitmap sbmp;
        if(bmp.getWidth() != radius || bmp.getHeight() != radius)
            sbmp = Bitmap.createScaledBitmap(bmp, radius, radius, false);
        else
            sbmp = bmp;
        Bitmap output = Bitmap.createBitmap(sbmp.getWidth(), sbmp.getHeight(), Bitmap.Config.ARGB_8888);
        final Rect rect = new Rect(0, 0, sbmp.getWidth(), sbmp.getHeight());
        Paint paint = new Paint();
        paint.setAntiAlias(true);
        paint.setFilterBitmap(true);
        paint.setDither(true);      
        paint.setColor(Color.parseColor("#BAB399"));
        Canvas c = new Canvas(output);        
        c.drawARGB(0, 0, 0, 0);
        c.drawCircle(sbmp.getWidth() / 2+0.7f, sbmp.getHeight() / 2+0.7f, sbmp.getWidth() / 2+0.1f, paint);
        paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
        c.drawBitmap(sbmp, rect, rect, paint);
        return output;
    }
}

2）我在我的布局中使用这样的：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#cccccc"
    android:gravity="center"
    android:orientation="vertical"
    android:padding="10dp" >
    <com.mikhaellopez.circularimageview.CircularImageView
        android:id="@+id/imageViewCircular"
        android:layout_width="@dimen/image_view_size"
        android:layout_height="@dimen/image_view_size"
        android:layout_gravity="center"
        android:background="@drawable/border"
        android:src="@drawable/image" />
</LinearLayout>

你可以通过gradle依赖关系使用或下载带有所有修复程序的GitHub库 CircularImageView：

compile ‘com.mikhaellopez:circularimageview:2.0.1’

回答：

我修改了在此处找到的CircularImageView，以实现所需的功能。

为了在边框周围创建阴影，我只使用了以下两行：

this.setLayerType(LAYER_TYPE_SOFTWARE, paintBorder);
paintBorder.setShadowLayer(4.0f, 0.0f, 2.0f, Color.BLACK);

setLayerType由于HoneyComb以及更高版本上的硬件加速，你需要这样做。我尝试时没有它就无法工作。

这是完整的代码：

import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapShader;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Shader;
import android.graphics.drawable.BitmapDrawable;
import android.util.AttributeSet;
import android.widget.ImageView;
public class CircularImageView extends ImageView
{
    private int borderWidth = 4;
    private int viewWidth;
    private int viewHeight;
    private Bitmap image;
    private Paint paint;
    private Paint paintBorder;
    private BitmapShader shader;
    public CircularImageView(Context context)
    {
        super(context);
        setup();
    }
    public CircularImageView(Context context, AttributeSet attrs)
    {
        super(context, attrs);
        setup();
    }
    public CircularImageView(Context context, AttributeSet attrs, int defStyle)
    {
        super(contex