在Android中,ImageView默认是一个矩形。如何使它成为一个圆角矩形(剪辑我的位图的所有4个角为圆角矩形)在ImageView?
请注意,从2021年起,只需使用ShapeableImageView
在Android中,ImageView默认是一个矩形。如何使它成为一个圆角矩形(剪辑我的位图的所有4个角为圆角矩形)在ImageView?
请注意,从2021年起,只需使用ShapeableImageView
当前回答
对我来说,下面的解决方案似乎是最优雅的:
ImageView roundedImageView = new ImageView (getContext());
roundedImageView.setClipToOutline(true);
Bitmap bitmap = AppUtil.decodeSampledBitmapFromResource(new File(valueListItemsView.getImagePath()), width, height);
roundedImageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
roundedImageView.setImageBitmap(bitmap);
roundedImageView.setBackgroundResource(R.drawable.rounded_corner);
而可绘制的rounded_corner.xml的代码是:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<solid android:color="@color/colorAccent" />
<corners android:radius="24dp" />
</shape>
其他回答
试试这个
Bitmap finalBitmap;
if (bitmap.getWidth() != radius || bitmap.getHeight() != radius)
finalBitmap = Bitmap.createScaledBitmap(bitmap, radius, radius,
false);
else
finalBitmap = bitmap;
Bitmap output = Bitmap.createBitmap(finalBitmap.getWidth(),
finalBitmap.getHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(output);
final Paint paint = new Paint();
final Rect rect = new Rect(0, 0, finalBitmap.getWidth(),
finalBitmap.getHeight());
paint.setAntiAlias(true);
paint.setFilterBitmap(true);
paint.setDither(true);
canvas.drawARGB(0, 0, 0, 0);
paint.setColor(Color.parseColor("#BAB399"));
canvas.drawCircle(finalBitmap.getWidth() / 2 + 0.7f,
finalBitmap.getHeight() / 2 + 0.7f,
finalBitmap.getWidth() / 2 + 0.1f, paint);
paint.setXfermode(new PorterDuffXfermode(
android.graphics.PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(finalBitmap, rect, rect, paint);
return output;
如果你正在使用格莱德图书馆,这将是有帮助的:
Glide.with(getApplicationContext())
.load(image_url)
.asBitmap()
.centerCrop()
.into(new BitmapImageViewTarget(imageView) {
@Override
protected void setResource(Bitmap resource) {
RoundedBitmapDrawable circularBitmapDrawable =
RoundedBitmapDrawableFactory.create(getApplicationContext().getResources(), resource);
circularBitmapDrawable.setCornerRadius(dpToPx(10));
circularBitmapDrawable.setAntiAlias(true);
imageView.setImageDrawable(circularBitmapDrawable);
}
});
public int dpToPx(int dp) {
DisplayMetrics displayMetrics = getApplicationContext().getResources().getDisplayMetrics();
return Math.round(dp * (displayMetrics.xdpi / DisplayMetrics.DENSITY_DEFAULT));
}
另一种简单的方法是使用一个带有角半径的CardView和一个ImageView在里面:
<androidx.cardview.widget.CardView
android:layout_width="match_parent"
android:layout_height="match_parent"
app:cardCornerRadius="8dp"
android:layout_margin="5dp"
android:elevation="10dp">
<ImageView
android:id="@+id/roundedImageView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:src="@drawable/image"
android:background="@color/white"
android:scaleType="centerCrop"
/>
</androidx.cardview.widget.CardView>
这不是确切的答案,但它是一个类似的解决方案。它可能会帮助那些和我有同样遭遇的人。
我的图像是一个应用程序logo,它的背景是透明的,我正在应用XML渐变作为图像背景。我在imageView中添加了必要的padding/margin,然后添加了这个作为我的背景:
<?xml version="1.0" encoding="utf-8"?>
<!-- This file defines the gradient used on the background of the main activity. -->
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<shape>
<gradient
android:type="linear"
android:startColor="@color/app_color_light_background"
android:endColor="@color/app_color_disabled"
android:angle="90" />
<!-- Round the top corners. -->
<corners
android:topLeftRadius="@dimen/radius_small"
android:topRightRadius="@dimen/radius_small" />
</shape>
</item>
</selector>
如果你的图片在互联网上,最好的方法是使用glide和RoundedBitmapDrawableFactory(来自API 21 -但在支持库中可用),如下所示:
Glide.with(ctx).load(url).asBitmap().centerCrop().into(new BitmapImageViewTarget(imageView) {
@Override
protected void setResource(Bitmap res) {
RoundedBitmapDrawable bitmapDrawable =
RoundedBitmapDrawableFactory.create(ctx.getResources(), res);
bitmapDrawable.setCircular(true);//comment this line and uncomment the next line if you dont want it fully cricular
//circularBitmapDrawable.setCornerRadius(cornerRadius);
imageView.setImageDrawable(bitmapDrawable);
}
});