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
以下是我的解决方案:
<com.myproject.ui.RadiusCornerImageView
android:id="@+id/imageViewPhoto"
android:layout_width="160dp"
android:layout_height="160dp"
app:corner_radius_dp="5"
app:corner_radius_position="top"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
在java代码中:
public class RadiusCornerImageView extends android.support.v7.widget.AppCompatImageView {
private int cornerRadiusDP = 0; // dp
private int corner_radius_position;
public RadiusCornerImageView(Context context) {
super(context);
}
public RadiusCornerImageView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public RadiusCornerImageView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
TypedArray typeArray = context.getTheme().obtainStyledAttributes(attrs, R.styleable.RadiusCornerImageView, 0, 0);
try {
cornerRadiusDP = typeArray.getInt(R.styleable.RadiusCornerImageView_corner_radius_dp, 0);
corner_radius_position = typeArray.getInteger(R.styleable.RadiusCornerImageView_corner_radius_position, 0);
} finally {
typeArray.recycle();
}
}
@Override
protected void onDraw(Canvas canvas) {
float radiusPx = AndroidUtil.dpToPx(getContext(), cornerRadiusDP);
Path clipPath = new Path();
RectF rect = null;
if (corner_radius_position == 0) { // all
// round corners on all 4 angles
rect = new RectF(0, 0, this.getWidth(), this.getHeight());
} else if (corner_radius_position == 1) {
// round corners only on top left and top right
rect = new RectF(0, 0, this.getWidth(), this.getHeight() + radiusPx);
} else {
throw new IllegalArgumentException("Unknown corner_radius_position = " + corner_radius_position);
}
clipPath.addRoundRect(rect, radiusPx, radiusPx, Path.Direction.CW);
canvas.clipPath(clipPath);
super.onDraw(canvas);
}
}
其他回答
您应该扩展ImageView并绘制自己的圆角矩形。
如果你想在图像周围添加一个框架,你也可以在布局中将圆形框架叠加在图像视图的顶部。
例如,通过使用FrameLayout将帧叠加到原始图像上。FrameLayout的第一个元素将是你想要显示的图像。然后添加另一个ImageView与框架。第二个ImageView将显示在原始ImageView的顶部,因此Android将在原始ImageView上方绘制它的内容。
这是相当晚的响应,但对于任何其他人正在寻找这个,您可以执行以下代码手动圆角的图像。
http://www.ruibm.com/?p=184
这不是我的代码,但我用过它,它的工作非常出色。我将它用作ImageHelper类中的一个助手,并对它进行了一点点扩展,以便传入给定图像所需的羽化量。
最终代码如下所示:
package com.company.app.utils;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Bitmap.Config;
import android.graphics.PorterDuff.Mode;
public class ImageHelper {
public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, int pixels) {
Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap
.getHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(output);
final int color = 0xff424242;
final Paint paint = new Paint();
final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
final RectF rectF = new RectF(rect);
final float roundPx = pixels;
paint.setAntiAlias(true);
canvas.drawARGB(0, 0, 0, 0);
paint.setColor(color);
canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
canvas.drawBitmap(bitmap, rect, rect, paint);
return output;
}
}
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>
科特林
import android.graphics.BitmapFactory
import android.os.Bundle
import android.support.v4.graphics.drawable.RoundedBitmapDrawableFactory
import kotlinx.android.synthetic.main.activity_main.*
val bitmap = BitmapFactory.decodeResource(resources, R.drawable.myImage)
val rounded = RoundedBitmapDrawableFactory.create(resources, bitmap)
rounded.cornerRadius = 20f
profileImageView.setImageDrawable(rounded)
为了使ImageView成为圆形,我们可以改变拐角半径:
rounded.isCircular = true
对于圆形边界使用下面的代码
<com.google.android.material.card.MaterialCardView
android:id="@+id/circle"
android:layout_width="45dp"
android:layout_height="45dp"
android:layout_marginStart="5dp"
app:cardCornerRadius="25dp"
app:strokeColor="@color/colorDarkGreen"
app:strokeWidth="1dp">
<ImageView
android:id="@+id/toolbarProfile"
android:scaleType="fitXY"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:src="@drawable/avater" />
</com.google.android.material.card.MaterialCardView>