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>
其他回答
为什么不在draw()中进行剪辑?
以下是我的解决方案:
用剪切扩展RelativeLayout 将ImageView(或其他视图)放入布局中:
代码:
public class RoundRelativeLayout extends RelativeLayout {
private final float radius;
public RoundRelativeLayout(Context context, AttributeSet attrs) {
super(context, attrs);
TypedArray attrArray = context.obtainStyledAttributes(attrs,
R.styleable.RoundRelativeLayout);
radius = attrArray.getDimension(
R.styleable.RoundRelativeLayout_radius, 0);
}
private boolean isPathValid;
private final Path path = new Path();
private Path getRoundRectPath() {
if (isPathValid) {
return path;
}
path.reset();
int width = getWidth();
int height = getHeight();
RectF bounds = new RectF(0, 0, width, height);
path.addRoundRect(bounds, radius, radius, Direction.CCW);
isPathValid = true;
return path;
}
@Override
protected void dispatchDraw(Canvas canvas) {
canvas.clipPath(getRoundRectPath());
super.dispatchDraw(canvas);
}
@Override
public void draw(Canvas canvas) {
canvas.clipPath(getRoundRectPath());
super.draw(canvas);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int oldWidth = getMeasuredWidth();
int oldHeight = getMeasuredHeight();
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
int newWidth = getMeasuredWidth();
int newHeight = getMeasuredHeight();
if (newWidth != oldWidth || newHeight != oldHeight) {
isPathValid = false;
}
}
}
我使用路径在图像画布上只画角。(我需要没有位图内存分配的解决方案)
@Override
protected void onDraw(final Canvas canvas) {
super.onDraw(canvas);
if (!hasRoundedCorners()) return;
mPaint.setStyle(Paint.Style.FILL);
mPaint.setStrokeWidth(0);
Path path = new Path();
path.setFillType(Path.FillType.INVERSE_WINDING);
path.addRoundRect(new RectF(0, 0, getWidth(), getHeight()), mRadius, mRadius, Path.Direction.CCW);
canvas.drawPath(path, mPaint);
}
注意,你不应该在onDraw方法中分配任何新对象。此代码是概念验证,不应该在产品代码中这样使用
看到更多: https://medium.com/@przemek.materna/rounded-image-view-no-bitmap-reallocation-11a8b163484d
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>
它可以很容易地完成下面的形状。将其作为src添加到图像中。 如果你想删除边界,只需添加你的背景颜色的边界 :-)
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item
android:drawable="@drawable/img_area_one"
android:bottom="5dp"
android:left="5dp"
android:right="5dp"
android:top="5dp" />
<item>
<shape
android:padding="10dp"
android:shape="rectangle">
<corners
android:topLeftRadius="8dp"
android:topRightRadius="8dp"
/>
<stroke
android:width="5dp"
android:color="@color/white" />
</shape>
</item>
</layer-list>
你可以很容易地使用roundedImageView库:
compile 'com.makeramen:roundedimageview:2.3.0'
然后:
<com.makeramen.roundedimageview.RoundedImageView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="@+id/img_episode"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:elevation="7dp"
app:riv_border_color="@color/colorPrimary"
app:riv_border_width="1dip"
app:riv_corner_radius="10dip"
app:riv_mutate_background="true"
/>