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
芬兰湾的科特林版:
@GlideExtension
object GamersGeekGlideExtension {
@NonNull
@JvmStatic
@GlideOption
fun roundedCorners(options: BaseRequestOptions<*>, context: Context, cornerRadius: Int): BaseRequestOptions<*> {
val px =
(cornerRadius * (context.resources.displayMetrics.xdpi / DisplayMetrics.DENSITY_DEFAULT)).roundToInt()
return options.transforms(RoundedCorners(px))
}
}
注意:Glide扩展现在需要BaseRequestOptions而不是RequestOptions。此外,它与@Sir Codesalot答案在kotlin中转换的函数相同。
其他回答
我已经通过自定义ImageView完成:
public class RoundRectCornerImageView extends ImageView {
private float radius = 18.0f;
private Path path;
private RectF rect;
public RoundRectCornerImageView(Context context) {
super(context);
init();
}
public RoundRectCornerImageView(Context context, AttributeSet attrs) {
super(context, attrs);
init();
}
public RoundRectCornerImageView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init();
}
private void init() {
path = new Path();
}
@Override
protected void onDraw(Canvas canvas) {
rect = new RectF(0, 0, this.getWidth(), this.getHeight());
path.addRoundRect(rect, radius, radius, Path.Direction.CW);
canvas.clipPath(path);
super.onDraw(canvas);
}
}
使用方法:
<com.mypackage.RoundRectCornerImageView
android:id="@+id/imageView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/image"
android:scaleType="fitXY" />
输出:
希望这对你有所帮助。
我知道这个问题已经过时了,但这里有另一种更简单的四舍五入图像的方法:
这是一种编程方法。
创造你的空白……
} public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, int pixels) { Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Bitmap.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(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(bitmap, rect, rect, paint); return output;
加载图像,然后设置圆角
imageview1.setImageResource(R.drawable.yourimage);
Bitmap bm = ((android.graphics.drawable.BitmapDrawable) imageview1.getDrawable()).getBitmap();
imageview1.setImageBitmap(getRoundedCornerBitmap(bm, 30));
以30为半径,你会得到这样的结果:
不管我的图像看起来如何,它只是一个放大的小图标
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;
}
}
}
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
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);
}
}