带有圆角的ImageView中的位图

Question

我有一个ImageView,我想用它rounded corners.

我用这个:

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle"> 
    <solid  android:color="@null"/>    

    <stroke android:width="1dp"
            android:color="#ff000000"/>


    <corners android:radius="62px"/> 
</shape>

并将此代码设置为我的imageview的背景.它可以工作,但我放在它上面的src图像ImageView是走出边界而不适应新的形状.

我该如何解决这个问题？

Answer 1

试试这个:

public class CustomImageView extends ImageView {

    public static float radius = 18.0f;  

    public CustomImageView(Context context) {
        super(context);
    }

    public CustomImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public CustomImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        //float radius = 36.0f;  
        Path clipPath = new Path();
        RectF rect = new RectF(0, 0, this.getWidth(), this.getHeight());
        clipPath.addRoundRect(rect, radius, radius, Path.Direction.CW);
        canvas.clipPath(clipPath);
        super.onDraw(canvas);
    }
}

和

<your.pack.name.CustomImageView
                android:id="@+id/selectIcon"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerInParent="true"
                android:scaleType="centerCrop" />

CustomImageView  iconImage = (CustomImageView )findViewById(R.id.selectIcon);
iconImage.setImageBitmap(bitmap);

要么,

ImageView iv= new CustomImageView(this);
iv.setImageResource(R.drawable.pic);

Answer 2

奇怪的是,这里没有人提到Android支持库v4 中的RoundedBitmapDrawable.对我来说,这是获得无边框圆角的最简单方法.以下是用法示例:

RoundedBitmapDrawable roundedBitmapDrawable = RoundedBitmapDrawableFactory.create(getResources(), bitmap);
final float roundPx = (float) bitmap.getWidth() * 0.06f;
roundedBitmapDrawable.setCornerRadius(roundPx);

Answer 3

使用canvas创建一个舍入到位图的函数.

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;
}

了解更多信息:> 这里

Answer 4

接受的答案使用路径剪辑,但它不支持抗锯齿.请参阅Romain Guy对其帖子的评论."路径裁剪不支持抗锯齿,你会得到锯齿状的边缘."

http://www.curious-creature.com/2012/12/11/android-recipe-1-image-with-rounded-corners/

有一个很好的库(vinc3m1的RoundedImageView)在ImageView上支持圆角,但它只支持每个角上相同的半径.所以我做了一个你可以在每个角上设置不同的半径.

它不依赖于路径裁剪,也不依赖于重绘.它只用canvas.drawPath()方法绘制一次.所以我终于得到了我想要的结果如下.

请参阅:https://github.com/pungrue26/SelectableRoundedImageView

Answer 5

对我来说，下面的方法很神奇。:) 此方法接受一个位图对象并将其返回为圆角。roundPx是您想要的舍入像素数：

public static Bitmap getRoundedCornerBitmap(Bitmap bitmap) {
    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 = 12;

    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;
}

...或者您可以使用此库代替ImageView，而无需任何进一步的编码。

Answer 6

如果您需要制作具有不同圆角半径的位图，我建议您遵循以下代码：

private static Bitmap createRoundedRectBitmap(@NonNull Bitmap bitmap,
                                float topLeftCorner, float topRightCorner,
                                float bottomRightCorner, float bottomLeftCorner) {
    Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), 
                                        Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(output);

    final int color = Color.WHITE;
    final Paint paint = new Paint();
    final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
    final RectF rectF = new RectF(rect);
    Path path = new Path();
    float[] radii = new float[]{
            topLeftCorner, bottomLeftCorner,
            topRightCorner, topRightCorner,
            bottomRightCorner, bottomRightCorner,
            bottomLeftCorner, bottomLeftCorner
    };

    paint.setAntiAlias(true);
    canvas.drawARGB(0, 0, 0, 0);
    paint.setColor(color);
    path.addRoundRect(rectF, radii, Path.Direction.CW);
    canvas.drawPath(path, paint);
    paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
    canvas.drawBitmap(bitmap, rect, rect, paint);
    return output;
}

Answer 7

如果您还需要边框,则:1.您可以使用带有透明主体和外部白色的圆形框图像.例如:

并将其与目标图像一起使用,如下所示:

<FrameLayout
android:layout_width="100px"
android:layout_height="100px" >
<ImageView
        android:id="@+id/targetImage"
        android:layout_width="100px"
        android:layout_height="100px"
        android:src="@drawable/app_icon"
        android:layout_gravity="center" />
<ImageView
        android:id="@+id/boxImage"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:scaleType="fitXY"
        android:src="@drawable/box" />

2. 添加CardView作为父布局ImageView也是一个很好的解决方案.