Picasso自定义位图变换方法

Question

我有一个将位图作为参数的函数，return 一个位图。

public Bitmap setRoundedCornes(Bitmap b, int l, int r, int t, int b)

在使用 Picasso 之前，我在应用程序中使用最终位图之前使用了此方法。

现在我正在使用 Picasso，但不确定如何应用此方法。

有人知道吗？

编辑

我现在有：

public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, int topLeftX, int topLeftY, int topRightX, int topRightY, int bottomRightX, int bottomRightY, int bottomLeftX, int bottomLeftY) {
    try {
        final Paint paint = new Paint();
        final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
        Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(output);
        // the float array passed to this function defines the x/y values of the corners
        // it starts top-left and works clockwise
        // so top-left-x, top-left-y, top-right-x etc
        RoundRectShape rrs = new RoundRectShape(new float[]{topLeftX, topLeftY, topRightX, topRightY, bottomRightX, bottomRightY, bottomLeftX, bottomLeftY}, null, null);
        canvas.drawARGB(0, 0, 0, 0);
        paint.setAntiAlias(true);
        paint.setColor(0xFF000000);
        rrs.resize(bitmap.getWidth(), bitmap.getHeight());
        rrs.draw(canvas, paint);
        paint.setXfermode(new PorterDuffXfermode(android.graphics.PorterDuff.Mode.SRC_IN));
        canvas.drawBitmap(bitmap, rect, rect, paint);
        return output;
    }catch(Exception e){

        return bitmap;
    }
}

和

public class MyTransform implements Transformation {
    @Override
    public Bitmap transform(Bitmap source) {
        //your logic to transform goes here
        return getRoundedCornerBitmap(source, 20, 20, 20, 20, 0, 0, 0, 0);
    }

    @Override
    public String key() {
        return "circle";
    }
}

Answer 1

是的，您可以像这样应用转换：

public class CropSquareTransformation implements Transformation {
  @Override public Bitmap transform(Bitmap source) {
    int size = Math.min(source.getWidth(), source.getHeight());
    int x = (source.getWidth() - size) / 2;
    int y = (source.getHeight() - size) / 2;
    Bitmap result = Bitmap.createBitmap(source, x, y, size, size);
    if (result != source) {
      source.recycle();
    }
    return result;
  }

  @Override public String key() { return "square()"; }
}

查看 Picasso 文档

Answer 2

为实现转换的转换创建 class

例如

public class MyTransform implements Transformation {
    @Override
    public Bitmap transform(Bitmap source) {
        int size = Math.min(source.getWidth(), source.getHeight());

    int x = (source.getWidth() - size) / 2;
    int y = (source.getHeight() - size) / 2;

    Bitmap squaredBitmap = Bitmap.createBitmap(source, x, y, size, size);
    if (squaredBitmap != source) {
        source.recycle();
    }

    Bitmap bitmap = Bitmap.createBitmap(size, size, source.getConfig());

    Canvas canvas = new Canvas(bitmap);
    Paint paint = new Paint();
    BitmapShader shader = new BitmapShader(squaredBitmap,
            BitmapShader.TileMode.CLAMP, BitmapShader.TileMode.CLAMP);
    paint.setShader(shader);
    paint.setAntiAlias(true);

    float r = size / 2f;
    canvas.drawCircle(r, r, r, paint);

    squaredBitmap.recycle();
    return bitmap;
    }

    @Override
    public String key() {
        return "circle";
    }
}

现在要应用此转换，您可以像这样使用 picasso

Picasso.with(getContext())
    .load(url)
    .transform(new MyTransform())
    .into(imageView, new com.squareup.picasso.Callback() {
                        @Override
                        public void onSuccess() {
                              // do something if its loaded successfully
                        }

                        @Override
                        public void onError() {
                             // do something if its not loaded successfully
                        }
                    });

Picasso自定义位图变换方法

Custom bitmap transformation method with Picasso

android

bitmap

picasso