创建自定义转换的最佳方式,例如填充颜色:
public class BackgroundColorTransform implements Transformation {
@ColorInt int mFillColor;
public BackgroundColorTransform(@ColorInt int color) {
super();
mFillColor = color;
}
@Override
public Bitmap transform(Bitmap bitmap) {
// Create another bitmap that will hold the results of the filter.
int width = bitmap.getWidth();
int height = bitmap.getHeight();
Bitmap out = Bitmap.createBitmap(width, height, bitmap.getConfig());
Canvas canvas = new Canvas(out);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
canvas.drawColor(mFillColor);
canvas.drawBitmap(bitmap, 0f, 0f, paint);
bitmap.recycle();
return out;
}
@Override
public String key() {
return "BackgroundColorTransform:"+mFillColor;
}
}
用法:
mPicasso.load(imageUrl)
.transform(new BackgroundColorTransform(ContextCompat.getColor(getContext(),R.color.black)))
.into(mLogoImageView);
如果要添加矢量可绘制图像,请使用转换:
public class AddVectorDrawableTransform implements Transformation {
private Drawable mDrawable;
@ColorInt int mTintColor;
public AddVectorDrawableTransform(Drawable drawable, @ColorInt int tintColor) {
super();
mDrawable = drawable;
mTintColor = tintColor;
}
@Override
public Bitmap transform(Bitmap bitmap) {
// Create another bitmap that will hold the results of the filter.
int width = bitmap.getWidth();
int height = bitmap.getHeight();
Bitmap out = Bitmap.createBitmap(width, height, bitmap.getConfig());
Canvas canvas = new Canvas(out);
Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
canvas.drawBitmap(bitmap, 0f, 0f, paint);
Drawable drawable = mDrawable.mutate();
drawable = DrawableCompat.wrap(drawable);
DrawableCompat.setTint(drawable, mTintColor);
DrawableCompat.setTintMode(drawable, PorterDuff.Mode.SRC_IN);
// mDrawable.setColorFilter( mTintColor, PorterDuff.Mode.MULTIPLY);
drawable.setBounds(width/4, height/4, 3*width/4, 3*height/4);
drawable.draw(canvas);
bitmap.recycle();
return out;
}
@Override
public String key() {
return "AddDrawableTransform:"+mDrawable+", "+mTintColor;
}
}