/**
* Looks through filtered drawables for files not of the target density and replaces them with
* scaled versions.
*
* <p>Any drawables found by this step didn't have equivalents in the target density. If they are
* of a higher density, we can replicate what Android does and downscale them at compile-time.
*/
private void scaleUnmatchedDrawables(ExecutionContext context)
throws IOException, InterruptedException {
ResourceFilters.Density targetDensity = ResourceFilters.Density.ORDERING.max(targetDensities);
// Go over all the images that remain after filtering.
Preconditions.checkNotNull(drawableFinder);
Collection<Path> drawables =
drawableFinder.findDrawables(inResDirToOutResDirMap.values(), filesystem);
for (Path drawable : drawables) {
if (drawable.toString().endsWith(".9.png")) {
// Skip nine-patch for now.
continue;
}
ResourceFilters.Qualifiers qualifiers = new ResourceFilters.Qualifiers(drawable);
ResourceFilters.Density density = qualifiers.density;
// If the image has a qualifier but it's not the right one.
Preconditions.checkNotNull(targetDensities);
if (!targetDensities.contains(density)) {
// Replace density qualifier with target density using regular expression to match
// the qualifier in the context of a path to a drawable.
String fromDensity =
(density == ResourceFilters.Density.NO_QUALIFIER ? "" : "-") + density.toString();
Path destination =
Paths.get(
MorePaths.pathWithUnixSeparators(drawable)
.replaceFirst(
"((?:^|/)drawable[^/]*)" + Pattern.quote(fromDensity) + "(-|$|/)",
"$1-" + targetDensity + "$2"));
double factor = targetDensity.value() / density.value();
if (factor >= 1.0) {
// There is no point in up-scaling, or converting between drawable and drawable-mdpi.
continue;
}
// Make sure destination folder exists and perform downscaling.
filesystem.createParentDirs(destination);
Preconditions.checkNotNull(imageScaler);
imageScaler.scale(factor, drawable, destination, context);
// Delete source file.
filesystem.deleteFileAtPath(drawable);
// Delete newly-empty directories to prevent missing resources errors in apkbuilder.
Path parent = drawable.getParent();
if (filesystem.listFiles(parent).length == 0) {
filesystem.deleteFileAtPath(parent);
}
}
}
}
public ResourceFilter(List<String> resourceFilter) {
this.filter = ImmutableSet.copyOf(resourceFilter);
this.densities = Sets.newHashSet();
boolean downscale = false;
for (String component : filter) {
if ("downscale".equals(component)) {
downscale = true;
} else {
densities.add(ResourceFilters.Density.from(component));
}
}
this.downscale = downscale;
}
