Java tutorial
/* * Copyright (C) 2015 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.android.builder.png; import static com.google.common.base.Preconditions.checkArgument; import static com.google.common.base.Preconditions.checkState; import com.android.annotations.NonNull; import com.android.ide.common.res2.ResourcePreprocessor; import com.android.ide.common.resources.configuration.DensityQualifier; import com.android.ide.common.resources.configuration.FolderConfiguration; import com.android.ide.common.resources.configuration.VersionQualifier; import com.android.ide.common.vectordrawable.VdPreview; import com.android.resources.Density; import com.android.resources.ResourceFolderType; import com.android.utils.ILogger; import com.google.common.base.Charsets; import com.google.common.collect.Lists; import com.google.common.io.Files; import org.w3c.dom.Document; import org.w3c.dom.Element; import java.awt.image.BufferedImage; import java.io.File; import java.io.IOException; import java.util.Collection; import javax.imageio.ImageIO; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; /** * Generates PNG images (and XML copies) from VectorDrawable files. */ @SuppressWarnings("MethodMayBeStatic") public class VectorDrawableRenderer implements ResourcePreprocessor { /** Projects with minSdk set to this or higher don't need to generate PNGs. */ public static final int MIN_SDK_WITH_VECTOR_SUPPORT = 21; private final ILogger mLogger; private final File mOutputDir; private final Collection<Density> mDensities; public VectorDrawableRenderer(File outputDir, Collection<Density> densities, ILogger logger) { mOutputDir = outputDir; mDensities = densities; mLogger = logger; } public Collection<File> createPngFiles(@NonNull File inputXmlFile, @NonNull File outputResDirectory, @NonNull Collection<Density> densities) throws IOException { throw new RuntimeException("Replaced by the new way to generate PNGs"); } @Override public boolean needsPreprocessing(File resourceFile) { return isXml(resourceFile) && isInDrawable(resourceFile) && getEffectiveVersion(resourceFile) < MIN_SDK_WITH_VECTOR_SUPPORT && isRootVector(resourceFile); } @Override public Collection<File> getFilesToBeGenerated(File inputXmlFile) { FolderConfiguration originalConfiguration = getFolderConfiguration(inputXmlFile); // Create all the PNG files and duplicate the XML into folders with the version qualifier. Collection<File> filesToBeGenerated = Lists.newArrayList(); for (Density density : mDensities) { FolderConfiguration newConfiguration = FolderConfiguration.copyOf(originalConfiguration); newConfiguration.setDensityQualifier(new DensityQualifier(density)); File directory = new File(mOutputDir, newConfiguration.getFolderName(ResourceFolderType.DRAWABLE)); File pngFile = new File(directory, inputXmlFile.getName().replace(".xml", ".png")); filesToBeGenerated.add(pngFile); newConfiguration.setVersionQualifier(new VersionQualifier(MIN_SDK_WITH_VECTOR_SUPPORT)); File destination = new File(mOutputDir, newConfiguration.getFolderName(ResourceFolderType.DRAWABLE)); File xmlCopy = new File(destination, inputXmlFile.getName()); filesToBeGenerated.add(xmlCopy); } return filesToBeGenerated; } @Override public void generateFile(File toBeGenerated, File original) throws IOException { Files.createParentDirs(toBeGenerated); if (isXml(toBeGenerated)) { Files.copy(original, toBeGenerated); } else { mLogger.info("Generating PNG: [%s] from [%s]", toBeGenerated.getAbsolutePath(), original.getAbsolutePath()); FolderConfiguration folderConfiguration = getFolderConfiguration(toBeGenerated); checkState(folderConfiguration.getDensityQualifier() != null); Density density = folderConfiguration.getDensityQualifier().getValue(); String xmlContent = Files.toString(original, Charsets.UTF_8); float scaleFactor = density.getDpiValue() / (float) Density.MEDIUM.getDpiValue(); if (scaleFactor <= 0) { scaleFactor = 1.0f; } final VdPreview.TargetSize imageSize = VdPreview.TargetSize.createSizeFromScale(scaleFactor); BufferedImage image = VdPreview.getPreviewFromVectorXml(imageSize, xmlContent, null); checkState(image != null, "Generating the image failed."); ImageIO.write(image, "png", toBeGenerated); } } @NonNull private FolderConfiguration getFolderConfiguration(@NonNull File inputXmlFile) { String parentName = inputXmlFile.getParentFile().getName(); FolderConfiguration originalConfiguration = FolderConfiguration.getConfigForFolder(parentName); checkArgument(originalConfiguration != null, "Invalid resource folder name [%s].", parentName); return originalConfiguration; } private boolean isInDrawable(@NonNull File inputXmlFile) { ResourceFolderType folderType = ResourceFolderType.getFolderType(inputXmlFile.getParentFile().getName()); return folderType == ResourceFolderType.DRAWABLE; } /** * Parse the root element of the file, return true if it is a vector. * TODO: Combine this with the drawing code, such that we don't parse the file twice. */ private boolean isRootVector(File resourceFile) { DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance(); boolean result = false; try { DocumentBuilder dBuilder = dbFactory.newDocumentBuilder(); Document doc = dBuilder.parse(resourceFile); Element root = doc.getDocumentElement(); if (root != null && root.getNodeName().equalsIgnoreCase("vector")) { result = true; } } catch (Exception e) { mLogger.error(e, "Exception in parsing the XML resource" + e.getMessage()); } return result; } private boolean isXml(File resourceFile) { return resourceFile.getPath().endsWith(".xml"); } private int getEffectiveVersion(File resourceFile) { FolderConfiguration configuration = getFolderConfiguration(resourceFile); if (configuration.getVersionQualifier() == null) { configuration.createDefault(); } //noinspection ConstantConditions - handled above. return configuration.getVersionQualifier().getVersion(); } }