Java tutorial
/* * Copyright (C) 2012 The Android Open Source Project * * Licensed under the Eclipse Public License, Version 1.0 (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.eclipse.org/org/documents/epl-v10.php * * 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.ide.eclipse.adt.internal.project; import static com.android.ide.common.layout.LayoutConstants.FQCN_GRID_LAYOUT; import static com.android.ide.common.layout.LayoutConstants.FQCN_GRID_LAYOUT_V7; import static com.android.ide.common.layout.LayoutConstants.FQCN_SPACE; import static com.android.ide.common.layout.LayoutConstants.FQCN_SPACE_V7; import com.android.annotations.NonNull; import com.android.annotations.Nullable; import com.android.ide.eclipse.adt.AdtUtils; import com.android.ide.eclipse.adt.internal.actions.AddCompatibilityJarAction; import com.android.ide.eclipse.adt.internal.editors.manifest.ManifestInfo; import com.android.ide.eclipse.adt.internal.sdk.ProjectState; import com.android.ide.eclipse.adt.internal.sdk.ProjectState.LibraryState; import com.android.ide.eclipse.adt.internal.sdk.Sdk; import org.eclipse.core.resources.IProject; import org.eclipse.jdt.core.IJavaProject; import org.eclipse.jface.dialogs.MessageDialog; import org.eclipse.swt.widgets.Display; /** * Helper class for the Android Support Library. The support library provides * (for example) a backport of GridLayout, which must be used as a library * project rather than a jar library since it has resources. This class provides * support for finding the library project, or downloading and installing it on * demand if it does not, as well as translating tags such as * {@code <GridLayout>} into {@code <com.android.support.v7.GridLayout>} if it * does not. */ public class CompatibilityLibraryHelper { /** * Returns the correct tag to use for the given view tag. This is normally * the same as the tag itself. However, for some views which are not available * on all platforms, this will: * <ul> * <li> Check if the view is available in the compatibility library, * and if so, if the support library is not installed, will offer to * install it via the SDK manager. * <li> (The tool may also offer to adjust the minimum SDK of the project * up to a level such that the given tag is supported directly, and then * this method will return the original tag.) * <li> Check whether the compatibility library is included in the project, and * if not, offer to copy it into the workspace and add a library dependency. * <li> Return the alternative tag. For example, for "GridLayout", it will * (if the minimum SDK is less than 14) return "com.android.support.v7.GridLayout" * instead. * </ul> * * @param project the project to add the dependency into * @param tag the tag to look up, such as "GridLayout" * @return the tag to use in the layout, normally the same as the input tag but possibly * an equivalent compatibility library tag instead. */ @NonNull public static String getTagFor(@NonNull IProject project, @NonNull String tag) { boolean isGridLayout = tag.equals(FQCN_GRID_LAYOUT); boolean isSpace = tag.equals(FQCN_SPACE); if (isGridLayout || isSpace) { int minSdk = ManifestInfo.get(project).getMinSdkVersion(); if (minSdk < 14) { // See if the support library is installed in the SDK area // See if there is a local project in the workspace providing the // project IProject supportProject = getSupportProjectV7(); if (supportProject != null) { // Make sure I have a dependency on it ProjectState state = Sdk.getProjectState(project); if (state != null) { for (LibraryState library : state.getLibraries()) { if (supportProject.equals(library.getProjectState().getProject())) { // Found it: you have the compatibility library and have linked // to it: use the alternative tag return isGridLayout ? FQCN_GRID_LAYOUT_V7 : FQCN_SPACE_V7; } } } } // Ask user to install it String message = String.format("%1$s requires API level 14 or higher, or a compatibility " + "library for older versions.\n\n" + " Do you want to install the compatibility library?", tag); MessageDialog dialog = new MessageDialog(Display.getCurrent().getActiveShell(), "Warning", null, message, MessageDialog.QUESTION, new String[] { "Install", "Cancel" }, 1 /* default button: Cancel */); int answer = dialog.open(); if (answer == 0) { if (supportProject != null) { // Just add library dependency if (!AddCompatibilityJarAction.addLibraryDependency(supportProject, project, true /* waitForFinish */)) { return tag; } } else { // Install library AND add dependency if (!AddCompatibilityJarAction.installLibrary(project, true /* waitForFinish */)) { return tag; } } return isGridLayout ? FQCN_GRID_LAYOUT_V7 : FQCN_SPACE_V7; } } } return tag; } /** Cache for {@link #getSupportProjectV7()} */ private static IProject sCachedProject; /** * Finds and returns the support project in the workspace, if any. * * @return the android support library project, or null if not found */ @Nullable public static IProject getSupportProjectV7() { if (sCachedProject != null) { if (sCachedProject.isAccessible()) { return sCachedProject; } else { sCachedProject = null; } } sCachedProject = findSupportProjectV7(); return sCachedProject; } @Nullable private static IProject findSupportProjectV7() { for (IJavaProject javaProject : AdtUtils.getOpenAndroidProjects()) { IProject project = javaProject.getProject(); ProjectState state = Sdk.getProjectState(project); if (state.isLibrary()) { ManifestInfo manifestInfo = ManifestInfo.get(project); if (manifestInfo.getPackage().equals("android.support.v7.gridlayout")) { //$NON-NLS-1$ return project; } } } return null; } }