| /* |
| * Copyright (C) 2012 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.tools.lint.checks; |
| |
| import static com.android.SdkConstants.CLASS_ATTRIBUTE_SET; |
| import static com.android.SdkConstants.CLASS_CONTEXT; |
| import static com.android.tools.lint.client.api.JavaParser.ResolvedClass; |
| import static com.android.tools.lint.client.api.JavaParser.ResolvedMethod; |
| |
| import com.android.SdkConstants; |
| import com.android.annotations.NonNull; |
| import com.android.annotations.Nullable; |
| import com.android.tools.lint.detector.api.Category; |
| import com.android.tools.lint.detector.api.Detector; |
| import com.android.tools.lint.detector.api.Implementation; |
| import com.android.tools.lint.detector.api.Issue; |
| import com.android.tools.lint.detector.api.JavaContext; |
| import com.android.tools.lint.detector.api.Location; |
| import com.android.tools.lint.detector.api.Scope; |
| import com.android.tools.lint.detector.api.Severity; |
| import com.android.tools.lint.detector.api.Speed; |
| |
| import java.lang.reflect.Modifier; |
| import java.util.Collections; |
| import java.util.List; |
| |
| import lombok.ast.ClassDeclaration; |
| import lombok.ast.Node; |
| import lombok.ast.NormalTypeBody; |
| |
| /** |
| * Looks for custom views that do not define the view constructors needed by UI builders |
| */ |
| public class ViewConstructorDetector extends Detector implements Detector.JavaScanner { |
| /** The main issue discovered by this detector */ |
| public static final Issue ISSUE = Issue.create( |
| "ViewConstructor", //$NON-NLS-1$ |
| "Missing View constructors for XML inflation", |
| |
| "Some layout tools (such as the Android layout editor for Studio & Eclipse) needs to " + |
| "find a constructor with one of the following signatures:\n" + |
| "* `View(Context context)`\n" + |
| "* `View(Context context, AttributeSet attrs)`\n" + |
| "* `View(Context context, AttributeSet attrs, int defStyle)`\n" + |
| "\n" + |
| "If your custom view needs to perform initialization which does not apply when " + |
| "used in a layout editor, you can surround the given code with a check to " + |
| "see if `View#isInEditMode()` is false, since that method will return `false` " + |
| "at runtime but true within a user interface editor.", |
| |
| Category.USABILITY, |
| 3, |
| Severity.WARNING, |
| new Implementation( |
| ViewConstructorDetector.class, |
| Scope.JAVA_FILE_SCOPE)); |
| |
| /** Constructs a new {@link ViewConstructorDetector} check */ |
| public ViewConstructorDetector() { |
| } |
| |
| @NonNull |
| @Override |
| public Speed getSpeed() { |
| return Speed.FAST; |
| } |
| |
| // ---- Implements JavaScanner ---- |
| |
| private static boolean isXmlConstructor(ResolvedMethod method) { |
| // Accept |
| // android.content.Context |
| // android.content.Context,android.util.AttributeSet |
| // android.content.Context,android.util.AttributeSet,int |
| int argumentCount = method.getArgumentCount(); |
| if (argumentCount == 0 || argumentCount > 3) { |
| return false; |
| } |
| if (!method.getArgumentType(0).matchesName(CLASS_CONTEXT)) { |
| return false; |
| } |
| if (argumentCount == 1) { |
| return true; |
| } |
| if (!method.getArgumentType(1).matchesName(CLASS_ATTRIBUTE_SET)) { |
| return false; |
| } |
| //noinspection SimplifiableIfStatement |
| if (argumentCount == 2) { |
| return true; |
| } |
| return method.getArgumentType(2).matchesName("int"); |
| } |
| |
| @Nullable |
| @Override |
| public List<String> applicableSuperClasses() { |
| return Collections.singletonList(SdkConstants.CLASS_VIEW); |
| } |
| |
| @Override |
| public void checkClass(@NonNull JavaContext context, @Nullable ClassDeclaration node, |
| @NonNull Node declarationOrAnonymous, @NonNull ResolvedClass resolvedClass) { |
| if (node == null) { |
| return; |
| } |
| |
| // Only applies to concrete classes |
| int flags = node.astModifiers().getEffectiveModifierFlags(); |
| // Ignore abstract classes |
| if ((flags & Modifier.ABSTRACT) != 0) { |
| return; |
| } |
| |
| if (node.getParent() instanceof NormalTypeBody |
| && ((flags & Modifier.STATIC) == 0)) { |
| // Ignore inner classes that aren't static: we can't create these |
| // anyway since we'd need the outer instance |
| return; |
| } |
| |
| boolean found = false; |
| for (ResolvedMethod constructor : resolvedClass.getConstructors()) { |
| if (isXmlConstructor(constructor)) { |
| found = true; |
| break; |
| } |
| } |
| |
| if (!found) { |
| String message = String.format( |
| "Custom view `%1$s` is missing constructor used by tools: " |
| + "`(Context)` or `(Context,AttributeSet)` " |
| + "or `(Context,AttributeSet,int)`", |
| node.astName().astValue()); |
| Location location = context.getLocation(node.astName()); |
| context.report(ISSUE, node, location, message /*data*/); |
| } |
| } |
| } |