| /* |
| * 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 com.android.SdkConstants; |
| import com.android.annotations.NonNull; |
| import com.android.annotations.Nullable; |
| import com.android.tools.lint.client.api.JavaEvaluator; |
| 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.SourceCodeScanner; |
| import com.intellij.psi.PsiAnonymousClass; |
| import com.intellij.psi.PsiMethod; |
| import com.intellij.psi.PsiParameter; |
| import com.intellij.psi.PsiParameterList; |
| import com.intellij.psi.PsiType; |
| import java.util.Collections; |
| import java.util.List; |
| import org.jetbrains.uast.UClass; |
| |
| /** Looks for custom views that do not define the view constructors needed by UI builders */ |
| public class ViewConstructorDetector extends Detector implements SourceCodeScanner { |
| /** The main issue discovered by this detector */ |
| public static final Issue ISSUE = |
| Issue.create( |
| "ViewConstructor", |
| "Missing View constructors for XML inflation", |
| "Some layout tools (such as the Android layout editor) need 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)) |
| .setAndroidSpecific(true); |
| |
| /** Constructs a new {@link ViewConstructorDetector} check */ |
| public ViewConstructorDetector() {} |
| |
| // ---- implements SourceCodeScanner ---- |
| |
| private static boolean isXmlConstructor( |
| @NonNull JavaEvaluator evaluator, @NonNull PsiMethod method) { |
| // Accept |
| // android.content.Context |
| // android.content.Context,android.util.AttributeSet |
| // android.content.Context,android.util.AttributeSet,int |
| PsiParameterList parameterList = method.getParameterList(); |
| int argumentCount = parameterList.getParametersCount(); |
| if (argumentCount == 0 || argumentCount > 3) { |
| return false; |
| } |
| PsiParameter[] parameters = parameterList.getParameters(); |
| if (!evaluator.typeMatches(parameters[0].getType(), CLASS_CONTEXT)) { |
| return false; |
| } |
| if (argumentCount == 1) { |
| return true; |
| } |
| if (!evaluator.typeMatches(parameters[1].getType(), CLASS_ATTRIBUTE_SET)) { |
| return false; |
| } |
| //noinspection SimplifiableIfStatement |
| if (argumentCount == 2) { |
| return true; |
| } |
| return PsiType.INT.equals(parameters[2].getType()); |
| } |
| |
| @Nullable |
| @Override |
| public List<String> applicableSuperClasses() { |
| return Collections.singletonList(SdkConstants.CLASS_VIEW); |
| } |
| |
| @Override |
| public void visitClass(@NonNull JavaContext context, @NonNull UClass declaration) { |
| // Only applies to concrete classes |
| JavaEvaluator evaluator = context.getEvaluator(); |
| if (evaluator.isAbstract(declaration) |
| || evaluator.isPrivate(declaration) |
| || declaration instanceof PsiAnonymousClass) { |
| // Ignore abstract, private and anonymous classes |
| return; |
| } |
| |
| if (declaration.getContainingClass() != null && !evaluator.isStatic(declaration)) { |
| // 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 (PsiMethod constructor : declaration.getConstructors()) { |
| if (isXmlConstructor(evaluator, 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)`", |
| declaration.getName()); |
| Location location = context.getNameLocation(declaration); |
| context.report(ISSUE, declaration, location, message); |
| } |
| } |
| } |