1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.databinding.tool.expr; 18 19 import android.databinding.tool.reflection.ModelAnalyzer; 20 import android.databinding.tool.reflection.ModelClass; 21 import android.databinding.tool.writer.KCode; 22 23 import java.util.List; 24 25 /** 26 * This is a special expression that is created when we have an adapter that has multiple 27 * parameters. 28 * <p> 29 * When it is detected, we create a new binding with this argument list expression and merge N 30 * bindings into a new one so that rest of the code generation logic works as expected. 31 */ 32 public class ArgListExpr extends Expr { 33 private int mId; 34 public ArgListExpr(int id, Iterable<Expr> children) { 35 super(children); 36 mId = id; 37 } 38 39 @Override 40 protected String computeUniqueKey() { 41 return "ArgList[" + mId + "]" + super.computeUniqueKey(); 42 } 43 44 @Override 45 protected KCode generateCode(boolean expand) { 46 throw new IllegalStateException("should never try to convert an argument expressions" 47 + " into code"); 48 } 49 50 @Override 51 protected ModelClass resolveType(ModelAnalyzer modelAnalyzer) { 52 return modelAnalyzer.findClass(Void.class); 53 } 54 55 @Override 56 protected List<Dependency> constructDependencies() { 57 return super.constructDynamicChildrenDependencies(); 58 } 59 60 @Override 61 public boolean canBeEvaluatedToAVariable() { 62 return false; 63 } 64 65 @Override 66 public String getInvertibleError() { 67 return "Merged bindings are not invertible."; 68 } 69 } 70