src/plugins/android.codeutils/src/com/motorola/studio/android/generateviewbylayout/codegenerators/FindViewByIdCodeGenerator.java

/*
 * 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.motorola.studio.android.generateviewbylayout.codegenerators;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.SubMonitor;
import org.eclipse.jdt.core.JavaModelException;
import org.eclipse.jdt.core.dom.MethodDeclaration;
import org.eclipse.jdt.core.dom.MethodInvocation;
import org.eclipse.jdt.core.dom.SimpleName;
import org.eclipse.jdt.core.dom.TypeDeclaration;

import com.motorola.studio.android.codeutils.i18n.CodeUtilsNLS;
import com.motorola.studio.android.common.IAndroidConstants;
import com.motorola.studio.android.common.utilities.AndroidUtils;
import com.motorola.studio.android.generatecode.JDTUtils;
import com.motorola.studio.android.generateviewbylayout.JavaViewBasedOnLayoutModifierConstants;
import com.motorola.studio.android.generateviewbylayout.model.CodeGeneratorDataBasedOnLayout;
import com.motorola.studio.android.generateviewbylayout.model.LayoutNode;

/**
 * Responsible to create findViewById statements
 */
public class FindViewByIdCodeGenerator extends AbstractLayoutCodeGenerator
{

    protected IFile javaFile;

    /**
     * @param codeGeneratorData
     * @param onCreateDeclaration
     * @param typeDeclaration
     * @param javaFile file used to get API version number (it is necessary to differentiate between Activity or Fragment in the findViewById method invocation)
     */
    public FindViewByIdCodeGenerator(CodeGeneratorDataBasedOnLayout codeGeneratorData,
            MethodDeclaration onCreateDeclaration, TypeDeclaration typeDeclaration, IFile javaFile)
    {
        super(codeGeneratorData, onCreateDeclaration, typeDeclaration);
        this.javaFile = javaFile;
    }

    @Override
    public void generateCode(IProgressMonitor monitor) throws JavaModelException
    {
        addFindByIdStatement(monitor);
    }

    /**
     * Field Assigment to find item inside layout xml 
     * 
     * <br>
     * GENERATED_CODE_FORMAT:
     * <br>
     * $GUI_ID = $GUI_TYPE findViewById(R.id.$GUI_ID);
     */
    private void addFindByIdStatement(IProgressMonitor monitor) throws JavaModelException
    {
        SubMonitor subMonitor = SubMonitor.convert(monitor);
        subMonitor.beginTask(CodeUtilsNLS.JavaViewBasedOnLayoutModifier_AddingFindingViewById,
                codeGeneratorData.getGuiItems().size());
        /* AST To be written 
         * ExpressionStatement
        Assignment
                leftHand        SimpleName(button1)     
                Assignment.Operator =
                rightHand       CastExpression
                                expression MethodInvocation
                                    arguments = QualifiedName(R.id.button1)
                                    SimpleName = findViewById
                                type 
                                    SimpleType (Button)
        */

        for (LayoutNode node : codeGeneratorData.getGuiItems())
        {
            if ((node.getNodeId() != null) && node.shouldInsertCode())
            {
                boolean containsFindViewByIdDeclaration = checkIfFindViewByIdAlreadyDeclared(node);
                if (!containsFindViewByIdDeclaration)
                {
                    //avoid to call method twice
                    if (!node.isFragmentPlaceholder())
                    {
                        //not fragment                                                        
                        addAssignmentStatement(node, null,
                                JavaViewBasedOnLayoutModifierConstants.FIND_VIEW_BY_ID);
                    }
                    else
                    {
                        //is fragment placeholder
                        MethodInvocation optionalInvocation =
                                onCreateDeclaration.getAST().newMethodInvocation();
                        String methodName = null;
                        try
                        {
                            if ((AndroidUtils.getApiVersionNumberForProject(javaFile.getProject()) < 11)
                                    && JDTUtils.isCompatibilityFragmentActivitySubclass(javaFile))
                            {
                                //if compatibility package (before 3.0)
                                methodName =
                                        JavaViewBasedOnLayoutModifierConstants.GET_SUPPORT_FRAGMENT_MANAGER;
                            }
                            else if ((AndroidUtils.getApiVersionNumberForProject(javaFile
                                    .getProject()) < IAndroidConstants.API_LEVEL_FOR_PLATFORM_VERSION_3_0_0)
                                    && !JDTUtils.isCompatibilityFragmentActivitySubclass(javaFile))
                            {
                                //if compatibility package (before 3.0)
                                //but user is trying to use compatibility package with Activity (instead of FragmentActivity)                            
                                throw new JavaModelException(
                                        new IllegalArgumentException(
                                                CodeUtilsNLS.FindViewByIdCodeGenerator_CompatibilityModeClassNeedToExtendFragmentActivityError),
                                        IStatus.ERROR);
                            }
                            else if ((AndroidUtils.getApiVersionNumberForProject(javaFile
                                    .getProject()) >= IAndroidConstants.API_LEVEL_FOR_PLATFORM_VERSION_3_0_0))
                            {
                                //if after 3.0 (API level >=11)
                                methodName =
                                        JavaViewBasedOnLayoutModifierConstants.GET_FRAGMENT_MANAGER;
                            }
                            if (methodName != null)
                            {
                                SimpleName managerMethod =
                                        onCreateDeclaration.getAST().newSimpleName(methodName);
                                optionalInvocation.setName(managerMethod);
                                addAssignmentStatement(node, optionalInvocation,
                                        JavaViewBasedOnLayoutModifierConstants.FIND_FRAGMENT_BY_ID);
                            }
                        }
                        catch (Exception e)
                        {
                            throw new JavaModelException(e, IStatus.ERROR);
                        }

                    }
                }
            }
            subMonitor.worked(1);
        }
    }
}