1 /* 2 * Copyright (C) 2010 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 com.android.camera; 18 19 import android.content.Context; 20 import android.util.AttributeSet; 21 import android.util.Xml; 22 import android.view.InflateException; 23 24 import org.xmlpull.v1.XmlPullParser; 25 import org.xmlpull.v1.XmlPullParserException; 26 27 import java.io.IOException; 28 import java.lang.reflect.Constructor; 29 import java.util.ArrayList; 30 import java.util.HashMap; 31 32 /** 33 * Inflate <code>CameraPreference</code> from XML resource. 34 */ 35 public class PreferenceInflater { 36 private static final String PACKAGE_NAME = 37 PreferenceInflater.class.getPackage().getName(); 38 39 private static final Class<?>[] CTOR_SIGNATURE = 40 new Class[] {Context.class, AttributeSet.class}; 41 private static final HashMap<String, Constructor<?>> sConstructorMap = 42 new HashMap<String, Constructor<?>>(); 43 44 private Context mContext; 45 46 public PreferenceInflater(Context context) { 47 mContext = context; 48 } 49 50 public CameraPreference inflate(int resId) { 51 return inflate(mContext.getResources().getXml(resId)); 52 } 53 54 private CameraPreference newPreference(String tagName, Object[] args) { 55 String name = PACKAGE_NAME + "." + tagName; 56 Constructor<?> constructor = sConstructorMap.get(name); 57 try { 58 if (constructor == null) { 59 // Class not found in the cache, see if it's real, and try to 60 // add it 61 Class<?> clazz = mContext.getClassLoader().loadClass(name); 62 constructor = clazz.getConstructor(CTOR_SIGNATURE); 63 sConstructorMap.put(name, constructor); 64 } 65 return (CameraPreference) constructor.newInstance(args); 66 } catch (NoSuchMethodException e) { 67 throw new InflateException("Error inflating class " + name, e); 68 } catch (ClassNotFoundException e) { 69 throw new InflateException("No such class: " + name, e); 70 } catch (Exception e) { 71 throw new InflateException("While create instance of" + name, e); 72 } 73 } 74 75 private CameraPreference inflate(XmlPullParser parser) { 76 77 AttributeSet attrs = Xml.asAttributeSet(parser); 78 ArrayList<CameraPreference> list = new ArrayList<CameraPreference>(); 79 Object args[] = new Object[]{mContext, attrs}; 80 81 try { 82 for (int type = parser.next(); 83 type != XmlPullParser.END_DOCUMENT; type = parser.next()) { 84 if (type != XmlPullParser.START_TAG) continue; 85 CameraPreference pref = newPreference(parser.getName(), args); 86 87 int depth = parser.getDepth(); 88 if (depth > list.size()) { 89 list.add(pref); 90 } else { 91 list.set(depth - 1, pref); 92 } 93 if (depth > 1) { 94 ((PreferenceGroup) list.get(depth - 2)).addChild(pref); 95 } 96 } 97 98 if (list.size() == 0) { 99 throw new InflateException("No root element found"); 100 } 101 return list.get(0); 102 } catch (XmlPullParserException e) { 103 throw new InflateException(e); 104 } catch (IOException e) { 105 throw new InflateException(parser.getPositionDescription(), e); 106 } 107 } 108 } 109