GreenDao初体验——GreenDao与Android最新版本兼容性问题

GreenDao以前也玩过，但是由于项目原因，一直没用到，今天，想拿来玩玩，至于GreenDao具体怎么使用，我就不说了，在这里推荐一篇博客：GreenDao基础使用，先说一下我今天遇到的问题吧，我是安装这篇博客的流程来练习GreenDao的用法的，但是在中途突然之间就抛出了一个问题，我们先来瞧瞧是什么问题吧：

12-02 02:40:29.385 9554-9554/com.morse.greendaodemo E/AndroidRuntime﹕ FATAL EXCEPTION: main java.lang.RuntimeException: Unable to start activity ComponentInfo{com.morse.greendaodemo/com.morse.greendaodemo.MainActivity}: android.content.res.Resources$NotFoundException: File res/drawable/abc_vector_test.xml from drawable resource ID #0x7f020052 at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084) at android.app.ActivityThread.access$600(ActivityThread.java:130) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:4745) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:511) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) at dalvik.system.NativeStart.main(Native Method) Caused by: android.content.res.Resources$NotFoundException: File res/drawable/abc_vector_test.xml from drawable resource ID #0x7f020052 at android.content.res.Resources.loadDrawable(Resources.java:1918) at android.content.res.Resources.getDrawable(Resources.java:659) at android.support.v4.content.ContextCompat.getDrawable(ContextCompat.java:374) at android.support.v7.widget.AppCompatDrawableManager.getDrawable(AppCompatDrawableManager.java:200) at android.support.v7.widget.AppCompatDrawableManager.getDrawable(AppCompatDrawableManager.java:188) at android.support.v7.widget.AppCompatDrawableManager.checkVectorDrawableSetup(AppCompatDrawableManager.java:723) at android.support.v7.widget.AppCompatDrawableManager.getDrawable(AppCompatDrawableManager.java:193) at android.support.v7.widget.TintTypedArray.getDrawableIfKnown(TintTypedArray.java:81) at android.support.v7.app.AppCompatDelegateImplBase.<init>(AppCompatDelegateImplBase.java:127) at android.support.v7.app.AppCompatDelegateImplV9.<init>(AppCompatDelegateImplV9.java:147) at android.support.v7.app.AppCompatDelegateImplV11.<init>(AppCompatDelegateImplV11.java:27) at android.support.v7.app.AppCompatDelegateImplV14.<init>(AppCompatDelegateImplV14.java:53) at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:205) at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:185) at android.support.v7.app.AppCompatActivity.getDelegate(AppCompatActivity.java:525) at android.support.v7.app.AppCompatActivity.onCreate(AppCompatActivity.java:74) at com.morse.greendaodemo.MainActivity.onCreate(MainActivity.java:13) at android.app.Activity.performCreate(Activity.java:5008) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084) at android.app.ActivityThread.access$600(ActivityThread.java:130) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:4745) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:511) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) at dalvik.system.NativeStart.main(Native Method) Caused by: org.xmlpull.v1.XmlPullParserException: Binary XML file line #17: invalid drawable tag vector at android.graphics.drawable.Drawable.createFromXmlInner(Drawable.java:877) at android.graphics.drawable.Drawable.createFromXml(Drawable.java:818) at android.content.res.Resources.loadDrawable(Resources.java:1915) at android.content.res.Resources.getDrawable(Resources.java:659) at android.support.v4.content.ContextCompat.getDrawable(ContextCompat.java:374) at android.support.v7.widget.AppCompatDrawableManager.getDrawable(AppCompatDrawableManager.java:200) at android.support.v7.widget.AppCompatDrawableManager.getDrawable(AppCompatDrawableManager.java:188) at android.support.v7.widget.AppCompatDrawableManager.checkVectorDrawableSetup(AppCompatDrawableManager.java:723) at android.support.v7.widget.AppCompatDrawableManager.getDrawable(AppCompatDrawableManager.java:193) at android.support.v7.widget.TintTypedArray.getDrawableIfKnown(TintTypedArray.java:81) at android.support.v7.app.AppCompatDelegateImplBase.<init>(AppCompatDelegateImplBase.java:127) at android.support.v7.app.AppCompatDelegateImplV9.<init>(AppCompatDelegateImplV9.java:147) at android.support.v7.app.AppCompatDelegateImplV11.<init>(AppCompatDelegateImplV11.java:27) at android.support.v7.app.AppCompatDelegateImplV14.<init>(AppCompatDelegateImplV14.java:53) at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:205) at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:185) at android.support.v7.app.AppCompatActivity.getDelegate(AppCompatActivity.java:525) at android.support.v7.app.AppCompatActivity.onCreate(AppCompatActivity.java:74) at com.morse.greendaodemo.MainActivity.onCreate(MainActivity.java:13) at android.app.Activity.performCreate(Activity.java:5008) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084) at android.app.ActivityThread.access$600(ActivityThread.java:130) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195) at android.os.Handler.dispatchMessage(Handler.java:99) at android.os.Looper.loop(Looper.java:137) at android.app.ActivityThread.main(ActivityThread.java:4745) at java.lang.reflect.Method.invokeNative(Native Method) at java.lang.reflect.Method.invoke(Method.java:511) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) at dalvik.system.NativeStart.main(Native Method)

看上去像是xml解析的问题，嘿嘿，如果你是这么想，那么你就错了。不扯了，之间上代码： MainActivity：

public class MainActivity extends AppCompatActivity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); DBManager dbManager = DBManager.getInstance(this); for (int i = 0; i < 5; i++) { User user = new User(); user.setId(i); user.setAge(i * 3); user.setName("第" + i + "人"); dbManager.insertUser(user); } List<User> userList = dbManager.queryUserList(); for (User user : userList) { Log.e("TAG", "queryUserList--before-->" + user.getId() + "--" + user.getName() + "--" + user.getAge()); if (user.getId() == 0) { dbManager.deleteUser(user); } if (user.getId() == 3) { user.setAge(10); dbManager.updateUser(user); } } userList = dbManager.queryUserList(); for (User user : userList) { Log.e("TAG", "queryUserList--after--->" + user.getId() + "---" + user.getName()+"--"+user.getAge()); } } }

MyApplication ：

public class MyApplication extends Application { private DaoMaster.DevOpenHelper mHelper; private SQLiteDatabase db; private DaoMaster mDaoMaster; private DaoSession mDaoSession; public static MyApplication instances; @Override public void onCreate() { super.onCreate(); instances = this; setDatabase(); } public static MyApplication getInstances(){ return instances; } /** * 设置greenDao */ private void setDatabase() { // 通过 DaoMaster 的内部类 DevOpenHelper，你可以得到一个便利的 SQLiteOpenHelper 对象。 // 可能你已经注意到了，你并不需要去编写「CREATE TABLE」这样的 SQL 语句，因为 greenDAO 已经帮你做了。 // 注意：默认的 DaoMaster.DevOpenHelper 会在数据库升级时，删除所有的表，意味着这将导致数据的丢失。 // 所以，在正式的项目中，你还应该做一层封装，来实现数据库的安全升级。 mHelper = new DaoMaster.DevOpenHelper(this, "notes-db", null); db = mHelper.getWritableDatabase(); // 注意：该数据库连接属于 DaoMaster，所以多个 Session 指的是相同的数据库连接。 mDaoMaster = new DaoMaster(db); mDaoSession = mDaoMaster.newSession(); } public DaoSession getDaoSession() { return mDaoSession; } public SQLiteDatabase getDb() { return db; } }

DBManager：

public class DBManager { private final static String dbName = "test_db"; private static DBManager mInstance; private DaoMaster.DevOpenHelper openHelper; private Context context; public DBManager(Context context) { this.context = context; openHelper = new DaoMaster.DevOpenHelper(context, dbName, null); } /** * 获取单例引用 * * @param context * @return */ public static DBManager getInstance(Context context) { if (mInstance == null) { synchronized (DBManager.class) { if (mInstance == null) { mInstance = new DBManager(context); } } } return mInstance; } /** * 获取可读数据库 */ private SQLiteDatabase getReadableDatabase() { if (openHelper == null) { openHelper = new DaoMaster.DevOpenHelper(context, dbName, null); } SQLiteDatabase db = openHelper.getReadableDatabase(); return db; } /** * 获取可写数据库 */ private SQLiteDatabase getWritableDatabase() { if (openHelper == null) { openHelper = new DaoMaster.DevOpenHelper(context, dbName, null); } SQLiteDatabase db = openHelper.getWritableDatabase(); return db; } /** * 插入一条记录 * * @param user */ public void insertUser(User user) { DaoMaster daoMaster = new DaoMaster(getWritableDatabase()); DaoSession daoSession = daoMaster.newSession(); UserDao userDao = daoSession.getUserDao(); userDao.insert(user); } /** * 插入用户集合 * * @param users */ public void insertUserList(List<User> users) { if (users == null || users.isEmpty()) { return; } DaoMaster daoMaster = new DaoMaster(getWritableDatabase()); DaoSession daoSession = daoMaster.newSession(); UserDao userDao = daoSession.getUserDao(); userDao.insertInTx(users); } /** * 删除一条记录 * * @param user */ public void deleteUser(User user) { DaoMaster daoMaster = new DaoMaster(getWritableDatabase()); DaoSession daoSession = daoMaster.newSession(); UserDao userDao = daoSession.getUserDao(); userDao.delete(user); } /** * 更新一条记录 * * @param user */ public void updateUser(User user) { DaoMaster daoMaster = new DaoMaster(getWritableDatabase()); DaoSession daoSession = daoMaster.newSession(); UserDao userDao = daoSession.getUserDao(); userDao.update(user); } /** * 查询用户列表 */ public List<User> queryUserList() { DaoMaster daoMaster = new DaoMaster(getReadableDatabase()); DaoSession daoSession = daoMaster.newSession(); UserDao userDao = daoSession.getUserDao(); QueryBuilder<User> qb = userDao.queryBuilder(); List<User> list = qb.list(); return list; } /** * 查询用户列表 */ public List<User> queryUserList(int age) { DaoMaster daoMaster = new DaoMaster(getReadableDatabase()); DaoSession daoSession = daoMaster.newSession(); UserDao userDao = daoSession.getUserDao(); QueryBuilder<User> qb = userDao.queryBuilder(); qb.where(UserDao.Properties.Age.gt(age)).orderAsc(UserDao.Properties.Age); List<User> list = qb.list(); return list; } }

User：

@Entity public class User { @Id private long id; private String name; private int age; @Generated(hash = 446251977) public User(long id, String name, int age) { this.id = id; this.name = name; this.age = age; } @Generated(hash = 586692638) public User() { } public long getId() { return id; } public void setId(long id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } }

最后上一个布局文件：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" tools:context=".MainActivity"> <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="@string/hello_world"/> </RelativeLayout>

没错，代码就这么多，根本就没有用到数据解析。那究竟是什么问题呢？大胆假设一下，有什么东西可以让一个框架失去本身的价值呢？除了google，应该没有谁了吧。 经过我的假设，事实确实如此，看一下我的gradle.build吧：

App:

apply plugin: 'com.android.application' apply plugin: 'org.greenrobot.greendao' android { compileSdkVersion 25 buildToolsVersion "25.0.1" defaultConfig { applicationId "com.morse.greendaodemo" minSdkVersion 15 targetSdkVersion 25 versionCode 1 versionName "1.0" } buildTypes { release { minifyEnabled false proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro' } } } greendao { schemaVersion 1 daoPackage 'com.morse.greendao.gen' targetGenDir 'src/main/java' } dependencies { compile fileTree(include: ['*.jar'], dir: 'libs') compile 'com.android.support:appcompat-v7:25.0.1' compile 'org.greenrobot:greendao-generator:3.2.0' compile 'org.greenrobot:greendao:3.2.0' }

主项目：

buildscript { repositories { jcenter() } dependencies { classpath 'com.android.tools.build:gradle:1.3.0' classpath 'org.greenrobot:greendao-gradle-plugin:3.2.0' // NOTE: Do not place your application dependencies here; they belong // in the individual module build.gradle files } } allprojects { repositories { jcenter() } }

可以看到，我目前使用的是最新的api版本，或许是因为GreenDao版本太低，或许是Api版本太高，至于是哪个问题，看看就知道，GreenDao的版本是最新的，应该不会出问题，那看看Api版本，我的做法是降低Api的版本，修改如下：

android { compileSdkVersion 23 buildToolsVersion "23.0.1" defaultConfig { applicationId "com.morse.greendaodemo" minSdkVersion 15 targetSdkVersion 23 versionCode 1 versionName "1.0" } buildTypes { release { minifyEnabled false proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro' } } }

编译，运行，好吧，竟然成功运行了，看来还真是api新版本与GreenDao的兼容性问题。

到这里，我的问题已经解决了，你们的呢？

如果你觉得这篇博客对你有帮助，欢迎踩一下。