本文目錄

功能4：數據庫映射

xUtils3簡介

xUtils 包含了orm, http(s), image, view註解, 但依然很輕量級(251K), 並且特性強大, 方便擴展.
官網：https://github.com/wyouflf/xUtils3

xUtils使用方法

使用前準備

第一步：引入

implementation 'org.xutils:xutils:3.8.5'

第二步：添加權限

<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

AndroidManifest.xml文件application 節點裏添加

android:requestLegacyExternalStorage="true"
android:usesCleartextTraffic="true"

第三步：MainActivity中添加

x.Ext.init(getApplication());
x.Ext.setDebug(BuildConfig.DEBUG);// 是否輸出debug日誌, 開啓debug會影響性能.
x.view().inject(this);//沒有用到view註解可以先不用

功能1：訪問網絡

不帶參數的網絡請求

不帶緩存

RequestParams params = new RequestParams("http://baidu.com");
x.http().get(params, new Callback.CommonCallback<String>() {
    @Override
    public void onSuccess(String result) {
        
    }

    @Override
    public void onError(Throwable ex, boolean isOnCallback) {

    }

    @Override
    public void onCancelled(CancelledException cex) {

    }

    @Override
    public void onFinished() {

    }
});

帶緩存

RequestParams params = new RequestParams("http://baidu.com");
x.http().get(params, new Callback.CacheCallback<String>() {
    @Override
    public boolean onCache(String result) {
        return false;
    }

    @Override
    public void onSuccess(String result) {
        Log.i("MainActivity", result);
  
    }

    @Override
    public void onError(Throwable ex, boolean isOnCallback) {
        Log.i("MainActivity", ex.getMessage());
    }

    @Override
    public void onCancelled(CancelledException cex) {

    }

    @Override
    public void onFinished() {

    }
});

帶參數的請求

RequestParams params = new RequestParams("https://www.baidu.com/s");
    // params.setSslSocketFactory(...); // 如果需要自定義SSL
params.addQueryStringParameter("wd", "xUtils");

功能2：加載網絡圖片

ImageOptions imageOptions;
imageOptions = new ImageOptions.Builder()
                .setSize(DensityUtil.dip2px(120), DensityUtil.dip2px(120))
                .setRadius(DensityUtil.dip2px(5))
                // 如果ImageView的大小不是定義爲wrap_content, 不要crop.
                .setCrop(true) // 很多時候設置了合適的scaleType也不需要它.
                // 加載中或錯誤圖片的ScaleType
                //.setPlaceholderScaleType(ImageView.ScaleType.MATRIX)
                .setImageScaleType(ImageView.ScaleType.CENTER_CROP)
                .setLoadingDrawableId(R.mipmap.ic_launcher)
                .setFailureDrawableId(R.mipmap.ic_launcher)
                .build();

// 加載網絡圖片
x.image().bind(imageView, url, imageOptions);

// 加載本地assets目錄的圖片
x.image().bind(imageView, "assets://test.gif", imageOptions);

// resources file
x.image().bind(imageView, "res://" + R.minimap.test, imageOptions);

// local file
x.image().bind(imageView, new File("/sdcard/test.gif").toURI().toString(), imageOptions);
x.image().bind(imageView, "/sdcard/test.gif", imageOptions);
x.image().bind(imageView, "file:///sdcard/test.gif", imageOptions);
x.image().bind(imageView, "file:/sdcard/test.gif", imageOptions);

x.image().bind(imageView, url, imageOptions, new Callback.CommonCallback<Drawable>() {...});
x.image().loadDrawable(url, imageOptions, new Callback.CommonCallback<Drawable>() {...});
// 用來獲取緩存文件
x.image().loadFile(url, imageOptions, new Callback.CommonCallback<File>() {...});

功能3：框架註解

佈局文件註解

//替代onCreate方法中的    setContentView(R.layout.activity_main);
@ContentView(R.layout.activity_main)
public class MainActivity extends AppCompatActivity {
}

控件註解

@ViewInject(R.id.textView)
private TextView mTextView;

點擊事件註解

單個點擊事件

/**
 * 1. 方法必須私有限定,
 * 2. 方法參數形式必須和type對應的Listener接口一致.
 * 3. 註解參數value支持數組: value={id1, id2, id3}
 * 4. 其它參數說明見{@link org.xutils.event.annotation.Event}類的說明.
 **/
@Event(value = R.id.btn_test1,
        type = View.OnClickListener.class/*可選參數, 默認是View.OnClickListener.class*/)
private void onTest1Click(View view) {
	...
}

多個點擊事件

@Event(value = {R.id.button,R.id.button2},
        type = View.OnClickListener.class/*可選參數, 默認是View.OnClickListener.class*/)
private void onTest1Click(View view) {
 switch (view.getId()){
     case R.id.button:
            Log.i("MainActivity", "button1 click");
        break;
        case R.id.button2:
            Log.i("MainActivity", "button2 click");
            break;
    }
}

功能4：數據庫映射

下面以單表爲例演示xUtils框架怎麼對數據庫進行增刪改查操作
首先添加一個實體類，在實體類上加一個註解

package com.hnu.sqlite.db;

import org.xutils.db.annotation.Column;
import org.xutils.db.annotation.Table;

@Table(name = "user")
public class User {
    @Column(name = "id", isId = true)
    private int id;
    @Column(name = "username")
    private String username;

    @Column(name = "password")
    private String password;

    @Column(name = "age")
    private int age;


    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", username='" + username + '\'' +
                ", password='" + password + '\'' +
                ", age=" + age +
                '}';
    }
}

在對數據庫操作前，先創建DaoConfig 對象

    DbManager.DaoConfig daoConfig = new DbManager.DaoConfig()
            .setDbName("test.db")
            // 不設置dbDir時, 默認存儲在app的私有目錄.
	// .setDbDir(new File("/sdcard")) // "sdcard"的寫法並非最佳實踐, 這裏爲了簡單, 先這樣寫了.
            .setDbVersion(2)
            .setDbOpenListener(new DbManager.DbOpenListener() {
                @Override
                public void onDbOpened(DbManager db) {
                    // 開啓WAL, 對寫入加速提升巨大
                    db.getDatabase().enableWriteAheadLogging();
                }
            })
            .setDbUpgradeListener(new DbManager.DbUpgradeListener() {
                @Override
                public void onUpgrade(DbManager db, int oldVersion, int newVersion) {
                    // TODO: ...
                    // db.addColumn(...);
                    // db.dropTable(...);
                    // ...
                    // or
                    // db.dropDb();
                }
            });

增加數據

 DbManager db = null;
 try {
     db = x.getDb(daoConfig);
     User user = new User();
     user.setUsername("test"+System.currentTimeMillis());
     user.setPassword("passwd");
     user.setAge(30);
     db.save(user);
 } catch (DbException e) {
     e.printStackTrace();
     return;
 }

刪除數據

根據id 刪除

DbManager db = null;
try {
    db = x.getDb(daoConfig);
    User user = new User();
    user.setId(2);
    db.delete(user);
} catch (DbException e) {
    e.printStackTrace();
    return;
}

根據條件刪除

DbManager db = null;
try {  
    db = x.getDb(daoConfig);
    db.delete(User.class,
            WhereBuilder.b("username", "=", "test"));

} catch (DbException e) {
    e.printStackTrace();
    return;
}

修改數據

根據id修改

try { 
     DbManager db = null;
     db = x.getDb(daoConfig);
     User user = new User();
     user.setId(1);
     user.setUsername("new user");
     user.setPassword("new passwd");
     user.setAge(30);
     db.saveOrUpdate(user);
    // db.update(user);或者用這個方法修改
 } catch (DbException e) {
     e.printStackTrace();
     return;
 }

根據條件修改

try {  
	DbManager db = null;
	db = x.getDb(daoConfig);
	db.update(User.class, WhereBuilder.b("username", "=", "test"),
// WhereBuilder.b("id", "=", 1).and("isAdmin", "=", true).,
   new KeyValue("username", "test_name"), new KeyValue("password", "new pss"));
} catch (DbException e) {
	e.printStackTrace();
	return;
}

查詢數據

DbManager db = null;
try {// 刪除1
    db = x.getDb(daoConfig);
    List<User> users = new ArrayList<>();
    users= db.selector(User.class).orderBy("id", true).limit(1000).where("username","=","test").findAll();
// users= db.selector(User.class).orderBy("id", true).limit(1000).findAll();
// users= db.selector(User.class).findAll();
    for (User user : users){
        Log.i("testdb","test" + user);
    }

} catch (DbException e) {
    e.printStackTrace();
    return;
}

Android xUtils框架最全使用詳解