鸿蒙软总线跨设备访问该怎么玩——小总结
目录：
重点撸代码：
1、跨设备启动FA、跨设备迁移、回迁
（1）权限
ohos.permission.DISTRIBUTED_DEVICE_STATE_CHANGE：用于允许监听分布式组网内的设备状态变化。 ohos.permission.GET_DISTRIBUTED_DEVICE_INFO：用于允许获取分布式组网内的设备列表和设备信息。 ohos.permission.GET_BUNDLE_INFO：用于查询其他应用的信息。 ohos.permission.DISTRIBUTED_DATASYNC：用于允许不同设备间的数据交换。 "reqPermissions": [ {"name": "ohos.permission.DISTRIBUTED_DATASYNC"}, {"name": "ohos.permission.DISTRIBUTED_DEVICE_STATE_CHANGE"}, {"name": "ohos.permission.GET_DISTRIBUTED_DEVICE_INFO" }, {"name": "ohos.permission.GET_BUNDLE_INFO"} ] //主动申明，要多设备协同，让用户选择允许还是禁止 requestPermissionsFromUser(new String[]{"ohos.permission.DISTRIBUTED_DATASYNC"}, 0);
（2）界面：ability_main.xml
<?xml version="1.0" encoding="utf-8"?> <DirectionalLayout xmlns:ohos="http://schemas.huawei.com/res/ohos" ohos:height="match_parent" ohos:width="match_parent" ohos:orientation="vertical"> <Button ohos:id="$+id:main_start_fa_btn" ohos:height="match_content" ohos:width="300vp" ohos:text="1.启动远程设备的FA" ohos:text_size="20fp" ohos:text_color="#ffffff" ohos:background_element="$graphic:button_bg" ohos:layout_alignment="horizontal_center" ohos:top_padding="8vp" ohos:bottom_padding="8vp" ohos:left_padding="40vp" ohos:right_padding="40vp" ohos:top_margin="20vp" /> <Button ohos:id="$+id:main_migration_btn" ohos:height="match_content" ohos:width="300vp" ohos:text="2.迁移到远程设备" ohos:text_size="20fp" ohos:text_color="#ffffff" ohos:background_element="$graphic:button_bg" ohos:layout_alignment="horizontal_center" ohos:top_padding="8vp" ohos:bottom_padding="8vp" ohos:left_padding="40vp" ohos:right_padding="40vp" ohos:top_margin="20vp" /> </DirectionalLayout>
button_bg.xml
<?xml version="1.0" encoding="utf-8"?> <shape xmlns:ohos="http://schemas.huawei.com/res/ohos" ohos:shape="rectangle"> <solid ohos:color="#007DFF"/> <corners ohos:radius="40"/> </shape>
另外我们需要的Page Abiltiy：MigrationAbility、RemoveAbility
MainAbilitySlice:
public class MainAbilitySlice extends AbilitySlice { private Button mainStartFABtn,mainMigrationBtn; @Override public void onStart(Intent intent) { super.onStart(intent); super.setUIContent(ResourceTable.Layout_ability_main); mainStartFABtn = (Button)findComponentById(ResourceTable.Id_main_start_fa_btn); mainMigrationBtn = (Button)findComponentById(ResourceTable.Id_main_migration_btn); mainStartFABtn.setClickedListener(mClickListener); mainMigrationBtn.setClickedListener(mClickListener); } private Component.ClickedListener mClickListener = new Component.ClickedListener() { @Override public void onClick(Component component) { int compoentId = component.getId(); switch (compoentId){ case ResourceTable.Id_main_start_fa_btn: //点击后跨设备打开Fa //第一种写法 Intent intent = new Intent(); Operation op = new Intent.OperationBuilder() .withDeviceId(Common.getOnLineDeviceId()) .withBundleName("com.ybzy.demo") .withAbilityName("com.ybzy.demo.RemoveAbility") .withFlags(Intent.FLAG_ABILITYSLICE_MULTI_DEVICE) .build(); intent.setOperation(op); intent.setParam("msg","我夸设备把你这个FA拉起来了！"); startAbility(intent); //第二钟写法 intent.setElement(new ElementName(Common.getOnLineDeviceId() ,"com.ybzy.demo","com.ybzy.demo.RemoveAbility")); intent.setFlags(Intent.FLAG_ABILITYSLICE_MULTI_DEVICE); intent.setParam("msg","我夸设备把你这个FA拉起来了！"); startAbility(intent); break; case ResourceTable.Id_main_migration_btn: //点击后进入要迁移的Ability页面 Intent migrationIntent = new Intent(); migrationIntent.setElement(new ElementName("","com.ybzy.demo" ,"com.ybzy.demo.MigrationAbility")); startAbility(migrationIntent); break; default: break; } } }; @Override public void onActive() { super.onActive(); } @Override public void onForeground(Intent intent) { super.onForeground(intent); } }
ability_migration.xml
<?xml version="1.0" encoding="utf-8"?> <DirectionalLayout xmlns:ohos="http://schemas.huawei.com/res/ohos" ohos:height="match_parent" ohos:width="match_parent" ohos:background_element="#00ffff" ohos:orientation="vertical"> <Text ohos:id="$+id:migration_text" ohos:height="match_content" ohos:width="250vp" ohos:background_element="#0088bb" ohos:layout_alignment="horizontal_center" ohos:text="下面是一个可编辑的文本框" ohos:text_size="50" ohos:padding="5vp" ohos:top_margin="30vp" /> <TextField ohos:id="$+id:migration_textfield" ohos:height="250vp" ohos:width="250vp" ohos:hint="请输入..." ohos:layout_alignment="horizontal_center" ohos:background_element="#ffffff" ohos:text_color="#888888" ohos:text_size="20fp" ohos:padding="5vp" /> <Button ohos:id="$+id:migration_migration_btn" ohos:height="match_content" ohos:width="match_content" ohos:text="点击迁移" ohos:text_size="20fp" ohos:text_color="#ffffff" ohos:background_element="$graphic:button_bg" ohos:top_padding="8vp" ohos:bottom_padding="8vp" ohos:left_padding="50vp" ohos:right_padding="50vp" ohos:layout_alignment="horizontal_center" ohos:top_margin="30vp" /> <Button ohos:id="$+id:migration_migration_back_btn" ohos:height="match_content" ohos:width="match_content" ohos:text="点击迁移回来" ohos:text_size="20fp" ohos:text_color="#ffffff" ohos:background_element="$graphic:button_bg" ohos:top_padding="8vp" ohos:bottom_padding="8vp" ohos:left_padding="50vp" ohos:right_padding="50vp" ohos:layout_alignment="horizontal_center" ohos:top_margin="30vp" /> </DirectionalLayout>
RemoveAbility...把接收到的值显示到页面就行，setText()
（3）工具类
public class Common{ public static String getDeviceId(){ List<DeviceInfo> deviceList = DeviceManager.getDeviceList(DeviceInfo.FLAG_GET_ONLINE_DEVICE); if(deviceList.isEmpty()){ return null; } int deviceNum = deviceList.size(); List<String> deviceIds = new ArrayList<>(deviceNum); List<String> deviceNames = new ArrayList<>(deviceNum); deviceList.forEach((device)->{ deviceIds.add(device.getDeviceId()); deviceNames.add(device.getDeviceName()); }); //我们这里的实验环境，就两部手机，组件还没讲 //我就直接使用deviceIds的第一个元素，做为启动远程设备的目标id String devcieIdStr = deviceIds.get(0); return devcieIdStr; } public static void myShowTip(Context context,String msg){ //提示框的核心组件文本 Text text = new Text(context); text.setWidth(MATCH_CONTENT); text.setHeight(MATCH_CONTENT); text.setTextSize(16, Text.TextSizeType.FP); text.setText(msg); text.setPadding(30,20,30,20); text.setMultipleLine(true); text.setMarginLeft(30); text.setMarginRight(30); text.setTextColor(Color.WHITE); text.setTextAlignment(TextAlignment.CENTER); //给上面的文本设置一个背景样式 ShapeElement style = new ShapeElement(); style.setShape(ShapeElement.RECTANGLE); style.setRgbColor(new RgbColor(77,77,77)); style.setCornerRadius(15); text.setBackground(style); //构建存放上面的text的布局 DirectionalLayout mainLayout = new DirectionalLayout(context); mainLayout.setWidth(MATCH_PARENT); mainLayout.setHeight(MATCH_CONTENT); mainLayout.setAlignment(LayoutAlignment.CENTER); mainLayout.addComponent(text); //最后要让上面的组件绑定dialog ToastDialog toastDialog = new ToastDialog(context); toastDialog.setSize(MATCH_PARENT,MATCH_CONTENT); toastDialog.setDuration(1500); toastDialog.setAutoClosable(true); toastDialog.setTransparent(true); toastDialog.setAlignment(LayoutAlignment.CENTER); toastDialog.setComponent((Component) mainLayout); toastDialog.show(); } }
（4）实现功能
MigrationAbilitySlice：
public class MigrationAbilitySlice extends AbilitySlice implements IAbilityContinuation { TextField migrationTextField; Button migrationMigrationBtn,migrationMigrationBackBtn; String msg = ""; @Override public void onStart(Intent intent) { super.onStart(intent); super.setUIContent(ResourceTable.Layout_ability_migration); migrationTextField = (TextField)findComponentById(ResourceTable.Id_migration_textfield); migrationTextField.setText(msg); migrationMigrationBtn = (Button)findComponentById(ResourceTable.Id_migration_migration_btn); migrationMigrationBtn.setClickedListener(component -> { //1、要进行迁移的Ability实现接口 IAbilityContinuation，实现的方法返回值改成true //2、要进行迁移的Ability下面关联的所有AbilitySlice都要实现接口 IAbilityContinuation， // 实现的方法上处理数据 //3、进行迁移 String deviceId = Common.getOnLineDeviceId(); if(deviceId != null){ // continueAbility(deviceId); continueAbilityReversibly(deviceId); } }); migrationMigrationBackBtn = (Button) findComponentById(ResourceTable .Id_migration_migration_back_btn); migrationMigrationBackBtn.setClickedListener(component -> { reverseContinueAbility(); }); } @Override public void onActive() { super.onActive(); } @Override public void onForeground(Intent intent) { super.onForeground(intent); } @Override public boolean onStartContinuation() { return true; } @Override public boolean onSaveData(IntentParams intentParams) { intentParams.setParam("msg",migrationTextField.getText()); return true; } @Override public boolean onRestoreData(IntentParams intentParams) { msg = intentParams.getParam("msg").toString(); // getUITaskDispatcher().asyncDispatch(() -> { // migrationTextField.setText(intentParams.getParam("msg").toString()); // }); return true; } @Override public void onCompleteContinuation(int i) { } }
2、跨设备连接Service
启动远程设备Service的代码示例如下：
添加按钮：
<Button ohos:id="$+id:main_start_removeService_btn" ohos:height="match_content" ohos:width="300vp" ohos:text="远程启动ServiceAbility" ohos:text_size="20fp" ohos:text_color="#ffffff" ohos:background_element="$graphic:button_bg" ohos:layout_alignment="horizontal_center" ohos:top_padding="8vp" ohos:bottom_padding="8vp" ohos:left_padding="40vp" ohos:right_padding="40vp" ohos:top_margin="20vp" /> <Button ohos:id="$+id:main_stop_removeService_btn" ohos:height="match_content" ohos:width="300vp" ohos:text="远程关闭ServiceAbility" ohos:text_size="20fp" ohos:text_color="#ffffff" ohos:background_element="$graphic:button_bg" ohos:layout_alignment="horizontal_center" ohos:top_padding="8vp" ohos:bottom_padding="8vp" ohos:left_padding="40vp" ohos:right_padding="40vp" ohos:top_margin="20vp" />
新建RemoteServiceAbility：
public class RemoteServiceAbility extends Ability { private static final HiLogLabel LABEL_LOG = new HiLogLabel(3, 0xD001100, "Demo"); private Source sVideoSource; private Player sPlayer; @Override public void onStart(Intent intent) { HiLog.error(LABEL_LOG, "RmoteServiceAbility::onStart"); super.onStart(intent); Common.myShowTip(this,"remote onstart"); sPlayer = new Player(RemoteServiceAbility.this); new PlayerThread().start(); } class PlayerThread extends Thread { @Override public void run() { try { File mp3FilePath = getExternalFilesDir(Environment.DIRECTORY_MUSIC); if (!mp3FilePath.exists()) { mp3FilePath.mkdirs(); } File mp3File = new File(mp3FilePath.getAbsolutePath() + "/" + "bj.mp3"); Resource res = getResourceManager() .getRawFileEntry("resources/rawfile/bj.mp3").openRawFile(); byte[] buf = new byte[4096]; int count = 0; FileOutputStream fos = new FileOutputStream(mp3File); while ((count = res.read(buf)) != -1) { fos.write(buf, 0, count); } FileDescriptor fileDescriptor = new FileInputStream(mp3File).getFD(); sVideoSource = new Source(fileDescriptor); sPlayer.setSource(sVideoSource); sPlayer.prepare(); sPlayer.setVolume(0.3f); sPlayer.enableSingleLooping(true); sPlayer.play(); } catch (IOException e) { e.printStackTrace(); } } } @Override public void onStop() { super.onStop(); Common.myShowTip(RemoteServiceAbility.this,"remote onStop"); sPlayer.stop(); } @Override public IRemoteObject onConnect(Intent intent) { return null; } @Override public void onDisconnect(Intent intent) { } }
启动：
case ResourceTable.Id_main_start_remoteService_btn: Common.myShowTip(MainAbilitySlice.this,deviceId); Intent startRemoteServiceIntent = new Intent(); startRemoteServiceIntent.setElement(new ElementName( deviceId, "com.ybzy.demo", "com.ybzy.demo.RemoteServiceAbility" )); startRemoteServiceIntent.setFlags(Intent.FLAG_ABILITYSLICE_MULTI_DEVICE); startAbility(startRemoteServiceIntent); break;
关闭远程设备Service：
case ResourceTable.Id_main_stop_remoteService_btn: Common.myShowTip(MainAbilitySlice.this,deviceId); Intent stopRemoteServiceIntent = new Intent(); stopRemoteServiceIntent.setElement(new ElementName( deviceId, "com.ybzy.demo", "com.ybzy.demo.RemoteServiceAbility" )); stopRemoteServiceIntent.setFlags(Intent.FLAG_ABILITYSLICE_MULTI_DEVICE); stopAbility(stopRemoteServiceIntent); break;
仅通过启动和停止Service Ability两种方式对Service进行调度无法应对需长期交互的场景，
简单地说，信息就是只能去，回不来！
因此，分布式任务调度平台向开发者提供了跨设备Service连接及断开连接的能力。
链接上了，信息可去可回！
链接是使用connectAbility()方法，需要传入目标Service的Intent与接口IAbilityConnection的实例对象。
接口IAbilityConnection提供了两个方法供开发者实现：
（1）onAbilityConnectDone()用来处理连接的回调。
（2）onAbilityDisconnectDone()用来处理断开连接的回调。
我们可以在onAbilityConnectDone()中获取管理链接的代理，进一步为了使用该代理跨设备调度Service，
开发者需要在本地及远端分别实现对外接口一致的代理，这个接口是IRemoteBroker。
添加按钮：
<Button ohos:id="$+id:main_connect_remoteService_btn" ohos:height="match_content" ohos:width="300vp" ohos:text="远程链接ServiceAbility" ohos:text_size="20fp" ohos:text_color="#ffffff" ohos:background_element="$graphic:button_bg" ohos:layout_alignment="horizontal_center" ohos:top_padding="8vp" ohos:bottom_padding="8vp" ohos:left_padding="40vp" ohos:right_padding="40vp" ohos:top_margin="20vp" /> <Button ohos:id="$+id:main_use_remoteService_btn" ohos:height="match_content" ohos:width="300vp" ohos:text="使用远程ServiceAbility" ohos:text_size="20fp" ohos:text_color="#ffffff" ohos:background_element="$graphic:button_bg" ohos:layout_alignment="horizontal_center" ohos:top_padding="8vp" ohos:bottom_padding="8vp" ohos:left_padding="40vp" ohos:right_padding="40vp" ohos:top_margin="20vp" /> <Button ohos:id="$+id:main_disconnect_remoteService_btn" ohos:height="match_content" ohos:width="300vp" ohos:text="远程断开ServiceAbility" ohos:text_size="20fp" ohos:text_color="#ffffff" ohos:background_element="$graphic:button_bg" ohos:layout_alignment="horizontal_center" ohos:top_padding="8vp" ohos:bottom_padding="8vp" ohos:left_padding="40vp" ohos:right_padding="40vp" ohos:top_margin="20vp" />
发起连接的本地侧的代理示例如下：
public class MyRemoteProxy implements IRemoteBroker { //IRemoteBroker:获取远程代理对象的持有者 private static final int ERR_OK = 0; //COMMAND_PLUS表示有效消息进行通信的约定的标记，MIN_TRANSACTION_ID是这个标记可以用的最小值：1 private static final int COMMAND_PLUS = IRemoteObject.MIN_TRANSACTION_ID; //IRemoteObject:此接口 // 可用于查询或获取接口描述符、 // 添加或删除死亡通知、 // 将对象状态转储到特定文件以及发送消息。 private final IRemoteObject remote; public MyRemoteProxy(IRemoteObject remote) { this.remote = remote; } @Override public IRemoteObject asObject() {//获取远程代理对象的方法 return remote; } public int plus(int a,int b) throws RemoteException { //MessageParcel:这个类提供了读写对象、接口标记、文件描述符和大数据的方法。 MessageParcel data = MessageParcel.obtain(); //obtain()创建索引为0的空MessageParcel对象 MessageParcel reply = MessageParcel.obtain(); //MessageOption:定义与sendRequest一起发送消息的选项。 // option不同的取值，决定采用同步或异步方式跨设备调用Service // 这个例子我们需要同步获取对端Service执行加法运算后的结果，同步模式调用sendRequest接口，即MessageOption.TF_SYNC // 对应的是异步：TF_ASYNC MessageOption option = new MessageOption(MessageOption.TF_SYNC); data.writeInt(a); data.writeInt(b); try { remote.sendRequest(COMMAND_PLUS, data, reply, option); //第1个参数：约定通信双方确定的消息标记。 //第2个参数：发送到对等端侧的数据包裹MessageParcel对象。 //第3个参数：对等端侧返回的数据包裹MessageParcel对象。 //第4个参数：设置发送消息，用同步还是异步模式。 int ec = reply.readInt(); //返回通信成不成功，约定的标记ERR_OK if (ec != ERR_OK) { throw new RemoteException(); } int result = reply.readInt(); return result; } catch (RemoteException e) { throw new RemoteException(); } finally { data.reclaim(); //reclaim()清除不再使用的MessageParcel对象。 reply.reclaim(); } } }
等待连接的远端侧的代理示例如下：
public class MyRemote extends RemoteObject implements IRemoteBroker{ private static final int ERR_OK = 0; private static final int ERROR = -1; private static final int COMMAND_PLUS = IRemoteObject.MIN_TRANSACTION_ID; public MyRemote() { super("MyService_Remote"); } @Override public IRemoteObject asObject() { return this; } @Override public boolean onRemoteRequest(int code, MessageParcel data, MessageParcel reply, MessageOption option) { if (code != COMMAND_PLUS) { reply.writeInt(ERROR); return false; } int value1 = data.readInt(); int value2 = data.readInt(); int sum = value1 + value2; reply.writeInt(ERR_OK); reply.writeInt(sum); return true; } }
等待连接侧还需要作如下修改：
// 绑定前面定义的代理，实例化出发起链接侧需要的代理 private MyRemote remote = new MyRemote(); @Override public IRemoteObject onConnect(Intent intent) { //链接成功的时候，给发起链接侧返回去 return remote.asObject(); }
完成上述步骤后，可以通过点击事件实现连接、利用连接关系控制PA以及断开连接等行为，代码示例如下：
private MyRemoteProxy mProxy = null; // 创建连接回调实例 private IAbilityConnection conn = new IAbilityConnection() { // 连接到Service的回调 @Override public void onAbilityConnectDone(ElementName elementName, IRemoteObject iRemoteObject, int resultCode) { // 在这里开发者可以拿到服务端传过来IRemoteObject对象，从中解析出服务端传过来的信息 mProxy = new MyRemoteProxy(iRemoteObject); UIUtils.showTip(MainAbilitySlice.this,"拿到remoteObject：" + mProxy); } // 意外断开连接才会回调 @Override public void onAbilityDisconnectDone(ElementName elementName, int resultCode) { } }; // 连接远程 case ResourceTable.Id_main_connect_remoteService_btn: //1、实现连接的本地侧的代理 //2、实现等待连接的远端侧的代理 //3、修改等待连接侧的Service //4、在本地(发起链接侧)获取远端(被链接侧)返回过来的链接代理，创建链接后的回调函数 //5、实现链接，通过代理对象使用Service的服务 if (deviceId != null) { Intent connectServiceIntent = new Intent(); connectServiceIntent.setElement(new ElementName( deviceId, "com.ybzy.demo", "com.ybzy.demo.RemoteServiceAbility" )); connectServiceIntent.setFlags(Intent.FLAG_ABILITYSLICE_MULTI_DEVICE); connectAbility(connectServiceIntent, iAbilityConnection); } break; // 链接后使用 case ResourceTable.Id_main_use_remoteService_btn: if (mProxy != null) { int ret = -1; try { ret = mProxy.plus(10, 20); } catch (RemoteException e) { e.printStackTrace(); } Common.myShowTip(MainAbilitySlice.this, "获取的结果：" + ret); } break; // 用完断开 case ResourceTable.Id_main_disconnect_remoteService_btn: disconnectAbility(iAbilityConnection); break;
作者：zhonghongfa
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