Android通過RemoteViews實現跨進程更新UI示例

2019-12-12 03:45:54

字體：大中小

來源：轉載

供稿：網友

一、概述

前面一篇文章Android通過AIDL實現跨進程更新UI我們學習了aidl跨進程更新ui，這種傳統方式實現跨進程更新UI是可行的，但有以下弊端：

View中的方法數比較多，在IPC中需要增加對應的方法比較繁瑣。
View的每一個方法都會涉及到IPC操作，多次IPC帶來的開銷問題不容小覷。
View中方法的某些參數可能不支持IPC傳輸。例如：OnClickListener，它僅僅是個接口沒有序列化。

接下來我們通過RemoteViews實現跨進程更新UI

二、實現效果圖

在同一個應用中有兩個Activity，MainActivity和Temp2Activity，這兩個Activity不在同一個進程中。

這里寫圖片描述

現在需要通過Temp2Activity來改變MainActivity中的視圖，即在MainActivity中添加兩個Button，也就是實現跨進程更新UI這么一個功能。

在MainActivity里點擊“跳轉到新進程ACTIVITY”按鈕，會啟動一個新進程的Temp2Activity，我們先點擊“綁定服務”，這樣我們就啟動了服務，再點擊“AIDL更新”按鈕，通過調用handler來實現跨進程更新UI，點擊返回，我們發現MainActivity頁面中新添加了兩個按鈕，并且按鈕還具有點擊事件。

這里寫圖片描述

三、核心代碼

IremoteViewsManager.aidl

里面提供了兩個方法，一個是根據id更新TextView里面的內容，一個是根據id添加view視圖

// IremoteViewsManager.aidl.aidlpackage com.czhappy.remoteviewdemo;interface IremoteViewsManager {  void addRemoteView(in RemoteViews remoteViews);}

RemoteViewsAIDLService.Java

package com.czhappy.remoteviewdemo.service;import android.app.Service;import android.content.Intent;import android.os.Binder;import android.os.Bundle;import android.os.IBinder;import android.os.Message;import android.os.RemoteException;import android.widget.RemoteViews;import com.czhappy.remoteviewdemo.IremoteViewsManager;import com.czhappy.remoteviewdemo.activity.MainActivity;/** * Description: * User: chenzheng * Date: 2017/2/10 0010 * Time: 10:56 */public class RemoteViewsAIDLService extends Service {  private static final String TAG = "RemoteViewsAIDLService";  private Binder remoteViewsBinder = new IremoteViewsManager.Stub(){    @Override    public void addRemoteView(RemoteViews remoteViews) throws RemoteException {      Message message = new Message();      message.what = 1;      Bundle bundle = new Bundle();      bundle.putParcelable("remoteViews",remoteViews);      message.setData(bundle);      new MainActivity.MyHandler(RemoteViewsAIDLService.this,getMainLooper()).sendMessage(message);    }  };  public RemoteViewsAIDLService() {  }  @Override  public IBinder onBind(Intent intent) {    return remoteViewsBinder;  }}

MainActivity.java

package com.czhappy.remoteviewdemo.activity;import android.content.Context;import android.content.Intent;import android.os.Bundle;import android.os.Handler;import android.os.Looper;import android.os.Message;import android.support.v7.app.AppCompatActivity;import android.util.Log;import android.view.LayoutInflater;import android.view.View;import android.widget.LinearLayout;import android.widget.RemoteViews;import android.widget.TextView;import com.czhappy.remoteviewdemo.R;import java.lang.ref.WeakReference;public class MainActivity extends AppCompatActivity {  private static String TAG = "MainActivity";  private static LinearLayout mLinearLayout;  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    mLinearLayout = (LinearLayout) this.findViewById(R.id.mylayout);  }  public static class MyHandler extends Handler {    WeakReference<Context> weakReference;    public MyHandler(Context context, Looper looper) {      super(looper);      weakReference = new WeakReference<>(context);    }    @Override    public void handleMessage(Message msg) {      super.handleMessage(msg);      Log.i(TAG, "handleMessage");      switch (msg.what) {        case 1: //RemoteViews的AIDL實現          RemoteViews remoteViews = msg.getData().getParcelable("remoteViews");          if (remoteViews != null) {            Log.i(TAG, "updateUI");            View view = remoteViews.apply(weakReference.get(), mLinearLayout);            mLinearLayout.addView(view);          }          break;        default:          break;      }    }  };  public void readyGo(View view){    Intent intent = new Intent(MainActivity.this, Temp2Activity.class);    startActivity(intent);  }}

Temp2Activity.java

package com.czhappy.remoteviewdemo.activity;import android.app.PendingIntent;import android.content.ComponentName;import android.content.Context;import android.content.Intent;import android.content.ServiceConnection;import android.os.Bundle;import android.os.IBinder;import android.os.RemoteException;import android.support.annotation.Nullable;import android.support.v7.app.AppCompatActivity;import android.util.Log;import android.view.View;import android.widget.RemoteViews;import com.czhappy.remoteviewdemo.IremoteViewsManager;import com.czhappy.remoteviewdemo.R;import com.czhappy.remoteviewdemo.service.RemoteViewsAIDLService;/** * Description: * User: chenzheng * Date: 2017/2/9 0009 * Time: 16:05 */public class Temp2Activity extends AppCompatActivity {  private String TAG = "Temp2Activity";  private IremoteViewsManager remoteViewsManager;  private boolean isBind = false;  private ServiceConnection remoteViewServiceConnection = new ServiceConnection() {    @Override    public void onServiceConnected(ComponentName name, IBinder service) {      Log.i(TAG,"onServiceConnected");      remoteViewsManager = IremoteViewsManager.Stub.asInterface(service);    }    @Override    public void onServiceDisconnected(ComponentName name) {      //回收      remoteViewsManager = null;    }  };  @Override  protected void onCreate(@Nullable Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    this.setContentView(R.layout.activity_temp);  }  /**   * 綁定服務   */  public void bindService(View view) {    Intent viewServiceIntent = new Intent(this,RemoteViewsAIDLService.class);    isBind = bindService(viewServiceIntent,remoteViewServiceConnection, Context.BIND_AUTO_CREATE);  }  /**   * 更新UI   */  public void UpdateUI(View view){    RemoteViews remoteViews = new RemoteViews(Temp2Activity.this.getPackageName(),R.layout.button_layout);    Intent intentClick = new Intent(Temp2Activity.this,FirstActivity.class);    PendingIntent openFirstActivity = PendingIntent.getActivity(Temp2Activity.this,0,intentClick,0);    remoteViews.setOnClickPendingIntent(R.id.firstButton,openFirstActivity);    Intent secondClick = new Intent(Temp2Activity.this,SecondActivity.class);    PendingIntent openSecondActivity = PendingIntent.getActivity(Temp2Activity.this,0,secondClick,0);    remoteViews.setOnClickPendingIntent(R.id.secondButton,openSecondActivity);    remoteViews.setCharSequence(R.id.secondButton,"setText","想改就改");    try {      remoteViewsManager.addRemoteView(remoteViews);    } catch (RemoteException e) {      e.printStackTrace();    }  }  @Override  protected void onDestroy() {    super.onDestroy();    if(isBind){      unbindService(remoteViewServiceConnection);      isBind = false;    }  }}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"  package="com.czhappy.remoteviewdemo">  <application    android:allowBackup="true"    android:icon="@mipmap/ic_launcher"    android:label="@string/app_name"    android:supportsRtl="true"    android:theme="@style/AppTheme">    <activity android:name=".activity.MainActivity">      <intent-filter>        <action android:name="android.intent.action.MAIN" />        <category android:name="android.intent.category.LAUNCHER" />      </intent-filter>    </activity>    <activity android:name=".activity.FirstActivity" />    <activity android:name=".activity.SecondActivity" />    <activity      android:name=".activity.Temp2Activity"      android:process=":remote2" />    <service android:name="com.czhappy.remoteviewdemo.service.RemoteViewsAIDLService" />  </application></manifest>

四、總結

RemoteViews就是為跨進程更新UI而生的，內部封裝了很多方法用來實現跨進程更新UI。但這并不代表RemoteViews是就是萬能的了，它也有不足之處，目前支持的布局和View有限

layout：

FrameLayout LinearLayout RelativeLayout GridLayout

View：

AnalogClock button Chronometer ImageButton ImageView ProgressBar TextView ViewFlipper ListView GridView StackView AdapterViewFlipper ViewStub

不支持自定義View 所以具體使用RemoteViews還是aidl或者BroadCastReceiver還得看實際的需求。

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持武林網。

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