Android 多桌面图标启动, 爬坑点击打开不同页面

备注 ：
MainActivity 正常带界面的UI
MainActivityBt 和 MainActivityUsb  是透明的，即 android:theme="@style/TranslucentTheme"

###场景1:只有MainActivity 设置成：android:launchMode="singleTask"
点击顺序：MainActivity > home键 > MainActivityBt > home键 > MainActivityUsb
日志如下：

2024-03-03 21:22:11.724 15131-15131 MultipleIcon            pid-15131                            D  MainActivity.onCreate
2024-03-03 21:22:11.729 15131-15131 MultipleIcon            pid-15131                            D  MainActivity.onStart
2024-03-03 21:22:11.730 15131-15131 MultipleIcon            pid-15131                            D  MainActivity.onResume
---------------------------- PROCESS STARTED (15131) for package com.ifeng.multipleicon ----------------------------
2024-03-03 21:22:14.817 15131-15131 MultipleIcon            com.ifeng.multipleicon               D  MainActivity.onStart
2024-03-03 21:22:14.817 15131-15131 MultipleIcon            com.ifeng.multipleicon               D  MainActivity.onResume
2024-03-03 21:22:17.948 15131-15131 MultipleIcon            com.ifeng.multipleicon               D  MainActivity.onStart
2024-03-03 21:22:17.949 15131-15131 MultipleIcon            com.ifeng.multipleicon               D  MainActivity.onResume

日志简化图： 并没有执行MainActivityBt.onCreate 和 MainActivityUsb.onCreate；而且MainActivity只会执行一次。

###场景2:三个都设置成：android:launchMode="singleTask"

点击顺序：MainActivity > home键 > MainActivityBt > home键 > MainActivityUsb

2024-03-03 21:26:49.050 15690-15690 MultipleIcon            pid-15690                            D  MainActivity.onCreate
2024-03-03 21:26:49.057 15690-15690 MultipleIcon            pid-15690                            D  MainActivity.onStart
2024-03-03 21:26:49.057 15690-15690 MultipleIcon            pid-15690                            D  MainActivity.onResume
---------------------------- PROCESS STARTED (15690) for package com.ifeng.multipleicon ----------------------------
2024-03-03 21:26:52.114 15690-15690 MultipleIcon            com.ifeng.multipleicon               D  MainActivityBt.onCreate
2024-03-03 21:26:52.117 15690-15690 MultipleIcon            com.ifeng.multipleicon               D  MainActivity.onStart
2024-03-03 21:26:52.136 15690-15690 MultipleIcon            com.ifeng.multipleicon               D  MainActivity.onNewIntent
2024-03-03 21:26:52.136 15690-15690 MultipleIcon            com.ifeng.multipleicon               D  MainActivity.onResume
2024-03-03 21:26:56.130 15690-15690 MultipleIcon            com.ifeng.multipleicon               D  MainActivityUsb.onCreate
2024-03-03 21:26:56.133 15690-15690 MultipleIcon            com.ifeng.multipleicon               D  MainActivity.onStart
2024-03-03 21:26:56.143 15690-15690 MultipleIcon            com.ifeng.multipleicon               D  MainActivity.onNewIntent
2024-03-03 21:26:56.144 15690-15690 MultipleIcon            com.ifeng.multipleicon               D  MainActivity.onResume

 

日志简化图： 都有执行MainActivityBt.onCreate 和 MainActivityUsb.onCreate；而且MainActivity也成功跳转了！

！！！注意点：
#1. 多图标入口，需要跳转对应页面，入口Activity需要设置成singleTask， 否则只会唤起现有后台的页面。

#2. 多图标入口，如果是公用一个页面，刷新数据需要在onCreate 和 onNewIntent 中刷新UI。

详细代码：
Manifest配置文件：

<applicationandroid:allowBackup="true"android:dataExtractionRules="@xml/data_extraction_rules"android:fullBackupContent="@xml/backup_rules"android:icon="@mipmap/ic_launcher"android:label="@string/app_name"android:roundIcon="@mipmap/ic_launcher_round"android:supportsRtl="true"android:theme="@style/Theme.MultipleIconApplication"tools:targetApi="31"><activityandroid:name=".MainActivityBt"android:label="BT"android:exported="true"android:launchMode="singleTask"android:theme="@style/TranslucentTheme"><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity><activityandroid:name=".MainActivityUsb"android:label="USB"android:exported="true"android:launchMode="singleTask"android:theme="@style/TranslucentTheme"><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity><activityandroid:name=".MainActivity"android:exported="true"android:label="@string/app_name"android:launchMode="singleTask"android:theme="@style/Theme.MultipleIconApplication"><intent-filter><action android:name="android.intent.action.MAIN" /><category android:name="android.intent.category.LAUNCHER" /></intent-filter></activity></application>

MainActivity相关刷新UI代码 ：

class MainActivity : AppCompatActivity() {private val type : String?get() = intent.getStringExtra("TYPE")// 第一次打开需要在这里刷新override fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)setContentView(R.layout.activity_main)Log.d("MultipleIcon", "MainActivity.onCreate")syncTypeDisplay()}override fun onStart() {super.onStart()Log.d("MultipleIcon", "MainActivity.onStart")}// 当非首次进入时，需要在这里刷新override fun onNewIntent(intent: Intent) {super.onNewIntent(intent)// 需要使用setIntent(intent)赋值给当前Activity的Intent.否则，后续的getIntent()都是得到老的Intent。setIntent(intent)  syncTypeDisplay()Log.d("MultipleIcon", "MainActivity.onNewIntent")}private fun syncTypeDisplay() {findViewById<TextView>(R.id.tv).text =  when(type){"BT" -> {"蓝牙音乐"}"USB" ->{"USB音乐"}else -> {"收音机"}}}override fun onResume() {super.onResume()Log.d("MultipleIcon", "MainActivity.onResume")}
}