fix: DummyActivity: implement installation progress dialog

* This fixes the apparent stalling when installing / cloning
  applications.
* Also moves apk reading to another thread.

app/src/main/AndroidManifest.xml

@@ -41,7 +41,7 @@
         <activity android:name=".ui.DummyActivity"
             android:excludeFromRecents="true"
             android:launchMode="singleTask"
-            android:theme="@android:style/Theme.Translucent.NoTitleBar">
+            android:theme="@style/Theme.AppCompat.Translucent.NoTitleBar">
             <intent-filter>
                 <action android:name="net.typeblog.shelter.action.FINALIZE_PROVISION" />
                 <action android:name="net.typeblog.shelter.action.START_SERVICE" />

app/src/main/java/net/typeblog/shelter/ui/DummyActivity.java

@@ -3,6 +3,7 @@ package net.typeblog.shelter.ui;
 import android.Manifest;
 import android.app.Activity;
 import android.app.PendingIntent;
+import android.app.ProgressDialog;
 import android.app.admin.DevicePolicyManager;
 import android.content.ComponentName;
 import android.content.Intent;
@@ -15,10 +16,14 @@ import android.os.Bundle;
 import android.os.IBinder;
 import android.os.RemoteException;
 import android.os.StrictMode;
+import android.view.LayoutInflater;
+import android.view.ViewGroup;
+import android.widget.ProgressBar;
 import android.widget.Toast;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+import androidx.appcompat.app.AlertDialog;
 
 import net.typeblog.shelter.R;
 import net.typeblog.shelter.ShelterApplication;
@@ -29,6 +34,7 @@ import net.typeblog.shelter.services.IFileShuttleService;
 import net.typeblog.shelter.services.IFileShuttleServiceCallback;
 import net.typeblog.shelter.util.AuthenticationUtility;
 import net.typeblog.shelter.util.FileProviderProxy;
+import net.typeblog.shelter.util.InstallationProgressListener;
 import net.typeblog.shelter.util.LocalStorageManager;
 import net.typeblog.shelter.util.SettingsManager;
 import net.typeblog.shelter.util.Utility;
@@ -314,20 +320,40 @@ public class DummyActivity extends Activity {
         PackageInstaller.SessionParams params = new PackageInstaller.SessionParams(
                 PackageInstaller.SessionParams.MODE_FULL_INSTALL);
         int sessionId = pi.createSession(params);
+
+        // Show the progress dialog first
+        pi.registerSessionCallback(new InstallationProgressListener(this, pi, sessionId));
+
         PackageInstaller.Session session = pi.openSession(sessionId);
+        doInstallPackageQ(uri, session, () -> {
+            // We have finished piping the streams, show the progress as 10%
+            session.setStagingProgress(0.1f);
 
-        InputStream is = getContentResolver().openInputStream(uri);
-        OutputStream os = session.openWrite(UUID.randomUUID().toString(), 0, is.available());
-        Utility.pipe(is, os);
-        session.fsync(os);
-        os.close();
-        is.close();
+            // Commit the session
+            Intent intent = new Intent(this, DummyActivity.class);
+            intent.setAction(PACKAGEINSTALLER_CALLBACK);
+            PendingIntent pendingIntent = PendingIntent.getActivity(this, 0,
+                    intent, PendingIntent.FLAG_UPDATE_CURRENT);
+            session.commit(pendingIntent.getIntentSender());
+        });
+    }
 
-        Intent intent = new Intent(this, DummyActivity.class);
-        intent.setAction(PACKAGEINSTALLER_CALLBACK);
-        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0,
-                intent, PendingIntent.FLAG_UPDATE_CURRENT);
-        session.commit(pendingIntent.getIntentSender());
+    // The background part of the installation process on Q (reading APKs etc)
+    // that must be executed on another thread
+    // Put them in background to avoid stalling the UI thread
+    private void doInstallPackageQ(Uri uri, PackageInstaller.Session session, Runnable callback) {
+        new Thread(() -> {
+            try (InputStream is = getContentResolver().openInputStream(uri);
+                 OutputStream os = session.openWrite(UUID.randomUUID().toString(), 0, is.available())
+            ) {
+                Utility.pipe(is, os);
+                session.fsync(os);
+            } catch (IOException e) {
+
+            }
+
+            runOnUiThread(callback);
+        }).start();
     }
 
     private void actionUninstallPackage() {

app/src/main/java/net/typeblog/shelter/util/InstallationProgressListener.java

@@ -0,0 +1,67 @@
+package net.typeblog.shelter.util;
+
+import android.app.Activity;
+import android.content.pm.PackageInstaller;
+import android.view.LayoutInflater;
+import android.view.ViewGroup;
+import android.widget.ProgressBar;
+
+import androidx.appcompat.app.AlertDialog;
+
+import net.typeblog.shelter.R;
+
+public class InstallationProgressListener extends PackageInstaller.SessionCallback {
+    private AlertDialog mDialog;
+    private ProgressBar mProgress;
+    private int mSessionId;
+    private PackageInstaller mPi;
+
+    // Create a listener from an activity, and show a progress dialog for the sessionId
+    // Only cares about the one sessionId provided here.
+    // The caller is responsible for registering the callback;
+    // however, this class will remove itself once the session has been finished.
+    public InstallationProgressListener(Activity activity, PackageInstaller pi, int sessionId) {
+        mPi = pi;
+
+        ViewGroup layout = (ViewGroup) LayoutInflater.from(activity)
+                .inflate(R.layout.progress_dialog, (ViewGroup) activity.getWindow().getDecorView(), false);
+        mProgress = layout.findViewById(R.id.progress);
+
+        mDialog = new AlertDialog.Builder(activity)
+                .setCancelable(false)
+                .setTitle(R.string.app_installing)
+                .setView(layout)
+                .create();
+        mDialog.show();
+    }
+
+    @Override
+    public void onCreated(int sessionId) {
+
+    }
+
+    @Override
+    public void onBadgingChanged(int sessionId) {
+
+    }
+
+    @Override
+    public void onActiveChanged(int sessionId, boolean active) {
+
+    }
+
+    @Override
+    public void onProgressChanged(int sessionId, float progress) {
+        mProgress.setProgress((int) (progress * 100));
+    }
+
+    @Override
+    public void onFinished(int sessionId, boolean success) {
+        if (sessionId != mSessionId) {
+            return;
+        }
+
+        mDialog.hide();
+        mPi.unregisterSessionCallback(this);
+    }
+}

app/src/main/res/layout/progress_dialog.xml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="wrap_content"
+    android:layout_gravity="center">
+
+    <ProgressBar
+        android:id="@+id/progress"
+        style="@android:style/Widget.Material.ProgressBar.Horizontal"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginStart="20dp"
+        android:layout_marginEnd="20dp"
+        android:layout_marginTop="10dp"
+        android:indeterminate="false"
+        android:max="100"/>
+
+</FrameLayout>

app/src/main/res/values/strings.xml

@@ -17,6 +17,7 @@
     <string name="service_auto_freeze_title">Auto-freeze pending</string>
     <string name="service_auto_freeze_desc">Shelter will auto-freeze apps launched from \"Unfreeze &amp; Launch\" on the next screen lock event.</string>
     <string name="service_auto_freeze_now">Freeze Now</string>
+    <string name="app_installing">Installing...</string>
 
     <!-- Main UI -->
     <string name="fragment_profile_main">Main</string>

app/src/main/res/values/styles.xml

@@ -15,4 +15,13 @@
         <item name="android:textColorPrimary">@color/colorAccent</item>
     </style>
 
+    <!-- For DummyActivity -->
+    <style name="Theme.AppCompat.Translucent.NoTitleBar" parent="Theme.AppCompat.Light.NoActionBar">
+        <item name="android:windowNoTitle">true</item>
+        <item name="android:windowBackground">@android:color/transparent</item>
+        <item name="android:colorBackgroundCacheHint">@null</item>
+        <item name="android:windowIsTranslucent">true</item>
+        <item name="android:windowAnimationStyle">@android:style/Animation</item>
+    </style>
+
 </resources>