Chooser fragments shouldn't save instance state.

 1. I can't think of any way we could possibly trigger the fragment's
    load-from-saved-state flow since Sharesheet isn't in history.

 2. If this flow was ever triggered for the "stacked app" fragment
    we would crash. Our first step in restoring from a `Bundle` is
    to make an unsafe downcast to `MultiDisplayResolveInfo` and
    invoke one of its subclass methods, but `MultiDisplayResolveInfo`
    doesn't actually implement `Parcelable` correctly; it inherits
    the relationship via `DisplayResolveInfo`, including its
    `Creator`, so any attempt to restore the parceled target would
    get a concrete `DisplayResolveInfo`, slicing off any data
    specific to its old multi-target type (and, of course, leaving
    an object that can't use any of the subclass methods).

 3. Support for this flow seems to be the only reason that
    `DisplayResolveInfo` implements `Parcelable` at all, so as part
    of go/chooser-targetinfo-cleanup we should prune this (broken and
    dead) code and then go on to remove all of that complexity from
    the `TargetInfo` API.

Test: manual & presubmit
Bug: 202167050
Change-Id: Ida3b74edf975e3c1353e757b37e4cfadf716d5c3

4 files changed, 125 insertions, 151 deletions

diff --git a/java/src/com/android/intentresolver/ChooserActivity.java b/java/src/com/android/intentresolver/ChooserActivity.java
index a73424bf..b0e2450b 100644
--- a/java/src/com/android/intentresolver/ChooserActivity.java
+++ b/java/src/com/android/intentresolver/ChooserActivity.java
@@ -271,8 +271,6 @@ public class ChooserActivity extends ResolverActivity implements
     private int mLastNumberOfChildren = -1;
     private int mMaxTargetsPerRow = 1;
 
-    private static final String TARGET_DETAILS_FRAGMENT_TAG = "targetDetailsFragment";
-
     private static final int MAX_LOG_RANK_POSITION = 12;
 
     private static final int MAX_EXTRA_INITIAL_INTENTS = 2;
@@ -1718,33 +1716,28 @@ public class ChooserActivity extends ResolverActivity implements
             return;
         }
 
-        ChooserTargetActionsDialogFragment fragment = new ChooserTargetActionsDialogFragment();
-        Bundle bundle = new Bundle();
-
-        bundle.putParcelable(ChooserTargetActionsDialogFragment.USER_HANDLE_KEY,
-                mChooserMultiProfilePagerAdapter.getCurrentUserHandle());
-        bundle.putParcelableArrayList(ChooserTargetActionsDialogFragment.TARGET_INFOS_KEY,
-                new ArrayList<>(targetList));
-
-        if (targetInfo.isSelectableTargetInfo()) {
-            // TODO: migrate this condition to polymorphic calls on TargetInfo (maybe in some cases
-            // we can safely drop the `isSelectableTargetInfo()` condition and populate the bundle
-            // with any non-null values we find, regardless of the target type?)
-            bundle.putString(ChooserTargetActionsDialogFragment.SHORTCUT_ID_KEY,
-                    targetInfo.getChooserTarget().getIntentExtras().getString(
-                            Intent.EXTRA_SHORTCUT_ID));
-            bundle.putBoolean(ChooserTargetActionsDialogFragment.IS_SHORTCUT_PINNED_KEY,
-                    targetInfo.isPinned());
-            bundle.putParcelable(ChooserTargetActionsDialogFragment.INTENT_FILTER_KEY,
-                    getTargetIntentFilter());
-            if (targetInfo.getDisplayLabel() != null) {
-                bundle.putString(ChooserTargetActionsDialogFragment.SHORTCUT_TITLE_KEY,
-                        targetInfo.getDisplayLabel().toString());
-            }
-        }
-
-        fragment.setArguments(bundle);
-        fragment.show(getSupportFragmentManager(), TARGET_DETAILS_FRAGMENT_TAG);
+        // TODO: implement these type-conditioned behaviors polymorphically, and consider moving
+        // the logic into `ChooserTargetActionsDialogFragment.show()`.
+        boolean isShortcutPinned = targetInfo.isSelectableTargetInfo() && targetInfo.isPinned();
+        IntentFilter intentFilter =
+                targetInfo.isSelectableTargetInfo() ? getTargetIntentFilter() : null;
+        String shortcutTitle = targetInfo.isSelectableTargetInfo()
+                ? targetInfo.getDisplayLabel().toString() : null;
+        String shortcutIdKey = targetInfo.isSelectableTargetInfo()
+                ? targetInfo
+                        .getChooserTarget()
+                        .getIntentExtras()
+                        .getString(Intent.EXTRA_SHORTCUT_ID)
+                : null;
+
+        ChooserTargetActionsDialogFragment.show(
+                getSupportFragmentManager(),
+                targetList,
+                mChooserMultiProfilePagerAdapter.getCurrentUserHandle(),
+                shortcutIdKey,
+                shortcutTitle,
+                isShortcutPinned,
+                intentFilter);
     }
 
     private void modifyTargetIntent(Intent in) {
@@ -1801,16 +1794,11 @@ public class ChooserActivity extends ResolverActivity implements
         if (targetInfo.isMultiDisplayResolveInfo()) {
             MultiDisplayResolveInfo mti = (MultiDisplayResolveInfo) targetInfo;
             if (!mti.hasSelected()) {
-                ChooserStackedAppDialogFragment f = new ChooserStackedAppDialogFragment();
-                Bundle b = new Bundle();
-                b.putParcelable(ChooserTargetActionsDialogFragment.USER_HANDLE_KEY,
+                ChooserStackedAppDialogFragment.show(
+                        getSupportFragmentManager(),
+                        mti,
+                        which,
                         mChooserMultiProfilePagerAdapter.getCurrentUserHandle());
-                b.putObject(ChooserStackedAppDialogFragment.MULTI_DRI_KEY,
-                        mti);
-                b.putInt(ChooserStackedAppDialogFragment.WHICH_KEY, which);
-                f.setArguments(b);
-
-                f.show(getSupportFragmentManager(), TARGET_DETAILS_FRAGMENT_TAG);
                 return;
             }
         }
diff --git a/java/src/com/android/intentresolver/ChooserStackedAppDialogFragment.java b/java/src/com/android/intentresolver/ChooserStackedAppDialogFragment.java
index b4e427a1..2cfceeae 100644
--- a/java/src/com/android/intentresolver/ChooserStackedAppDialogFragment.java
+++ b/java/src/com/android/intentresolver/ChooserStackedAppDialogFragment.java
@@ -20,9 +20,10 @@ package com.android.intentresolver;
 import android.content.DialogInterface;
 import android.content.pm.PackageManager;
 import android.graphics.drawable.Drawable;
-import android.os.Bundle;
 import android.os.UserHandle;
 
+import androidx.fragment.app.FragmentManager;
+
 import com.android.intentresolver.chooser.DisplayResolveInfo;
 import com.android.intentresolver.chooser.MultiDisplayResolveInfo;
 
@@ -30,29 +31,39 @@ import com.android.intentresolver.chooser.MultiDisplayResolveInfo;
  * Shows individual actions for a "stacked" app target - such as an app with multiple posting
  * streams represented in the Sharesheet.
  */
-public class ChooserStackedAppDialogFragment extends ChooserTargetActionsDialogFragment
-        implements DialogInterface.OnClickListener {
-
-    static final String WHICH_KEY = "which_key";
-    static final String MULTI_DRI_KEY = "multi_dri_key";
-
-    private MultiDisplayResolveInfo mMultiDisplayResolveInfo;
-    private int mParentWhich;
-
-    public ChooserStackedAppDialogFragment() {}
+public class ChooserStackedAppDialogFragment extends ChooserTargetActionsDialogFragment {
 
-    void setStateFromBundle(Bundle b) {
-        mMultiDisplayResolveInfo = (MultiDisplayResolveInfo) b.get(MULTI_DRI_KEY);
-        mTargetInfos = mMultiDisplayResolveInfo.getAllDisplayTargets();
-        mUserHandle = (UserHandle) b.get(USER_HANDLE_KEY);
-        mParentWhich = b.getInt(WHICH_KEY);
+    /**
+     * Display a fragment for the user to select one of the members of a target "stack."
+     * @param stackedTarget The display info for the full stack to select within.
+     * @param stackedTargetParentWhich The "which" value that the {@link ChooserActivity} uses to
+     * identify the {@code stackedTarget} as presented in the chooser menu UI. If the user selects
+     * a target in this fragment, the selection will be saved in the {@link MultiDisplayResolveInfo}
+     * and then the {@link ChooserActivity} will receive a {@code #startSelected()} callback using
+     * this "which" value to identify the stack that's now unambiguously resolved.
+     * @param userHandle
+     *
+     * TODO: consider taking a client-provided callback instead of {@code stackedTargetParentWhich}
+     * to avoid coupling with {@link ChooserActivity}'s mechanism for handling the selection.
+     */
+    public static void show(
+            FragmentManager fragmentManager,
+            MultiDisplayResolveInfo stackedTarget,
+            int stackedTargetParentWhich,
+            UserHandle userHandle) {
+        ChooserStackedAppDialogFragment fragment = new ChooserStackedAppDialogFragment(
+                stackedTarget, stackedTargetParentWhich, userHandle);
+        fragment.show(fragmentManager, TARGET_DETAILS_FRAGMENT_TAG);
     }
 
+    private final MultiDisplayResolveInfo mMultiDisplayResolveInfo;
+    private final int mParentWhich;
+
     @Override
-    public void onSaveInstanceState(Bundle outState) {
-        super.onSaveInstanceState(outState);
-        outState.putInt(WHICH_KEY, mParentWhich);
-        outState.putParcelable(MULTI_DRI_KEY, mMultiDisplayResolveInfo);
+    public void onClick(DialogInterface dialog, int which) {
+        mMultiDisplayResolveInfo.setSelected(which);
+        ((ChooserActivity) getActivity()).startSelected(mParentWhich, false, true);
+        dismiss();
     }
 
     @Override
@@ -63,15 +74,16 @@ public class ChooserStackedAppDialogFragment extends ChooserTargetActionsDialogF
 
     @Override
     protected Drawable getItemIcon(DisplayResolveInfo dri) {
-
         // Show no icon for the group disambig dialog, null hides the imageview
         return null;
     }
 
-    @Override
-    public void onClick(DialogInterface dialog, int which) {
-        mMultiDisplayResolveInfo.setSelected(which);
-        ((ChooserActivity) getActivity()).startSelected(mParentWhich, false, true);
-        dismiss();
+    private ChooserStackedAppDialogFragment(
+            MultiDisplayResolveInfo stackedTarget,
+            int stackedTargetParentWhich,
+            UserHandle userHandle) {
+        super(stackedTarget.getAllDisplayTargets(), userHandle);
+        mMultiDisplayResolveInfo = stackedTarget;
+        mParentWhich = stackedTargetParentWhich;
     }
 }
diff --git a/java/src/com/android/intentresolver/ChooserTargetActionsDialogFragment.java b/java/src/com/android/intentresolver/ChooserTargetActionsDialogFragment.java
index 61b54fa9..f4d4a6d1 100644
--- a/java/src/com/android/intentresolver/ChooserTargetActionsDialogFragment.java
+++ b/java/src/com/android/intentresolver/ChooserTargetActionsDialogFragment.java
@@ -49,11 +49,11 @@ import android.widget.ImageView;
 import android.widget.TextView;
 
 import androidx.fragment.app.DialogFragment;
+import androidx.fragment.app.FragmentManager;
 import androidx.recyclerview.widget.RecyclerView;
 
 import com.android.intentresolver.chooser.DisplayResolveInfo;
 
-import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
 import java.util.stream.Collectors;
@@ -64,68 +64,61 @@ import java.util.stream.Collectors;
 public class ChooserTargetActionsDialogFragment extends DialogFragment
         implements DialogInterface.OnClickListener {
 
-    protected ArrayList<DisplayResolveInfo> mTargetInfos = new ArrayList<>();
-    protected UserHandle mUserHandle;
-    protected String mShortcutId;
-    protected String mShortcutTitle;
-    protected boolean mIsShortcutPinned;
-    protected IntentFilter mIntentFilter;
+    protected final static String TARGET_DETAILS_FRAGMENT_TAG = "targetDetailsFragment";
 
-    public static final String USER_HANDLE_KEY = "user_handle";
-    public static final String TARGET_INFOS_KEY = "target_infos";
-    public static final String SHORTCUT_ID_KEY = "shortcut_id";
-    public static final String SHORTCUT_TITLE_KEY = "shortcut_title";
-    public static final String IS_SHORTCUT_PINNED_KEY = "is_shortcut_pinned";
-    public static final String INTENT_FILTER_KEY = "intent_filter";
+    private final List<DisplayResolveInfo> mTargetInfos;
+    private final UserHandle mUserHandle;
+    private final boolean mIsShortcutPinned;
 
-    public ChooserTargetActionsDialogFragment() {}
+    @Nullable
+    private final String mShortcutId;
+
+    @Nullable
+    private final String mShortcutTitle;
+
+    @Nullable
+    private final IntentFilter mIntentFilter;
+
+    public static void show(
+            FragmentManager fragmentManager,
+            List<DisplayResolveInfo> targetInfos,
+            UserHandle userHandle,
+            @Nullable String shortcutId,
+            @Nullable String shortcutTitle,
+            boolean isShortcutPinned,
+            @Nullable IntentFilter intentFilter) {
+        ChooserTargetActionsDialogFragment fragment = new ChooserTargetActionsDialogFragment(
+                targetInfos,
+                userHandle,
+                shortcutId,
+                shortcutTitle,
+                isShortcutPinned,
+                intentFilter);
+        fragment.show(fragmentManager, TARGET_DETAILS_FRAGMENT_TAG);
+    }
 
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
+
         if (savedInstanceState != null) {
-            setStateFromBundle(savedInstanceState);
-        } else {
-            setStateFromBundle(getArguments());
+            // Bail. It's probably not possible to trigger reloading our fragments from a saved
+            // instance since Sharesheet isn't kept in history and the entire session will probably
+            // be lost under any conditions that would've triggered our retention. Nevertheless, if
+            // we ever *did* try to load from a saved state, we wouldn't be able to populate valid
+            // data (since we wouldn't be able to get back our original TargetInfos if we had to
+            // restore them from a Bundle).
+            dismissAllowingStateLoss();
         }
     }
 
-    void setStateFromBundle(Bundle b) {
-        mTargetInfos = (ArrayList<DisplayResolveInfo>) b.get(TARGET_INFOS_KEY);
-        mUserHandle = (UserHandle) b.get(USER_HANDLE_KEY);
-        mShortcutId = b.getString(SHORTCUT_ID_KEY);
-        mShortcutTitle = b.getString(SHORTCUT_TITLE_KEY);
-        mIsShortcutPinned = b.getBoolean(IS_SHORTCUT_PINNED_KEY);
-        mIntentFilter = (IntentFilter) b.get(INTENT_FILTER_KEY);
-    }
-
-    @Override
-    public void onSaveInstanceState(Bundle outState) {
-        super.onSaveInstanceState(outState);
-
-        outState.putParcelable(ChooserTargetActionsDialogFragment.USER_HANDLE_KEY,
-                mUserHandle);
-        outState.putParcelableArrayList(ChooserTargetActionsDialogFragment.TARGET_INFOS_KEY,
-                mTargetInfos);
-        outState.putString(ChooserTargetActionsDialogFragment.SHORTCUT_ID_KEY, mShortcutId);
-        outState.putBoolean(ChooserTargetActionsDialogFragment.IS_SHORTCUT_PINNED_KEY,
-                mIsShortcutPinned);
-        outState.putString(ChooserTargetActionsDialogFragment.SHORTCUT_TITLE_KEY, mShortcutTitle);
-        outState.putParcelable(ChooserTargetActionsDialogFragment.INTENT_FILTER_KEY, mIntentFilter);
-    }
-
     /**
-     * Recreate the layout from scratch to match new Sharesheet redlines
+     * Build the menu UI according to our design spec.
      */
     @Override
     public View onCreateView(LayoutInflater inflater,
             @Nullable ViewGroup container,
             Bundle savedInstanceState) {
-        if (savedInstanceState != null) {
-            setStateFromBundle(savedInstanceState);
-        } else {
-            setStateFromBundle(getArguments());
-        }
         // Make the background transparent to show dialog rounding
         Optional.of(getDialog()).map(Dialog::getWindow)
                 .ifPresent(window -> {
@@ -294,4 +287,24 @@ public class ChooserTargetActionsDialogFragment extends DialogFragment
     private boolean isShortcutTarget() {
         return mShortcutId != null;
     }
+
+    protected ChooserTargetActionsDialogFragment(
+            List<DisplayResolveInfo> targetInfos, UserHandle userHandle) {
+        this(targetInfos, userHandle, null, null, false, null);
+    }
+
+    private ChooserTargetActionsDialogFragment(
+            List<DisplayResolveInfo> targetInfos,
+            UserHandle userHandle,
+            @Nullable String shortcutId,
+            @Nullable String shortcutTitle,
+            boolean isShortcutPinned,
+            @Nullable IntentFilter intentFilter) {
+        mTargetInfos = targetInfos;
+        mUserHandle = userHandle;
+        mShortcutId = shortcutId;
+        mShortcutTitle = shortcutTitle;
+        mIsShortcutPinned = isShortcutPinned;
+        mIntentFilter = intentFilter;
+    }
 }
diff --git a/java/src/com/android/intentresolver/chooser/DisplayResolveInfo.java b/java/src/com/android/intentresolver/chooser/DisplayResolveInfo.java
index cd6828c7..daa69152 100644
--- a/java/src/com/android/intentresolver/chooser/DisplayResolveInfo.java
+++ b/java/src/com/android/intentresolver/chooser/DisplayResolveInfo.java
@@ -27,8 +27,6 @@ import android.content.pm.ApplicationInfo;
 import android.content.pm.ResolveInfo;
 import android.graphics.drawable.Drawable;
 import android.os.Bundle;
-import android.os.Parcel;
-import android.os.Parcelable;
 import android.os.UserHandle;
 
 import com.android.intentresolver.ResolverActivity;
@@ -42,7 +40,7 @@ import java.util.List;
  * A TargetInfo plus additional information needed to render it (such as icon and label) and
  * resolve it to an activity.
  */
-public class DisplayResolveInfo implements TargetInfo, Parcelable {
+public class DisplayResolveInfo implements TargetInfo {
     private final ResolveInfo mResolveInfo;
     private CharSequence mDisplayLabel;
     private Drawable mDisplayIcon;
@@ -237,41 +235,4 @@ public class DisplayResolveInfo implements TargetInfo, Parcelable {
     public void setPinned(boolean pinned) {
         mPinned = pinned;
     }
-
-    @Override
-    public int describeContents() {
-        return 0;
-    }
-
-    @Override
-    public void writeToParcel(Parcel dest, int flags) {
-        dest.writeCharSequence(mDisplayLabel);
-        dest.writeCharSequence(mExtendedInfo);
-        dest.writeParcelable(mResolvedIntent, 0);
-        dest.writeTypedList(mSourceIntents);
-        dest.writeBoolean(mIsSuspended);
-        dest.writeBoolean(mPinned);
-        dest.writeParcelable(mResolveInfo, 0);
-    }
-
-    public static final Parcelable.Creator<DisplayResolveInfo> CREATOR =
-            new Parcelable.Creator<DisplayResolveInfo>() {
-        public DisplayResolveInfo createFromParcel(Parcel in) {
-            return new DisplayResolveInfo(in);
-        }
-
-        public DisplayResolveInfo[] newArray(int size) {
-            return new DisplayResolveInfo[size];
-        }
-    };
-
-    private DisplayResolveInfo(Parcel in) {
-        mDisplayLabel = in.readCharSequence();
-        mExtendedInfo = in.readCharSequence();
-        mResolvedIntent = in.readParcelable(null /* ClassLoader */, android.content.Intent.class);
-        in.readTypedList(mSourceIntents, Intent.CREATOR);
-        mIsSuspended = in.readBoolean();
-        mPinned = in.readBoolean();
-        mResolveInfo = in.readParcelable(null /* ClassLoader */, android.content.pm.ResolveInfo.class);
-    }
 }