Make Expandable more extensible

app/src/main/java/com/topjohnwu/magisk/adapters/PolicyAdapter.java

@@ -19,7 +19,8 @@ import com.topjohnwu.magisk.container.Policy;
 import com.topjohnwu.magisk.database.MagiskDB;
 import com.topjohnwu.magisk.dialogs.CustomAlertDialog;
 import com.topjohnwu.magisk.dialogs.FingerprintAuthDialog;
-import com.topjohnwu.magisk.uicomponents.ArrowExpandedViewHolder;
+import com.topjohnwu.magisk.uicomponents.ArrowExpandable;
+import com.topjohnwu.magisk.uicomponents.Expandable;
 import com.topjohnwu.magisk.uicomponents.ExpandableViewHolder;
 import com.topjohnwu.magisk.uicomponents.SnackbarMaker;
 import com.topjohnwu.magisk.utils.FingerprintHelper;
@@ -160,12 +161,12 @@ public class PolicyAdapter extends RecyclerView.Adapter<PolicyAdapter.ViewHolder
         @BindView(R.id.delete) ImageView delete;
         @BindView(R.id.more_info) ImageView moreInfo;
 
-        ExpandableViewHolder settings;
+        Expandable settings;
 
         public ViewHolder(View itemView) {
             super(itemView);
             new PolicyAdapter$ViewHolder_ViewBinding(this, itemView);
-            settings = new ArrowExpandedViewHolder(expandLayout, arrow);
+            settings = new ArrowExpandable(new ExpandableViewHolder(expandLayout), arrow);
         }
     }
 }

app/src/main/java/com/topjohnwu/magisk/fragments/MagiskFragment.java

@@ -31,7 +31,8 @@ import com.topjohnwu.magisk.dialogs.MagiskInstallDialog;
 import com.topjohnwu.magisk.dialogs.ManagerInstallDialog;
 import com.topjohnwu.magisk.dialogs.UninstallDialog;
 import com.topjohnwu.magisk.tasks.CheckUpdates;
-import com.topjohnwu.magisk.uicomponents.ArrowExpandedViewHolder;
+import com.topjohnwu.magisk.uicomponents.ArrowExpandable;
+import com.topjohnwu.magisk.uicomponents.Expandable;
 import com.topjohnwu.magisk.uicomponents.ExpandableViewHolder;
 import com.topjohnwu.magisk.uicomponents.MarkDownWindow;
 import com.topjohnwu.magisk.uicomponents.SafetyNet;
@@ -73,7 +74,7 @@ public class MagiskFragment extends BaseFragment
     private UpdateCardHolder manager;
     private SafetyNet safetyNet;
     private Transition transition;
-    private ExpandableViewHolder optionExpand;
+    private Expandable optionExpand;
 
     private void magiskInstall(View v) {
         // Show Manager update first
@@ -137,7 +138,7 @@ public class MagiskFragment extends BaseFragment
         unbinder = new MagiskFragment_ViewBinding(this, v);
         requireActivity().setTitle(R.string.magisk);
 
-        optionExpand = new ArrowExpandedViewHolder(optionExpandLayout, arrow);
+        optionExpand = new ArrowExpandable(new ExpandableViewHolder(optionExpandLayout), arrow);
         safetyNet = new SafetyNet(v);
         magisk = new UpdateCardHolder(inflater, root);
         manager = new UpdateCardHolder(inflater, root);

app/src/main/java/com/topjohnwu/magisk/uicomponents/ArrowExpandable.java

@@ -1,40 +1,39 @@
 package com.topjohnwu.magisk.uicomponents;
 
 import android.view.View;
-import android.view.ViewGroup;
 import android.view.animation.Animation;
 import android.view.animation.RotateAnimation;
 
-public class ArrowExpandedViewHolder extends ExpandableViewHolder {
+public class ArrowExpandable extends Expandable {
-
+    protected Expandable mBase;
     private View arrow;
 
-    public ArrowExpandedViewHolder(ViewGroup viewGroup, View arrow) {
+    public ArrowExpandable(Expandable base, View arrow) {
-        super(viewGroup);
+        mBase = base;
         this.arrow = arrow;
     }
 
     @Override
-    public void setExpanded(boolean expanded) {
+    public void onExpand() {
-        super.setExpanded(expanded);
+        mBase.onExpand();
-        if (arrow != null)
-            arrow.setRotation(expanded ? 180 : 0);
-    }
-
-    @Override
-    public void expand() {
-        super.expand();
         setRotate(new RotateAnimation(0, 180,
                 Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f));
     }
 
     @Override
-    public void collapse() {
+    public void onCollapse() {
-        super.collapse();
+        mBase.onCollapse();
         setRotate(new RotateAnimation(180, 0,
                 Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f));
     }
 
+    @Override
+    public void onSetExpanded(boolean expanded) {
+        mBase.onSetExpanded(expanded);
+        if (arrow != null)
+            arrow.setRotation(expanded ? 180 : 0);
+    }
+
     private void setRotate(RotateAnimation rotate) {
         rotate.setDuration(300);
         rotate.setFillAfter(true);

app/src/main/java/com/topjohnwu/magisk/uicomponents/Expandable.java

@@ -0,0 +1,40 @@
+package com.topjohnwu.magisk.uicomponents;
+
+public abstract class Expandable {
+
+    private boolean mExpanded = false;
+
+    public final boolean isExpanded() {
+        return mExpanded;
+    }
+
+    public final void setExpanded(boolean expanded) {
+        mExpanded = expanded;
+        onSetExpanded(expanded);
+    }
+
+    public final void expand() {
+        if (mExpanded)
+            return;
+        onExpand();
+        mExpanded = true;
+    }
+
+    public final void collapse() {
+        if (!mExpanded)
+            return;
+        onCollapse();
+        mExpanded = false;
+    }
+
+    protected abstract void onExpand();
+
+    protected abstract void onCollapse();
+
+    protected void onSetExpanded(boolean expanded) {
+        if (expanded)
+            onExpand();
+        else
+            onCollapse();
+    }
+}

app/src/main/java/com/topjohnwu/magisk/uicomponents/ExpandableViewHolder.java

@@ -5,11 +5,10 @@ import android.view.View;
 import android.view.ViewGroup;
 import android.view.ViewTreeObserver;
 
-public class ExpandableViewHolder {
+public class ExpandableViewHolder extends Expandable {
 
     private ViewGroup expandLayout;
     private ValueAnimator expandAnimator, collapseAnimator;
-    private boolean mExpanded = false;
     private int expandHeight = 0;
 
     public ExpandableViewHolder(ViewGroup viewGroup) {
@@ -34,30 +33,24 @@ public class ExpandableViewHolder {
                 });
     }
 
-    public boolean isExpanded() {
+    @Override
-        return mExpanded;
+    protected void onExpand() {
+        expandLayout.setVisibility(View.VISIBLE);
+        expandAnimator.start();
     }
 
-    public void setExpanded(boolean expanded) {
+    @Override
-        mExpanded = expanded;
+    protected void onCollapse() {
+        collapseAnimator.start();
+    }
+
+    @Override
+    protected void onSetExpanded(boolean expanded) {
         ViewGroup.LayoutParams layoutParams = expandLayout.getLayoutParams();
         layoutParams.height = expanded ? expandHeight : 0;
         expandLayout.setLayoutParams(layoutParams);
     }
 
-    public void expand() {
-        if (mExpanded) return;
-        expandLayout.setVisibility(View.VISIBLE);
-        expandAnimator.start();
-        mExpanded = true;
-    }
-
-    public void collapse() {
-        if (!mExpanded) return;
-        collapseAnimator.start();
-        mExpanded = false;
-    }
-
     private ValueAnimator slideAnimator(int start, int end) {
         ValueAnimator animator = ValueAnimator.ofInt(start, end);