Fix conversation media overview underline flicker.

app/src/main/java/org/thoughtcrime/securesms/components/ControllableTabLayout.java

@@ -4,6 +4,9 @@ import android.content.Context;
 import android.util.AttributeSet;
 import android.view.View;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
 import com.google.android.material.tabs.TabLayout;
 
 import java.util.List;
@@ -15,6 +18,8 @@ public class ControllableTabLayout extends TabLayout {
 
   private List<View> touchables;
 
+  private NewTabListener newTabListener;
+
   public ControllableTabLayout(Context context) {
     super(context);
   }
@@ -39,4 +44,28 @@ public class ControllableTabLayout extends TabLayout {
 
     super.setEnabled(enabled);
   }
+
+  public void setNewTabListener(@Nullable NewTabListener newTabListener) {
+    this.newTabListener = newTabListener;
+  }
+
+  @Override
+  public @NonNull Tab newTab() {
+    Tab tab = super.newTab();
+
+    if (newTabListener != null) {
+      newTabListener.onNewTab(tab);
+    }
+
+    return tab;
+  }
+
+  /**
+   * Allows implementor to modify tabs when they are created, before they are added to the tab layout.
+   * This is useful for loading custom views, to ensure that time is not spent inflating these views
+   * as the user is switching between pages.
+   */
+  public interface NewTabListener {
+    void onNewTab(@NonNull Tab tab);
+  }
 }

app/src/main/java/org/thoughtcrime/securesms/mediaoverview/MediaOverviewActivity.java

@@ -18,7 +18,6 @@ package org.thoughtcrime.securesms.mediaoverview;
 
 import android.content.Context;
 import android.content.Intent;
-import android.graphics.Typeface;
 import android.os.Bundle;
 import android.view.MenuItem;
 import android.view.View;
@@ -27,19 +26,19 @@ import android.widget.TextView;
 
 import androidx.annotation.NonNull;
 import androidx.annotation.StringRes;
-import androidx.appcompat.app.AlertDialog;
 import androidx.appcompat.widget.Toolbar;
-import androidx.core.content.ContextCompat;
 import androidx.fragment.app.Fragment;
 import androidx.fragment.app.FragmentManager;
 import androidx.fragment.app.FragmentStatePagerAdapter;
 import androidx.viewpager.widget.ViewPager;
 
+import com.google.android.material.dialog.MaterialAlertDialogBuilder;
 import com.google.android.material.tabs.TabLayout;
 
 import org.thoughtcrime.securesms.PassphraseRequiredActivity;
 import org.thoughtcrime.securesms.R;
 import org.thoughtcrime.securesms.components.AnimatingToggle;
+import org.thoughtcrime.securesms.components.ControllableTabLayout;
 import org.thoughtcrime.securesms.database.DatabaseFactory;
 import org.thoughtcrime.securesms.database.MediaDatabase;
 import org.thoughtcrime.securesms.database.MediaDatabase.Sorting;
@@ -51,6 +50,7 @@ import org.whispersystems.libsignal.util.Pair;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Objects;
 
 /**
  * Activity for displaying media attachments in-app
@@ -62,7 +62,7 @@ public final class MediaOverviewActivity extends PassphraseRequiredActivity {
   private final DynamicTheme dynamicTheme = new DynamicNoActionBarTheme();
 
   private Toolbar                toolbar;
-  private TabLayout              tabLayout;
+  private ControllableTabLayout  tabLayout;
   private ViewPager              viewPager;
   private TextView               sortOrder;
   private View                   sortOrderArrow;
@@ -98,6 +98,7 @@ public final class MediaOverviewActivity extends PassphraseRequiredActivity {
 
     boolean allThreads = threadId == MediaDatabase.ALL_THREADS;
 
+    tabLayout.setNewTabListener(new NewTabListener());
     tabLayout.addOnTabSelectedListener(new OnTabSelectedListener());
     fillTabLayoutIfFits(tabLayout);
     tabLayout.setupWithViewPager(viewPager);
@@ -221,7 +222,7 @@ public final class MediaOverviewActivity extends PassphraseRequiredActivity {
   }
 
   private void showSortOrderDialog(View v) {
-    new AlertDialog.Builder(MediaOverviewActivity.this)
+    new MaterialAlertDialogBuilder(MediaOverviewActivity.this)
       .setTitle(R.string.MediaOverviewActivity_Sort_by)
       .setSingleChoiceItems(R.array.MediaOverviewActivity_Sort_by,
         currentSorting.ordinal(),
@@ -286,39 +287,33 @@ public final class MediaOverviewActivity extends PassphraseRequiredActivity {
     }
   }
 
-  private static final class OnTabSelectedListener implements TabLayout.OnTabSelectedListener {
+  private static final class NewTabListener implements ControllableTabLayout.NewTabListener {
+    @Override
+    public void onNewTab(@NonNull TabLayout.Tab tab) {
+      View customView = tab.getCustomView();
+      if (customView == null) {
+        tab.setCustomView(R.layout.media_overview_tab_item);
+      }
+    }
+  }
 
-    private final Typeface tabUnselected = Typeface.create("sans-serif", Typeface.NORMAL);
+  private static final class OnTabSelectedListener implements TabLayout.OnTabSelectedListener {
-    private final Typeface tabSelected   = Typeface.create("sans-serif-medium", Typeface.NORMAL);
 
     @Override
     public void onTabSelected(@NonNull TabLayout.Tab tab) {
-      View view = getCustomView(tab);
+      MediaOverviewTabItem view = (MediaOverviewTabItem) Objects.requireNonNull(tab.getCustomView());
-      TextView title = view.findViewById(android.R.id.text1);
+      view.select();
-      title.setTypeface(tabSelected);
-      title.setTextColor(ContextCompat.getColor(view.getContext(), R.color.signal_inverse_primary));
     }
 
     @Override
     public void onTabUnselected(@NonNull TabLayout.Tab tab) {
-      View view = getCustomView(tab);
+      MediaOverviewTabItem view = (MediaOverviewTabItem) Objects.requireNonNull(tab.getCustomView());
-      TextView title = view.findViewById(android.R.id.text1);
+      view.unselect();
-      title.setTypeface(tabUnselected);
-      title.setTextColor(ContextCompat.getColor(view.getContext(), R.color.signal_text_secondary));
     }
 
     @Override
     public void onTabReselected(@NonNull TabLayout.Tab tab) {
       // Intentionally Blank.
     }
-
-    private @NonNull View getCustomView(@NonNull TabLayout.Tab tab) {
-      View customView = tab.getCustomView();
-      if (customView == null) {
-        tab.setCustomView(R.layout.custom_tab_layout_text);
-      }
-
-      return tab.getCustomView();
-    }
   }
 }

app/src/main/java/org/thoughtcrime/securesms/mediaoverview/MediaOverviewTabItem.kt

@@ -0,0 +1,39 @@
+package org.thoughtcrime.securesms.mediaoverview
+
+import android.content.Context
+import android.util.AttributeSet
+import android.widget.FrameLayout
+import android.widget.TextView
+import androidx.core.widget.doAfterTextChanged
+import org.thoughtcrime.securesms.R
+
+class MediaOverviewTabItem @JvmOverloads constructor(
+  context: Context,
+  attrs: AttributeSet? = null,
+  defStyleAttr: Int = 0
+) : FrameLayout(context, attrs, defStyleAttr) {
+
+  private lateinit var unselectedTextView: TextView
+  private lateinit var selectedTextView: TextView
+
+  override fun onFinishInflate() {
+    super.onFinishInflate()
+
+    unselectedTextView = findViewById(android.R.id.text1)
+    selectedTextView = findViewById(R.id.text1_bold)
+
+    unselectedTextView.doAfterTextChanged {
+      selectedTextView.text = it
+    }
+  }
+
+  fun select() {
+    unselectedTextView.alpha = 0f
+    selectedTextView.alpha = 1f
+  }
+
+  fun unselect() {
+    unselectedTextView.alpha = 1f
+    selectedTextView.alpha = 0f
+  }
+}

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

@@ -1,10 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<TextView xmlns:android="http://schemas.android.com/apk/res/android"
-    xmlns:tools="http://schemas.android.com/tools"
-    android:id="@android:id/text1"
-    android:layout_width="wrap_content"
-    android:layout_height="wrap_content"
-    android:gravity="center"
-    android:textAppearance="@style/TextAppearance.Signal.Body2"
-    android:maxLines="2"
-    tools:text="Media" />

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

@@ -0,0 +1,30 @@
+<?xml version="1.0" encoding="utf-8"?>
+<org.thoughtcrime.securesms.mediaoverview.MediaOverviewTabItem xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content">
+
+    <TextView
+        android:id="@android:id/text1"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:alpha="1"
+        android:gravity="center"
+        android:maxLines="2"
+        android:textAppearance="@style/TextAppearance.Signal.Body2"
+        android:textColor="@color/signal_text_secondary"
+        tools:text="Media" />
+
+    <TextView
+        android:id="@+id/text1_bold"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:alpha="0"
+        android:fontFamily="sans-serif-medium"
+        android:gravity="center"
+        android:maxLines="2"
+        android:textAppearance="@style/TextAppearance.Signal.Body2"
+        android:textColor="@color/signal_text_primary"
+        tools:text="Media" />
+
+</org.thoughtcrime.securesms.mediaoverview.MediaOverviewTabItem>