Feature: Support filtering custom emoji in reaction view (#836)

* Support filtering custom emojis in reaction keyboard.

* Move creation of EditText to conditional block.

* Clear unused comment

* Update requests variable when publishing filter results so the images displayed will be correct.

* Combine text fields in emoji reaction keyboard, create new initializer for EmojiCategory so it can be copied properly.

* Performance optimization and fixed a typo in filter.

* improve layout

---------

Co-authored-by: sk <sk22@mailbox.org>

mastodon/src/main/java/org/joinmastodon/android/model/EmojiCategory.java

@@ -1,5 +1,6 @@
 package org.joinmastodon.android.model;
 
+import java.util.ArrayList;
 import java.util.List;
 
 public class EmojiCategory{
@@ -10,4 +11,8 @@ public class EmojiCategory{
 		this.title=title;
 		this.emojis=emojis;
 	}
+	public EmojiCategory(EmojiCategory category){
+		this.title = category.title;
+		this.emojis = new ArrayList<>(category.emojis);
+	}
 }

mastodon/src/main/java/org/joinmastodon/android/ui/CustomEmojiPopupKeyboard.java

@@ -17,6 +17,8 @@ import android.view.View;
 import android.view.ViewGroup;
 import android.view.inputmethod.InputMethodManager;
 import android.widget.EditText;
+import android.widget.Filter;
+import android.widget.Filterable;
 import android.widget.FrameLayout;
 import android.widget.ImageButton;
 import android.widget.ImageView;
@@ -34,6 +36,7 @@ import org.joinmastodon.android.model.Emoji;
 import org.joinmastodon.android.model.EmojiCategory;
 import org.joinmastodon.android.ui.utils.UiUtils;
 
+import java.util.ArrayList;
 import java.util.List;
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
@@ -139,43 +142,52 @@ public class CustomEmojiPopupKeyboard extends PopupKeyboard{
 
 		ll.addView(list, new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 0, 1f));
 
-		FrameLayout bottomPanel=new FrameLayout(activity);
-		bottomPanel.setPadding(V.dp(16), V.dp(8), V.dp(16), V.dp(8));
-		bottomPanel.setBackgroundResource(R.drawable.bg_m3_surface2);
-		ll.addView(bottomPanel, new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
-
 		if(forReaction){
-			InputMethodManager imm=(InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE);
+			FrameLayout topPanel=new FrameLayout(activity);
+			topPanel.setPadding(V.dp(16), V.dp(12), V.dp(16), V.dp(12));
+			topPanel.setBackgroundResource(R.drawable.bg_m3_surface2);
+			ll.addView(topPanel, 0, new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
 			
-			// TODO: support filtering custom emoji
+			InputMethodManager imm=(InputMethodManager) activity.getSystemService(Context.INPUT_METHOD_SERVICE);
 			EditText input=new EditText(activity);
 			input.setHint(R.string.sk_enter_emoji_hint);
 			input.addTextChangedListener(new TextWatcher() {
 				@Override
-				public void onTextChanged(CharSequence s, int start, int before, int count) {
+				public void onTextChanged(CharSequence s, int start, int before, int count){
-					if (!s.toString().isEmpty()) {
+					// Only check the emoji regex if the text field was empty before
-						if (emojiRegex.matcher(s.toString()).find()) {
+					if(start == 0){
+						if(emojiRegex.matcher(s.toString()).find()){
 							imm.hideSoftInputFromWindow(input.getWindowToken(), 0);
 							listener.onEmojiSelected(s.toString().substring(before));
 							input.getText().clear();
-						} else {
-							Toast.makeText(activity, R.string.sk_enter_emoji_toast, Toast.LENGTH_SHORT).show();
-							input.getText().clear();
 						}
 					}
+					for(int i=0; i<adapter.getAdapterCount(); i++){
+						SingleCategoryAdapter currentAdapter=(SingleCategoryAdapter) adapter.getAdapterAt(i);
+						currentAdapter.getFilter().filter(s.toString());
+					}
 				}
 
 				@Override public void beforeTextChanged(CharSequence s, int start, int count, int after) {}
 				@Override public void afterTextChanged(Editable s) {}
 			});
+			input.addOnAttachStateChangeListener(new View.OnAttachStateChangeListener(){
+				@Override
+				public void onViewAttachedToWindow(@NonNull View view){}
 
-			FrameLayout.LayoutParams params=new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT, Gravity.START);
+				@Override
-			int pad=forReaction ? 0 : V.dp(36 + 16);
+				public void onViewDetachedFromWindow(@NonNull View view){
-			params.setMargins(pad, V.dp(8), pad, V.dp(8));
+					input.getText().clear();
-			bottomPanel.addView(input, params);
 				}
+			});
+			topPanel.addView(input);
+
+		}else{ // in compose fragment
+			FrameLayout bottomPanel=new FrameLayout(activity);
+			bottomPanel.setPadding(V.dp(16), V.dp(8), V.dp(16), V.dp(8));
+			bottomPanel.setBackgroundResource(R.drawable.bg_m3_surface2);
+			ll.addView(bottomPanel, new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
 
-		if(!forReaction){
 			ImageButton hideKeyboard=new ImageButton(activity);
 			hideKeyboard.setImageResource(R.drawable.ic_fluent_keyboard_dock_24_regular);
 			hideKeyboard.setImageTintList(ColorStateList.valueOf(UiUtils.getThemeColor(activity, R.attr.colorM3OnSurfaceVariant)));
@@ -207,13 +219,16 @@ public class CustomEmojiPopupKeyboard extends PopupKeyboard{
 		}
 	}
 
-	private class SingleCategoryAdapter extends UsableRecyclerView.Adapter<RecyclerView.ViewHolder> implements ImageLoaderRecyclerAdapter{
+	private class SingleCategoryAdapter extends UsableRecyclerView.Adapter<RecyclerView.ViewHolder> implements ImageLoaderRecyclerAdapter, Filterable{
-		private final EmojiCategory category;
+		private EmojiCategory category;
-		private final List<ImageLoaderRequest> requests;
+
+		private final EmojiCategory originalCategory;
+		private List<ImageLoaderRequest> requests;
 
 		public SingleCategoryAdapter(EmojiCategory category){
 			super(imgLoader);
 			this.category=category;
+			this.originalCategory=new EmojiCategory(category);
 			requests=category.emojis.stream().map(e->new UrlImageLoaderRequest(e.getUrl(playGifs), V.dp(24), V.dp(24))).collect(Collectors.toList());
 		}
 
@@ -225,17 +240,22 @@ public class CustomEmojiPopupKeyboard extends PopupKeyboard{
 
 		@Override
 		public void onBindViewHolder(RecyclerView.ViewHolder holder, int position){
+			if(category.emojis.size() == 0) {
+				holder.itemView.setVisibility(View.GONE);
+			}
 			if(holder instanceof EmojiViewHolder evh){
 				evh.bind(category.emojis.get(position-1));
 				evh.positionWithinCategory=position-1;
 			}else if(holder instanceof SectionHeaderViewHolder shvh){
 				shvh.bind(TextUtils.isEmpty(category.title) ? domain : category.title);
 			}
+
 			super.onBindViewHolder(holder, position);
 		}
 
 		@Override
 		public int getItemCount(){
+			if(category.emojis.size() == 0) return 0;
 			return category.emojis.size()+1;
 		}
 
@@ -253,6 +273,39 @@ public class CustomEmojiPopupKeyboard extends PopupKeyboard{
 		public ImageLoaderRequest getImageRequest(int position, int image){
 			return requests.get(position-1);
 		}
+
+		@Override
+		public Filter getFilter(){
+			return emojiFilter;
+		}
+		private final Filter emojiFilter = new Filter(){
+			@Override
+			protected FilterResults performFiltering(CharSequence charSequence){
+				List<Emoji> filteredEmoji=new ArrayList<>();
+				String search=charSequence.toString().toLowerCase().trim();
+
+				if(charSequence==null || charSequence.length()==0){
+					filteredEmoji.addAll(originalCategory.emojis);
+				}else{
+					for(Emoji emoji : originalCategory.emojis){
+						if(emoji.shortcode.toLowerCase().contains(search)){
+							filteredEmoji.add(emoji);
+						}
+					}
+
+				}
+				FilterResults results=new FilterResults();
+				results.values=filteredEmoji;
+				return results;
+			}
+			@Override
+			protected void publishResults(CharSequence charSequence, FilterResults filterResults){
+				category.emojis.clear();
+				category.emojis.addAll((List) filterResults.values);
+				requests=category.emojis.stream().map(e->new UrlImageLoaderRequest(e.getUrl(playGifs), V.dp(24), V.dp(24))).collect(Collectors.toList());
+				notifyDataSetChanged();
+			}
+		};
 	}
 
 	private class SectionHeaderViewHolder extends BindableViewHolder<String> implements StickyHeadersOverlay.HeaderViewHolder{

mastodon/src/main/res/values/strings_sk.xml

@@ -364,7 +364,7 @@
     </plurals>
     <string name="sk_button_react">React with emoji</string>
 	<string name="sk_enter_emoji_toast">Please type an emoji</string>
-    <string name="sk_enter_emoji_hint">Type to react with an emoji</string>
+    <string name="sk_enter_emoji_hint">Type an emoji or search custom emoji</string>
     <string name="sk_mute_label">Duration</string>
     <string name="sk_duration_indefinite">Indefinite</string>
     <string name="sk_duration_minutes_5">5 minutes</string>