Visualization for parse trees on Android

src/ui/android/res/layout/alternative_item.xml

@@ -12,16 +12,18 @@
         android:paddingRight="5dp" />
   
     <TextView
-        android:id="@+id/lexical_desc"
+        android:id="@+id/alternative_desc"
         android:layout_width="fill_parent"
         android:layout_height="wrap_content"
         android:layout_toRightOf="@id/arrow"
         android:paddingLeft="10dp"
         android:textSize="25sp"/>
     
-    <WebView
+	<org.grammaticalframework.ui.android.ParseTreeView
-        android:id="@+id/lexical_inflection"
+    	android:id="@+id/desc_details"
-        android:layout_width="wrap_content"
+    	android:layout_width="wrap_content"
-        android:layout_height="wrap_content"
+    	android:layout_height="wrap_content"
-        android:layout_below="@id/lexical_desc"/>
+    	android:layout_below="@id/alternative_desc"
+        android:textSize="25sp"
+    	/>
 </RelativeLayout>

src/ui/android/res/layout/lexical_item.xml

@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="utf-8"?>
+<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="fill_parent"
+    android:layout_height="fill_parent" >
+    <ImageView
+        android:id="@+id/arrow"
+        android:layout_width="30dp"
+        android:layout_height="30dp"
+        android:contentDescription="@string/open_image"
+        android:src="@drawable/open_arrow"
+        android:paddingLeft="10dp"
+        android:paddingRight="5dp" />
+  
+    <TextView
+        android:id="@+id/lexical_desc"
+        android:layout_width="fill_parent"
+        android:layout_height="wrap_content"
+        android:layout_toRightOf="@id/arrow"
+        android:paddingLeft="10dp"
+        android:textSize="25sp"/>
+    
+    <WebView
+        android:id="@+id/desc_details"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:layout_below="@id/lexical_desc"/>
+</RelativeLayout>

src/ui/android/src/org/grammaticalframework/ui/android/AlternativesActivity.java

@@ -103,8 +103,8 @@ public class AlternativesActivity extends ListActivity {
 		ImageView arrow = (ImageView) expandedView.findViewById(R.id.arrow);
 		arrow.setImageResource(R.drawable.open_arrow);
 
-		WebView inflectionView = (WebView) expandedView.findViewById(R.id.lexical_inflection);
+		View view = (View) expandedView.findViewById(R.id.desc_details);
-		((RelativeLayout) expandedView).removeView(inflectionView);
+		((RelativeLayout) expandedView).removeView(view);
 
 		expandedView = null;
 	}
@@ -117,10 +117,10 @@ public class AlternativesActivity extends ListActivity {
 		ImageView arrow = (ImageView) view.findViewById(R.id.arrow);
 		arrow.setImageResource(R.drawable.close_arrow);
 		
-		WebView inflectionView = (WebView) view.findViewById(R.id.lexical_inflection);
+		WebView inflectionView = (WebView) view.findViewById(R.id.desc_details);
 		if (inflectionView == null) {
 			inflectionView = new WebView(this);
-			inflectionView.setId(R.id.lexical_inflection);
+			inflectionView.setId(R.id.desc_details);
 			RelativeLayout.LayoutParams params = 
 					new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
 			params.addRule(RelativeLayout.BELOW, R.id.lexical_desc);
@@ -136,18 +136,18 @@ public class AlternativesActivity extends ListActivity {
 		ImageView arrow = (ImageView) view.findViewById(R.id.arrow);
 		arrow.setImageResource(R.drawable.close_arrow);
 		
-		WebView inflectionView = (WebView) view.findViewById(R.id.lexical_inflection);
+		ParseTreeView parseView = (ParseTreeView) view.findViewById(R.id.desc_details);
-		if (inflectionView == null) {
+		if (parseView == null) {
-			inflectionView = new WebView(this);
+			parseView = new ParseTreeView(this);
-			inflectionView.setId(R.id.lexical_inflection);
+			parseView.setId(R.id.desc_details);
 			RelativeLayout.LayoutParams params = 
 					new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
-			params.addRule(RelativeLayout.BELOW, R.id.lexical_desc);
+			params.addRule(RelativeLayout.BELOW, R.id.alternative_desc);
-			((RelativeLayout) view).addView(inflectionView, params);
+			((RelativeLayout) view).addView(parseView, params);
 		}
 
-		String content = String.format("[%.4f] %s", ep.getProb(), ep.getExpr());
+		Object[] brackets = mTranslator.bracketedLinearize(ep.getExpr());
-		inflectionView.loadData(content, "text/plain; charset=UTF-8", null);
+		parseView.setBrackets(brackets);
 
 		expandedView = view;
 	}
@@ -160,16 +160,16 @@ public class AlternativesActivity extends ListActivity {
     	public View getView(int position, View convertView, ViewGroup parent) {
 			Object item = getItem(position);
 
-			if (convertView == null) {
-				LayoutInflater inflater = (LayoutInflater) 
-						getContext().getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
-	            convertView = inflater.inflate(R.layout.alternative_item, null);
-	        }
-
-	        TextView descView = (TextView)
-	        	convertView.findViewById(R.id.lexical_desc);
-
 			if (item instanceof MorphoAnalysis) {
+				if (convertView == null) {
+					LayoutInflater inflater = (LayoutInflater) 
+							getContext().getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
+		            convertView = inflater.inflate(R.layout.lexical_item, null);
+		        }
+
+		        TextView descView = (TextView)
+		        	convertView.findViewById(R.id.lexical_desc);
+
 				final String lemma = ((MorphoAnalysis) item).getLemma();
 
 		    	String phrase = mTranslator.generateLexiconEntry(lemma);
@@ -188,55 +188,62 @@ public class AlternativesActivity extends ListActivity {
 						}
 					}
 				});
-			} else {
+			} else if (item instanceof ExprProb) {
-				if (item instanceof ExprProb) {
+				final ExprProb ep = (ExprProb) item;
-					final ExprProb ep = (ExprProb) item;
+	
-		
+				if (convertView == null) {
-			    	String phrase = mTranslator.linearize(ep.getExpr());
+					LayoutInflater inflater = (LayoutInflater) 
+							getContext().getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
+		            convertView = inflater.inflate(R.layout.alternative_item, null);
+		        }
 
-			    	// parse by words, marked by %, darkest red color
+		        TextView descView = (TextView)
-			    	if (phrase.charAt(0) == '%') {
+		        	convertView.findViewById(R.id.alternative_desc);
-			    		descView.setBackgroundDrawable(getResources().getDrawable(R.drawable.second_person_worst_utterance_bg));
-			    		phrase = phrase.substring(2);
-			    	}
 
-			    	// parse by chunks, marked by *, red color
+		    	String phrase = mTranslator.linearize(ep.getExpr());
-			    	else if (phrase.charAt(0) == '*') {
-			    		descView.setBackgroundDrawable(getResources().getDrawable(R.drawable.second_person_chunk_utterance_bg));
-			    		phrase = phrase.substring(2);
-			    	}
 
-			    	// parse error or unknown translations (in []) present, darkest red color
+		    	// parse by words, marked by %, darkest red color
-			    	else if (phrase.contains("parse error:") || phrase.contains("[")) {
+		    	if (phrase.charAt(0) == '%') {
-			    		descView.setBackgroundDrawable(getResources().getDrawable(R.drawable.second_person_worst_utterance_bg));
+		    		descView.setBackgroundDrawable(getResources().getDrawable(R.drawable.second_person_worst_utterance_bg));
-			    	}
+		    		phrase = phrase.substring(2);
+		    	}
 
-			    	// parse by domain grammar, marked by +, green color
+		    	// parse by chunks, marked by *, red color
-			    	else if (phrase.charAt(0) == '+') {
+		    	else if (phrase.charAt(0) == '*') {
-			    		descView.setBackgroundDrawable(getResources().getDrawable(R.drawable.second_person_best_utterance_bg));
+		    		descView.setBackgroundDrawable(getResources().getDrawable(R.drawable.second_person_chunk_utterance_bg));
-			    		phrase = phrase.substring(2);
+		    		phrase = phrase.substring(2);
-			    	}
+		    	}
-			    	
-			    	else {
-			    		descView.setBackgroundDrawable(getResources().getDrawable(R.drawable.second_person_utterance_bg));
-			    	}
 
-			        descView.setText(phrase);
+		    	// parse error or unknown translations (in []) present, darkest red color
+		    	else if (phrase.contains("parse error:") || phrase.contains("[")) {
+		    		descView.setBackgroundDrawable(getResources().getDrawable(R.drawable.second_person_worst_utterance_bg));
+		    	}
 
-			        convertView.setOnClickListener(new OnClickListener() {
+		    	// parse by domain grammar, marked by +, green color
-						@Override
+		    	else if (phrase.charAt(0) == '+') {
-						public void onClick(View view) {
+		    		descView.setBackgroundDrawable(getResources().getDrawable(R.drawable.second_person_best_utterance_bg));
-							if (expandedView == view)
+		    		phrase = phrase.substring(2);
-								collapse();
+		    	}
-							else if (expandedView == null)
+		    	
-								expandExpr(view, ep);
+		    	else {
-							else {
+		    		descView.setBackgroundDrawable(getResources().getDrawable(R.drawable.second_person_utterance_bg));
-								collapse();
+		    	}
-								expandExpr(view, ep);
+
-							}
+		        descView.setText(phrase);
+
+		        convertView.setOnClickListener(new OnClickListener() {
+					@Override
+					public void onClick(View view) {
+						if (expandedView == view)
+							collapse();
+						else if (expandedView == null)
+							expandExpr(view, ep);
+						else {
+							collapse();
+							expandExpr(view, ep);
 						}
-					});
+					}
-				}
+				});
 			}
 
 			return convertView;

src/ui/android/src/org/grammaticalframework/ui/android/ParseTreeView.java

@@ -0,0 +1,221 @@
+package org.grammaticalframework.ui.android;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import android.content.Context;
+import android.graphics.Canvas;
+import android.graphics.Paint;
+import android.graphics.PointF;
+import android.graphics.Rect;
+import android.util.AttributeSet;
+import android.util.Pair;
+import android.util.SparseArray;
+import android.view.View;
+import org.grammaticalframework.pgf.Bracket;
+
+
+public class ParseTreeView extends View {
+	private static final float SISTER_SKIP = 25;
+	private static final float PARENT_SKIP = 0.5f;
+	private static final float ABOVE_LINE_SKIP = 0.1f;
+	private static final float BELOW_LINE_SKIP = 0.1f;
+
+	private Paint paint;
+	private Object[] brackets;
+
+	public ParseTreeView(Context context) {
+		super(context);
+		initialize();
+	}
+	
+	public ParseTreeView(Context context, AttributeSet attrs) {
+		super(context, attrs);
+		initialize();
+	}
+	
+	private void initialize() {
+		paint = new Paint();
+		paint.setTextSize(60);
+		brackets = null;
+	}
+	
+	public Object[] getBrackets() {
+		return brackets;
+	}
+
+	public void setBrackets(Object[] brackets) {
+		this.brackets = brackets; 
+	}
+
+	static class MeasureResult {
+		float width = 0.0f;
+		float height = 0.0f;
+		float nodeTab = 0.0f;
+		float nodeCenter = 0.0f;
+		float childTab = 0.0f;
+		float localWidth = 0.0f;
+		float localHeight = 0.0f;
+	}
+
+	private MeasureResult mr = new MeasureResult();
+	private SparseArray<PointF> coords = new SparseArray<PointF>();
+
+	private void measureTree(Object o, PointF zeroPoint) {
+		if (o instanceof Bracket) {
+			Bracket bracket = (Bracket) o;
+
+			Rect bounds = new Rect();
+			paint.getTextBounds(bracket.cat,0,bracket.cat.length(),bounds);
+			float localWidth  = bounds.width();
+			float localHeight = bounds.height();
+			float layerHeight = localHeight * (1.0f + BELOW_LINE_SKIP + ABOVE_LINE_SKIP + PARENT_SKIP);
+
+			PointF local = coords.get(bracket.fid);
+			if (local == null) {
+				if (zeroPoint != null)
+					coords.put(bracket.fid, zeroPoint);
+			} else {
+				localWidth = 0; 
+			}
+
+			float subWidth = 0.0f;
+			float subHeight = 0.0f;
+			float nodeCenter = 0.0f;
+			for (int i = 0; i < bracket.children.length; i++) {
+				measureTree(bracket.children[i], zeroPoint);
+				
+				if (i == 0) {
+					nodeCenter += (subWidth + mr.nodeCenter) / 2.0;
+				}
+				if (i == bracket.children.length - 1) {
+					nodeCenter += (subWidth + mr.nodeCenter) / 2.0;
+				}
+	
+				subWidth += mr.width;
+				if (i < bracket.children.length - 1) {
+					subWidth += SISTER_SKIP;
+				}
+	
+				if (subHeight < mr.height)
+					subHeight = mr.height;
+			}
+			float localLeft = localWidth / 2.0f;
+			float subLeft = nodeCenter;
+			float totalLeft = Math.max(localLeft, subLeft);
+			float localRight = localWidth / 2.0f;
+			float subRight = subWidth - nodeCenter;
+			float totalRight = Math.max(localRight, subRight);
+			mr.width = totalLeft + totalRight;
+			mr.height = layerHeight + subHeight;  
+			mr.childTab = totalLeft - subLeft;
+			mr.nodeTab = totalLeft - localLeft;
+			mr.nodeCenter = nodeCenter + mr.childTab;
+			mr.localWidth = localWidth;
+			mr.localHeight = localHeight;			
+		} else {
+			String word = o.toString();
+
+			Rect bounds = new Rect();
+			paint.getTextBounds(word,0,word.length(),bounds);
+			mr.width  = bounds.width();
+			mr.height = bounds.height();
+			mr.nodeTab = 0.0f;
+			mr.nodeCenter = bounds.width() / 2.0f;
+			mr.childTab = 0.0f;
+			mr.localWidth = bounds.width();
+			mr.localHeight = bounds.height();
+		}
+	}
+
+	@Override
+	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+		if (brackets == null) {
+			setMeasuredDimension(0, 0);
+			return;
+		}
+
+		float width = 0.0f;
+		float height = 0.0f;
+		PointF zeroPoint = new PointF();
+		for (int i = 0; i < brackets.length; i++) {
+			measureTree(brackets[i], zeroPoint);
+
+			width += mr.width;
+			if (i < brackets.length - 1) {
+				width += SISTER_SKIP;
+			}
+
+			if (height < mr.height)
+				height = mr.height;
+		}
+
+		width  += 10;
+		height += 10;
+
+		int w = getPaddingLeft() + (int) width  + getPaddingRight();
+		int h = getPaddingTop()  + (int) height + getPaddingBottom();
+
+		setMeasuredDimension(w, h);
+	}
+
+	private void drawTree(Canvas canvas,
+			              float x, float y, float bottom, PointF parentPoint, 
+			              Object o) {
+		if (o instanceof Bracket) {
+			Bracket bracket = (Bracket) o;
+
+			PointF lineStart = coords.get(bracket.fid);
+			if (lineStart == null) {
+				lineStart = new PointF(x + mr.nodeCenter, y + mr.localHeight * (1.0f + BELOW_LINE_SKIP));
+				coords.put(bracket.fid, lineStart);
+
+				if (parentPoint != null) {
+					float lineEndX = x + mr.nodeCenter;
+					float lineEndY = y;
+					canvas.drawLine(parentPoint.x, parentPoint.y, lineEndX, lineEndY, paint);
+				}
+
+				canvas.drawText(bracket.cat, x+mr.nodeTab, y+mr.localHeight, paint);
+			}
+
+			float layerMultiplier = (1.0f + BELOW_LINE_SKIP + ABOVE_LINE_SKIP + PARENT_SKIP);
+			float layerHeight = mr.localHeight * layerMultiplier;
+			float childStartX = x + mr.childTab;
+			float childStartY = y + layerHeight;
+			for (int i = 0; i < bracket.children.length; i++) {
+				Object child = bracket.children[i];
+				measureTree(child, null);
+				float w = mr.width;
+				drawTree(canvas, childStartX, childStartY, bottom, lineStart, child);
+				childStartX += w + SISTER_SKIP;
+			}
+		} else  {
+			float lineEndX = x + mr.nodeCenter;
+			float lineEndY = bottom - mr.height;
+			canvas.drawLine(parentPoint.x, parentPoint.y, lineEndX, lineEndY, paint);
+			canvas.drawText(o.toString(), x, bottom, paint);
+		}
+	}
+
+	@Override
+	protected void onDraw (Canvas canvas) {
+		super.onDraw(canvas);
+		
+		if (brackets == null) {
+			return;
+		}
+
+		coords.clear();
+
+		float startX = getPaddingLeft();
+		for (int i = 0; i < brackets.length; i++) {
+			Object child = brackets[i];
+
+			measureTree(child, null);
+			float w = mr.width;
+			drawTree(canvas, startX, getPaddingTop(), getPaddingTop()+mr.height, null, child);
+			startX += w + SISTER_SKIP;
+		}
+	}
+}

src/ui/android/src/org/grammaticalframework/ui/android/Translator.java

@@ -340,6 +340,11 @@ public class Translator {
     	return targetLang.linearize(expr);
     }
 
+    public Object[] bracketedLinearize(Expr expr) {
+    	Concr targetLang = getTargetConcr();
+    	return targetLang.bracketedLinearize(expr);
+    }
+
     public String generateLexiconEntry(String lemma) {
         Concr sourceLang = getSourceConcr();
         Concr targetLang = getTargetConcr();