Support two line text in AllApps/OnDeviceSearch w/ feature flag

Made separate feature flag for on device search
Add unit test to test twoLine string
- Unit tests for testing newStringThatShouldSupportTwoLineText() in BubbleTextView.java. This class tests a couple of strings
and uses the getLineCount() to determine if the test passes. Verifying with getLineCount() is sufficient since BubbleTextView can only be in one line or two lines,
and this is enough to ensure whether the string should be specifically wrapped onto the second line and to ensure truncation.

bug: 201388851
test: presubmit, ran locally on big and small device, before: https://screenshot.googleplex.com/3Q6pwveFDZqxDXL (ORIGINAL TWO LINE TEXT)
after:  https://screenshot.googleplex.com/7pkwUto6HGzMYoT

Change-Id: I93e6ed179e1081d5cdffc6db9c7ae34de8021c24

src/com/android/launcher3/BubbleTextView.java

@@ -52,8 +52,10 @@ import android.widget.TextView;
 
 import androidx.annotation.Nullable;
 import androidx.annotation.UiThread;
+import androidx.annotation.VisibleForTesting;
 
 import com.android.launcher3.accessibility.BaseAccessibilityDelegate;
+import com.android.launcher3.config.FeatureFlags;
 import com.android.launcher3.dot.DotInfo;
 import com.android.launcher3.dragndrop.DragOptions.PreDragCondition;
 import com.android.launcher3.dragndrop.DraggableView;
@@ -71,6 +73,8 @@ import com.android.launcher3.model.data.ItemInfoWithIcon;
 import com.android.launcher3.model.data.WorkspaceItemInfo;
 import com.android.launcher3.popup.PopupContainerWithArrow;
 import com.android.launcher3.util.MultiTranslateDelegate;
+import com.android.launcher3.search.StringMatcherUtility;
+import com.android.launcher3.util.IntArray;
 import com.android.launcher3.util.SafeCloseable;
 import com.android.launcher3.util.ShortcutUtil;
 import com.android.launcher3.views.ActivityContext;
@@ -97,11 +101,19 @@ public class BubbleTextView extends TextView implements ItemInfoUpdateReceiver,
 
     private static final float MIN_LETTER_SPACING = -0.05f;
     private static final int MAX_SEARCH_LOOP_COUNT = 20;
+    private static final Character NEW_LINE = '\n';
+    private static final String EMPTY = "";
+    private static final StringMatcherUtility.StringMatcher MATCHER =
+            StringMatcherUtility.StringMatcher.getInstance();
 
     private static final int[] STATE_PRESSED = new int[]{android.R.attr.state_pressed};
 
     private float mScaleForReorderBounce = 1f;
 
+    private IntArray mBreakPointsIntArray;
+    private CharSequence mLastOriginalText;
+    private CharSequence mLastModifiedText;
+
     private static final Property<BubbleTextView, Float> DOT_SCALE_PROPERTY
             = new Property<BubbleTextView, Float>(Float.TYPE, "dotScale") {
         @Override
@@ -134,7 +146,7 @@ public class BubbleTextView extends TextView implements ItemInfoUpdateReceiver,
     private FastBitmapDrawable mIcon;
     private boolean mCenterVertically;
 
-    protected final int mDisplay;
+    protected int mDisplay;
 
     private final CheckLongPressHelper mLongPressHelper;
 
@@ -255,6 +267,8 @@ public class BubbleTextView extends TextView implements ItemInfoUpdateReceiver,
         mDotParams.scale = 0f;
         mForceHideDot = false;
         setBackground(null);
+        setSingleLine(true);
+        setMaxLines(1);
 
         setTag(null);
         if (mIconLoadRequest != null) {
@@ -382,8 +396,15 @@ public class BubbleTextView extends TextView implements ItemInfoUpdateReceiver,
     }
 
     @UiThread
-    private void applyLabel(ItemInfoWithIcon info) {
-        setText(info.title);
+    @VisibleForTesting
+    public void applyLabel(ItemInfoWithIcon info) {
+        CharSequence label = info.title;
+        if (label != null) {
+            mLastOriginalText = label;
+            mLastModifiedText = mLastOriginalText;
+            mBreakPointsIntArray = StringMatcherUtility.getListOfBreakpoints(label, MATCHER);
+            setText(label);
+        }
         if (info.contentDescription != null) {
             setContentDescription(info.isDisabled()
                     ? getContext().getString(R.string.disabled_app_label, info.contentDescription)
@@ -391,6 +412,12 @@ public class BubbleTextView extends TextView implements ItemInfoUpdateReceiver,
         }
     }
 
+    /** This is used for testing to forcefully set the display to ALL_APPS */
+    @VisibleForTesting
+    public void setDisplayAllApps() {
+        mDisplay = DISPLAY_ALL_APPS;
+    }
+
     /**
      * Overrides the default long press timeout.
      */
@@ -637,6 +664,27 @@ public class BubbleTextView extends TextView implements ItemInfoUpdateReceiver,
             setPadding(getPaddingLeft(), (height - cellHeightPx) / 2, getPaddingRight(),
                     getPaddingBottom());
         }
+        // only apply two line for all_apps
+        if (FeatureFlags.ENABLE_TWOLINE_ALLAPPS.get() && (mLastOriginalText != null)
+                && (mDisplay == DISPLAY_ALL_APPS)) {
+            CharSequence modifiedString = modifyTitleToSupportMultiLine(
+                    MeasureSpec.getSize(widthMeasureSpec) - getCompoundPaddingLeft()
+                            - getCompoundPaddingRight(),
+                    mLastOriginalText,
+                    getPaint(), mBreakPointsIntArray);
+            if (!TextUtils.equals(modifiedString, mLastModifiedText)) {
+                mLastModifiedText = modifiedString;
+                setText(modifiedString);
+                // if text contains NEW_LINE, set max lines to 2
+                if (TextUtils.indexOf(modifiedString, NEW_LINE) != -1) {
+                    setSingleLine(false);
+                    setMaxLines(2);
+                } else {
+                    setSingleLine(true);
+                    setMaxLines(1);
+                }
+            }
+        }
         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
     }
 
@@ -697,6 +745,73 @@ public class BubbleTextView extends TextView implements ItemInfoUpdateReceiver,
         return ObjectAnimator.ofFloat(this, TEXT_ALPHA_PROPERTY, toAlpha);
     }
 
+    /**
+     * Generate a new string that will support two line text depending on the current string.
+     * This method calculates the limited width of a text view and creates a string to fit as
+     * many words as it can until the limit is reached. Once the limit is reached, we decide to
+     * either return the original title or continue on a new line. How to get the new string is by
+     * iterating through the list of break points and determining if the strings between the break
+     * points can fit within the line it is in.
+     *  Example assuming each character takes up one spot:
+     *  title = "Battery Stats", breakpoint = [6], stringPtr = 0, limitedWidth = 7
+     *  We get the current word -> from sublist(0, breakpoint[i]+1) so sublist (0,7) -> Battery,
+     *  now stringPtr = 7 then from sublist(7) the current string is " Stats" and the runningWidth
+     *  at this point exceeds limitedWidth and so we put " Stats" onto the next line (after checking
+     *  if the first char is a SPACE, we trim to append "Stats". So resulting string would be
+     *  "Battery\nStats"
+     */
+    public static CharSequence modifyTitleToSupportMultiLine(int limitedWidth, CharSequence title,
+            TextPaint paint, IntArray breakPoints) {
+        // current title is less than the width allowed so we can just skip
+        if (title == null || paint.measureText(title, 0, title.length()) <= limitedWidth) {
+            return title;
+        }
+        float currentWordWidth, runningWidth = 0;
+        CharSequence currentWord;
+        StringBuilder newString = new StringBuilder();
+        int stringPtr = 0;
+        for (int i = 0; i < breakPoints.size()+1; i++) {
+            if (i < breakPoints.size()) {
+                currentWord = title.subSequence(stringPtr, breakPoints.get(i)+1);
+            } else {
+                // last word from recent breakpoint until the end of the string
+                currentWord = title.subSequence(stringPtr, title.length());
+            }
+            currentWordWidth = paint.measureText(currentWord,0, currentWord.length());
+            runningWidth += currentWordWidth;
+            if (runningWidth <= limitedWidth) {
+                newString.append(currentWord);
+            } else {
+                // there is no more space
+                if (i == 0) {
+                    // if the first words exceeds width, just return as the first line will ellipse
+                    return title;
+                } else {
+                    // If putting word onto a new line, make sure there is no space or new line
+                    // character in the beginning of the current word and just put in the rest of
+                    // the characters.
+                    CharSequence lastCharacters = title.subSequence(stringPtr, title.length());
+                    int beginningLetterType =
+                            Character.getType(Character.codePointAt(lastCharacters,0));
+                    if (beginningLetterType == Character.SPACE_SEPARATOR
+                            || beginningLetterType == Character.LINE_SEPARATOR) {
+                        lastCharacters = lastCharacters.length() > 1
+                                ? lastCharacters.subSequence(1, lastCharacters.length())
+                                : EMPTY;
+                    }
+                    newString.append(NEW_LINE).append(lastCharacters);
+                    return newString.toString();
+                }
+            }
+            if (i >= breakPoints.size()) {
+                // no need to look forward into the string if we've already finished processing
+                break;
+            }
+            stringPtr = breakPoints.get(i)+1;
+        }
+        return newString.toString();
+    }
+
     @Override
     public void cancelLongPress() {
         super.cancelLongPress();