[TextField] Correctly calculate hint text offset

We changes letter spacing during expanding/collapsing animations, which causes us use letter spacing during animation while calculating final expanded/collapsed offset instead of final letter spacing. This in turn causes hints be drawn at the wrong positions. Uses final letter spacing during calculating offset instead to fix the problem. Resolves #2277 PiperOrigin-RevId: 408904991
material-components · Nov 10, 2021 · 34cce18 · 34cce18
1 parent f898ba8
commit 34cce18
Showing 1 changed file with 17 additions and 14 deletions.
diff --git a/lib/java/com/google/android/material/internal/CollapsingTextHelper.java b/lib/java/com/google/android/material/internal/CollapsingTextHelper.java
@@ -665,12 +665,8 @@ private void calculateBaseOffsets(boolean forceRecalculate) {
           TextUtils.ellipsize(textToDraw, textPaint, textLayout.getWidth(), TruncateAt.END);
     }
     if (textToDrawCollapsed != null) {
-      TextPaint collapsedTextPaint = new TextPaint(textPaint);
-      if (VERSION.SDK_INT >= VERSION_CODES.LOLLIPOP) {
-        collapsedTextPaint.setLetterSpacing(collapsedLetterSpacing);
-      }
-      collapsedTextWidth =
-          collapsedTextPaint.measureText(textToDrawCollapsed, 0, textToDrawCollapsed.length());
+      getTextPaintCollapsed(tmpPaint);
+      collapsedTextWidth = measureTextWidth(tmpPaint, textToDrawCollapsed);
     } else {
       collapsedTextWidth = 0;
     }
@@ -708,12 +704,15 @@ private void calculateBaseOffsets(boolean forceRecalculate) {
 
     calculateUsingTextSize(expandedTextSize, forceRecalculate);
     float expandedTextHeight = textLayout != null ? textLayout.getHeight() : 0;
+    float expandedTextWidth = 0;
+    if (textLayout != null && maxLines > 1) {
+      expandedTextWidth = textLayout.getWidth();
+    } else if (textToDraw != null) {
+      getTextPaintExpanded(tmpPaint);
+      expandedTextWidth = measureTextWidth(tmpPaint, textToDraw);
+    }
     expandedLineCount = textLayout != null ? textLayout.getLineCount() : 0;
 
-    float measuredWidth = textToDraw != null
-        ? textPaint.measureText(textToDraw, 0, textToDraw.length()) : 0;
-    float width = textLayout != null && maxLines > 1 ? textLayout.getWidth() : measuredWidth;
-
     final int expandedAbsGravity =
         GravityCompat.getAbsoluteGravity(
             expandedTextGravity,
@@ -734,10 +733,10 @@ private void calculateBaseOffsets(boolean forceRecalculate) {
 
     switch (expandedAbsGravity & GravityCompat.RELATIVE_HORIZONTAL_GRAVITY_MASK) {
       case Gravity.CENTER_HORIZONTAL:
-        expandedDrawX = expandedBounds.centerX() - (width / 2);
+        expandedDrawX = expandedBounds.centerX() - (expandedTextWidth / 2);
         break;
       case Gravity.RIGHT:
-        expandedDrawX = expandedBounds.right - width;
+        expandedDrawX = expandedBounds.right - expandedTextWidth;
         break;
       case Gravity.LEFT:
       default:
@@ -751,6 +750,10 @@ private void calculateBaseOffsets(boolean forceRecalculate) {
     setInterpolatedTextSize(currentTextSize);
   }
 
+  private float measureTextWidth(TextPaint textPaint, CharSequence textToDraw) {
+    return textPaint.measureText(textToDraw, 0, textToDraw.length());
+  }
+
   private void interpolateBounds(float fraction) {
     if (fadeModeEnabled) {
       currentBounds.set(fraction < fadeModeThresholdFraction ? expandedBounds : collapsedBounds);
@@ -787,9 +790,9 @@ public void draw(@NonNull Canvas canvas) {
       if (DEBUG_DRAW) {
         // Just a debug tool, which drawn a magenta rect in the text bounds
         canvas.drawRect(
-            currentBounds.left,
+            x,
             y,
-            currentBounds.right,
+            x + textLayout.getWidth() * scale,
             y + textLayout.getHeight() * scale,
             DEBUG_DRAW_PAINT);
       }