Fallback logic for button shape update logic for lollipop

Author: vicmns

lib/java/com/google/android/material/button/MaterialButtonHelper.java

@@ -16,10 +16,6 @@
 
 package com.google.android.material.button;
 
-import com.google.android.material.R;
-
-import static androidx.annotation.RestrictTo.Scope.LIBRARY_GROUP;
-
 import android.content.Context;
 import android.content.res.ColorStateList;
 import android.content.res.TypedArray;
@@ -31,12 +27,15 @@
 import android.graphics.drawable.RippleDrawable;
 import android.os.Build.VERSION;
 import android.os.Build.VERSION_CODES;
-import androidx.core.graphics.drawable.DrawableCompat;
-import androidx.core.view.ViewCompat;
+
 import androidx.annotation.Dimension;
 import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
 import androidx.annotation.RestrictTo;
+import androidx.core.graphics.drawable.DrawableCompat;
+import androidx.core.view.ViewCompat;
+
+import com.google.android.material.R;
 import com.google.android.material.color.MaterialColors;
 import com.google.android.material.internal.ViewUtils;
 import com.google.android.material.resources.MaterialResources;
@@ -46,6 +45,8 @@
 import com.google.android.material.shape.ShapeAppearanceModel;
 import com.google.android.material.shape.Shapeable;
 
+import static androidx.annotation.RestrictTo.Scope.LIBRARY_GROUP;
+
 /** @hide */
 @RestrictTo(LIBRARY_GROUP)
 class MaterialButtonHelper {
@@ -359,14 +360,20 @@ private MaterialShapeDrawable getSurfaceColorStrokeDrawable() {
   }
 
   private void updateButtonShape(@NonNull ShapeAppearanceModel shapeAppearanceModel) {
-    if (getMaterialShapeDrawable() != null) {
-      getMaterialShapeDrawable().setShapeAppearanceModel(shapeAppearanceModel);
-    }
-    if (getSurfaceColorStrokeDrawable() != null) {
-      getSurfaceColorStrokeDrawable().setShapeAppearanceModel(shapeAppearanceModel);
-    }
-    if (getMaskDrawable() != null) {
-      getMaskDrawable().setShapeAppearanceModel(shapeAppearanceModel);
+    if (IS_LOLLIPOP) {
+      // There seems to be a bug to drawables that is affecting Lollipop, since invalidation is not
+      // changing an existing drawable shape. This is a fallback
+      updateBackground();
+    } else {
+      if (getMaterialShapeDrawable() != null) {
+        getMaterialShapeDrawable().setShapeAppearanceModel(shapeAppearanceModel);
+      }
+      if (getSurfaceColorStrokeDrawable() != null) {
+        getSurfaceColorStrokeDrawable().setShapeAppearanceModel(shapeAppearanceModel);
+      }
+      if (getMaskDrawable() != null) {
+        getMaskDrawable().setShapeAppearanceModel(shapeAppearanceModel);
+      }
     }
   }