Add hiding and showing of modifier keys

Author: unverbraucht

lib/build.gradle

@@ -2,7 +2,7 @@ apply plugin: 'com.android.library'
 
 ext.versionMajor = 3 // API Changes, adding big new feature, redesign the App
 ext.versionMinor = 0 // New features in a backwards-compatible manner
-ext.versionPatch = 2 // Backwards-compatible bug fixes
+ext.versionPatch = 3 // Backwards-compatible bug fixes
 ext.versionClassifier = null // Pre-releases (alpha, beta, rc, SNAPSHOT...)
 
 android {

lib/src/main/java/com/davidmiguel/numberkeyboard/NumberKeyboard.java

@@ -140,6 +140,22 @@ public void showRightAuxButton() {
         rightAuxBtn.setVisibility(VISIBLE);
     }
 
+    /**
+     * Hides a modifier button.
+     * @param modifierIdx index of modifier key
+     */
+    public void hideModifierButton(final int modifierIdx) {
+        modifierKeys.get(modifierIdx).setVisibility(GONE);
+    }
+
+    /**
+     * Shows a modifier button.
+     * @param modifierIdx index of modifier key
+     */
+    public void showModifierButton(final int modifierIdx) {
+        modifierKeys.get(modifierIdx).setVisibility(VISIBLE);
+    }
+
     /**
      * Sets left auxiliary button to send the IME action if EditText has been connected via
      * {@link #setEditText(EditText) setEditText}. Note that setting this to false