Fatal Exception: String can't be cast to Spannable

My app works greatly with the exception of a few devices. On one such device, I get a FATAL EXCEPTION in one of my activities. The error is java.lang.ClassCastException: java.lang.String cannot be cast to android.text.Spannable ... ... at android.widget.TextView.setEnabled(TextView.java:1432) STACK TRACE ``` 05-02 09:18:19.917: E/AndroidRuntime(20587): FATAL EXCEPTION: main 05-02 09:18:19.917: E/AndroidRuntime(20587): java.lang.ClassCastException: java.lang.String cannot be cast to android.text.Spannable 05-02 09:18:19.917: E/AndroidRuntime(20587): at android.widget.TextView.setEnabled(TextView.java:1432) 05-02 09:18:19.917: E/AndroidRuntime(20587): at com.myapp.android.menu.LoginFragment.checkIfAnyFieldIsEmpty(LoginFragment.java:512) 05-02 09:18:19.917: E/AndroidRuntime(20587): at com.myapp.android.menu.LoginFragment.onCreateView(LoginFragment.java:183) 05-02 09:18:19.917: E/AndroidRuntime(20587): at android.support.v4.app.Fragment.performCreateView(Fragment.java:1460) 05-02 09:18:19.917: E/AndroidRuntime(20587): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:911) 05-02 09:18:19.917: E/AndroidRuntime(20587): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088) 05-02 09:18:19.917: E/AndroidRuntime(20587): at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682) 05-02 09:18:19.917: E/AndroidRuntime(20587): at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444) 05-02 09:18:19.917: E/AndroidRuntime(20587): at android.support.v4.app.FragmentManagerImpl$1.run(FragmentManager.java:429) 05-02 09:18:19.917: E/AndroidRuntime(20587): at android.os.Handler.handleCallback(Handler.java:615) 05-02 09:18:19.917: E/AndroidRuntime(20587): at android.os.Handler.dispatchMessage(Handler.java:92) 05-02 09:18:19.917: E/AndroidRuntime(20587): at android.os.Looper.loop(Looper.java:137) 05-02 09:18:19.917: E/AndroidRuntime(20587): at android.app.ActivityThread.main(ActivityThread.java:4962) 05-02 09:18:19.917: E/AndroidRuntime(20587): at java.lang.reflect.Method.invokeNative(Native Method) 05-02 09:18:19.917: E/AndroidRuntime(20587): at java.lang.reflect.Method.invoke(Method.java:511) 05-02 09:18:19.917: E/AndroidRuntime(20587): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1004) 05-02 09:18:19.917: E/AndroidRuntime(20587): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:771) 05-02 09:18:19.917: E/AndroidRuntime(20587): at dalvik.system.NativeStart.main(Native Method) ``` Here are the snippets of code surrounding the error. XML LAYOUT CODE ``` <com.myapp.android.view.StyledButton android:id="@+id/login_sign_in" style="@style/button_blue" android:layout_width="fill_parent" android:layout_height="wrap_content" android:background="@drawable/state_list_login" android:textColor="@color/white" android:imeOptions="actionDone" android:padding="10dp" android:text="@string/sign_in" /> ``` CUSTOM BUTTON JAVA CODE ``` public class StyledButton extends Button { //variables private final String BOLD = "fonts/arial.ttf"; private final String NORMAL = "fonts/arial_bold.ttf"; private String mCustomFont = null; /** * Constructor * @param context */ public StyledButton(Context context) { super(context); } /** * Constructor * @param context * @param attrs */ public StyledButton(Context context, AttributeSet attrs) { super(context, attrs); setCustomAttributes(attrs); } /** * Set custom attributes * @param attrs */ private void setCustomAttributes(AttributeSet attrs) { TypedArray a=getContext().obtainStyledAttributes(attrs,R.styleable.StyledTextView); mCustomFont = a.getString(R.styleable.StyledTextView_fontAsset); if(mCustomFont != null) { if(!isInEditMode()) { CustomFontManager fontManager = CustomFontManager.getInstance(); super.setTypeface(fontManager.getFont(getContext().getAssets(), mCustomFont)); } } a.recycle(); } /** * Set type face */ public void setTypeface(Typeface tf, int style) { CustomFontManager fontManager = CustomFontManager.getInstance(); if(isInEditMode()) { super.setTypeface(tf,style); return; } if(mCustomFont!=null) { super.setTypeface(fontManager.getFont(getContext().getAssets(), mCustomFont)); return; } switch (style) { case Typeface.NORMAL: super.setTypeface(fontManager.getFont(getContext().getAssets(), NORMAL)); break; case Typeface.BOLD: super.setTypeface(fontManager.getFont(getContext().getAssets(), BOLD)); break; default: super.setTypeface(fontManager.getFont(getContext().getAssets(), NORMAL)); break; } } ``` } JAVA CODE CAUSING ERROR ``` private StyledButton mSignIn; public void checkIfAnyFieldIsEmpty() { if (mEmailEmpty || mPasswordEmpty) { mSignIn.setEnabled(false); } else { mSignIn.setEnabled(true); } } ``` The line of code mSignIn.setEnabled(false) is causing the error. If i comment it out or just replace it so both the if and else read mSignIn.setEnabled(true) the app runs fine. Again. The code as is works fine on the majority of devices.