Android：更改设备字体后出现NullPointerException？

Question

例如，我有两个活动HomeScreen和PostListScreen。

步骤 1.从HomeScreen导航到PostListScreen。 2.最小化应用 3.进入系统设置，然后增加/减少字体。 4.再次打开应用程序

现在，我遇到了以下错误。

java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.LinearLayout.setVisibility(int)' on a null object reference
        at *package**activity*.isVisible(*activity*.java:505)
        at *package**activity*.searchData(*activity*.java:487)
        at *package**activity*$3.onTextChanged(*activity*.java:191)
        at android.widget.TextView.sendOnTextChanged(TextView.java:9786)
        at android.widget.TextView.setText(TextView.java:5765)
        at android.widget.TextView.setText(TextView.java:5603)
        at android.widget.EditText.setText(EditText.java:122)
        at android.widget.TextView.setText(TextView.java:5560)
        at android.widget.TextView.onRestoreInstanceState(TextView.java:5428)
        at android.view.View.dispatchRestoreInstanceState(View.java:18751)
        at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3831)
        at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3831)
        at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3831)
        at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3831)
        at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3831)
        at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3831)
        at android.view.ViewGroup.dispatchRestoreInstanceState(ViewGroup.java:3831)
        at android.view.View.restoreHierarchyState(View.java:18729)
        at com.android.internal.policy.PhoneWindow.restoreHierarchyState(PhoneWindow.java:2171)
        at android.app.Activity.onRestoreInstanceState(Activity.java:1135)
        at android.app.Activity.performRestoreInstanceState(Activity.java:1090)
        at android.app.Instrumentation.callActivityOnRestoreInstanceState(Instrumentation.java:1338)
        at android.app.ActivityThread.handleStartActivity(ActivityThread.java:3077)
        at android.app.servertransaction.TransactionExecutor.performLifecycleSequence(TransactionExecutor.java:180)
        at android.app.servertransaction.TransactionExecutor.cycleToPath(TransactionExecutor.java:165)
        at android.app.servertransaction.TransactionExecutor.executeLifecycleState(TransactionExecutor.java:142)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:70)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1906)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:193)
        at android.app.ActivityThread.main(ActivityThread.java:6863)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:537)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

因此，基本上所有引用[LinearLayout,RecyclerView e.t.c]的值都为 null 。

为此，我已经在google / StackOverflow / git等上花费了数小时，但无法为此找到解决方案。

应用配置

    compileSdkVersion 27
    minSdkVersion 19
    targetSdkVersion 27
    multiDexEnabled true