From bb2ee2aa82097acc8810f83e695d3ed3178ca352 Mon Sep 17 00:00:00 2001
From: cgspine <cgspine@gmail.com>
Date: Thu, 22 Oct 2020 00:23:21 +0800
Subject: [PATCH] bugfix: npe

---
 .../qmuiteam/qmui/arch/QMUIFragmentPagerAdapter.java | 12 +++++++++++-
 .../com/qmuiteam/qmui/widget/QMUIPagerAdapter.java   |  1 -
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/arch/src/main/java/com/qmuiteam/qmui/arch/QMUIFragmentPagerAdapter.java b/arch/src/main/java/com/qmuiteam/qmui/arch/QMUIFragmentPagerAdapter.java
index 795c50f7..d4eea7a2 100644
--- a/arch/src/main/java/com/qmuiteam/qmui/arch/QMUIFragmentPagerAdapter.java
+++ b/arch/src/main/java/com/qmuiteam/qmui/arch/QMUIFragmentPagerAdapter.java
@@ -86,10 +86,14 @@ public abstract class QMUIFragmentPagerAdapter extends QMUIPagerAdapter {
     @SuppressLint("CommitTransaction")
     @Override
     protected void destroy(@NonNull ViewGroup container, int position, @NonNull Object object) {
+        Fragment fragment = (Fragment) object;
         if (mCurrentTransaction == null) {
             mCurrentTransaction = mFragmentManager.beginTransaction();
         }
-        mCurrentTransaction.detach((Fragment) object);
+        mCurrentTransaction.detach(fragment);
+        if (fragment == mCurrentPrimaryItem) {
+            mCurrentPrimaryItem = null;
+        }
     }
 
     @Override
@@ -114,9 +118,15 @@ public abstract class QMUIFragmentPagerAdapter extends QMUIPagerAdapter {
         if (fragment != mCurrentPrimaryItem) {
             if (mCurrentPrimaryItem != null) {
                 mCurrentPrimaryItem.setMenuVisibility(false);
+                if (mCurrentTransaction == null) {
+                    mCurrentTransaction = mFragmentManager.beginTransaction();
+                }
                 mCurrentTransaction.setMaxLifecycle(mCurrentPrimaryItem, Lifecycle.State.STARTED);
             }
             fragment.setMenuVisibility(true);
+            if (mCurrentTransaction == null) {
+                mCurrentTransaction = mFragmentManager.beginTransaction();
+            }
             mCurrentTransaction.setMaxLifecycle(fragment, Lifecycle.State.RESUMED);
             mCurrentPrimaryItem = fragment;
         }
diff --git a/qmui/src/main/java/com/qmuiteam/qmui/widget/QMUIPagerAdapter.java b/qmui/src/main/java/com/qmuiteam/qmui/widget/QMUIPagerAdapter.java
index 4418e3ff..85b8d355 100644
--- a/qmui/src/main/java/com/qmuiteam/qmui/widget/QMUIPagerAdapter.java
+++ b/qmui/src/main/java/com/qmuiteam/qmui/widget/QMUIPagerAdapter.java
@@ -61,7 +61,6 @@ public abstract class QMUIPagerAdapter extends PagerAdapter {
     @Override
     public final void destroyItem(@NonNull ViewGroup container, int position, @NonNull Object object) {
         destroy(container, position, object);
-
     }
 
     /**