替换黑夜模式的背景，bugly bugfix

modules/mogo-module-apps/src/main/java/com/mogo/module/apps/model/AppsModel.java

@@ -25,7 +25,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
  * 加载并保存 app 列表
  */
 public class AppsModel {
-    
+
     private static final String TAG = "AppsModel";
 
     private static volatile AppsModel sInstance;
@@ -57,7 +57,6 @@ public class AppsModel {
         if ( mPagedApps != null ) {
             mPagedApps.clear();
         }
-        mPagedApps = null;
         mContext = null;
         mAppFilter = null;
         sInstance = null;
@@ -116,9 +115,12 @@ public class AppsModel {
         if ( TextUtils.isEmpty( packageName ) ) {
             return;
         }
-        if ( mPagedApps.isEmpty() ) {
+        if ( mPagedApps == null || mPagedApps.isEmpty() ) {
             return;
         }
+        if ( mAppFilter == null ) {
+            mAppFilter = new AppFilterImpl( mContext );
+        }
         try {
             final PackageManager packageManager = mContext.getPackageManager();
             PackageInfo packageInfo = packageManager.getPackageInfo( packageName, 0 );
@@ -183,6 +185,9 @@ public class AppsModel {
         if ( TextUtils.isEmpty( packageName ) ) {
             return;
         }
+        if ( mPagedApps == null || mPagedApps.isEmpty() ) {
+            return;
+        }
         try {
             int pageIndex = getPageIndex( packageName, false );
             if ( pageIndex == -1 ) {