[mobile] fix back bug

app/src/leanback/java/com/fongmi/android/tv/ui/activity/VodActivity.java

@@ -138,6 +138,10 @@ public class VodActivity extends BaseActivity implements TypePresenter.OnClickLi
         mAdapter.notifyArrayItemRangeChanged(0, mAdapter.size());
     }
 
+    private VodFragment getFragment() {
+        return (VodFragment) mPageAdapter.instantiateItem(mBinding.pager, mBinding.pager.getCurrentItem());
+    }
+
     @Override
     public void onItemClick(Class item) {
         updateFilter(item);
@@ -162,10 +166,6 @@ public class VodActivity extends BaseActivity implements TypePresenter.OnClickLi
         else super.onBackPressed();
     }
 
-    private VodFragment getFragment() {
-        return (VodFragment) mPageAdapter.instantiateItem(mBinding.pager, mBinding.pager.getCurrentItem());
-    }
-
     class PageAdapter extends FragmentStatePagerAdapter {
 
         public PageAdapter(@NonNull FragmentManager fm) {

app/src/mobile/java/com/fongmi/android/tv/ui/activity/VodActivity.java

@@ -43,6 +43,15 @@ public class VodActivity extends BaseActivity {
         Result result = Result.fromJson(getResult());
         Class type = result.getTypes().get(0);
         mBinding.text.setText(type.getTypeName());
-        getSupportFragmentManager().beginTransaction().replace(R.id.container, TypeFragment.newInstance(getKey(), type.getTypeId(), type.getTypeFlag().equals("1"))).commitAllowingStateLoss();
+        getSupportFragmentManager().beginTransaction().replace(R.id.container, TypeFragment.newInstance(getKey(), type.getTypeId(), type.getTypeFlag().equals("1")), "0").commitAllowingStateLoss();
+    }
+
+    private TypeFragment getFragment() {
+        return (TypeFragment) getSupportFragmentManager().findFragmentByTag("0");
+    }
+
+    @Override
+    public void onBackPressed() {
+        if (getFragment().canBack()) super.onBackPressed();
     }
 }