我想在数据绑定结构中设置动态布局高度.
我试了一下,但我得到了这个例外:
@H_502_8@java.lang.NullPointerException: Attempt to invoke virtual method 'int java.lang.Integer.intValue()' on a null object reference at databinding.ItemGroupCommentsBinding.executeBindings(ItemGroupCommentsBinding.java:147) at android.databinding.ViewDataBinding.executePendingBindings(ViewDataBinding.java:355) at view.base.adapter.DataBindingAdapter.onBindViewHolder(DataBindingAdapter.java:32) at view.base.adapter.DataBindingAdapter.onBindViewHolder(DataBindingAdapter.java:15) at android.support.v7.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:6279) at android.support.v7.widget.RecyclerView$Adapter.bindViewHolder(RecyclerView.java:6312) at android.support.v7.widget.RecyclerView$Recycler.tryBindViewHolderByDeadline(RecyclerView.java:5258) at android.support.v7.widget.RecyclerView$Recycler.tryGetViewHolderForPositionByDeadline(RecyclerView.java:5521) at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5363) at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:5359) at android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2141) at android.support.v7.widget.GridLayoutManager.layoutChunk(GridLayoutManager.java:556) at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1488) at android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:585) at android.support.v7.widget.GridLayoutManager.onLayoutChildren(GridLayoutManager.java:170) at android.support.v7.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:3506) at android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.java:3254) at android.support.v7.widget.RecyclerView.onLayout(RecyclerView.java:3767) at android.view.View.layout(View.java:15604) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.support.v4.widget.SwipeRefreshLayout.onLayout(SwipeRefreshLayout.java:636) at android.view.View.layout(View.java:15604) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1076) at android.view.View.layout(View.java:15604) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15604) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15604) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703) at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1557) at android.widget.LinearLayout.onLayout(LinearLayout.java:1466) at android.view.View.layout(View.java:15604) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15604) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508) at android.view.View.layout(View.java:15604) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703) at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1557) at android.widget.LinearLayout.onLayout(LinearLayout.java:1466) at android.view.View.layout(View.java:15604) at android.view.ViewGroup.layout(ViewGroup.java:4966) at android.widget.FrameLayout.layoutChildren(FrameLayout.java:573) at android.widget.FrameLayout.onLayout(FrameLayout.java:508)
代码是:
Fragment.java:
@H_502_8@@Override public View onCreateView(LayoutInflater inflater,ViewGroup container,Bundle savedInstanceState) { db = DataBindingUtil.inflate(inflater,R.layout.fragment_group_comments,container,false); getSubComponent().inject(this); db.setVariable(BR.height,0); // Inflate the layout for this fragment return db.getRoot(); } @BindingAdapter("android:layout_height") public static void setLayoutHeight(View view,float commentNumber) { Timber.e("setLayoutHeight " + commentNumber); try { GridLayoutManager.LayoutParams layoutParams = (GridLayoutManager.LayoutParams) view.getLayoutParams(); if (10 <= commentNumber && commentNumber < 10) { layoutParams.height = 400; } else if (11 <= commentNumber && commentNumber < 20) { layoutParams.height = 500; } view.setLayoutParams(layoutParams); } catch (Exception ignore) {} }
item_.xml
@H_502_8@
最佳答案
您需要将commentNumber类型从float更改为Integer或更改为绑定适配器中的int:
@H_502_8@@BindingAdapter("android:layout_height") public static void setLayoutHeight(View view,Integer commentNumber) { // your code staff }
检查the example,其中@BindingAdapter用于设置视图的填充.