我正在尝试在单击回收器视图中的CardView后启动另一个活动。新活动在单击回收器视图中的任何项目后呈现(它执行过渡并更改标题文本视图(，但它不会在布局上显示 CardView 内的任何文本视图。
OnClick 方法被设置为接口，并在第一个活动中实现。
这是我的第一个活动。我从SQLite数据库加载数据，但显示其中的代码与问题无关。
public class MainActivity extends AppCompatActivity implements RecipeAdapterMain.OnCardListener {
private TextView tv;
ArrayList<RecipeObject> recipes = new ArrayList<>();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
RecyclerView rv = findViewById(R.id.recipeListMain);
LinearLayoutManager llm = new LinearLayoutManager(this);
rv.setLayoutManager(llm);
RecipeAdapterMain adapter = new RecipeAdapterMain(recipes, this);
rv.setAdapter(adapter);
tv = findViewById(R.id.title);
}
@Override
public void onCardClick(int position) {
Intent intent = new Intent(this, RecipeActivity.class);
startActivity(intent);
}
}
这是我的适配器。
public class RecipeAdapterMain extends RecyclerView.Adapter<RecipeAdapterMain.RecipeListViewHolder> {
RecyclerView mRecyclerView;
ArrayList<RecipeObject> recipeList;
private OnCardListener mOnCardListener;
public RecipeAdapterMain(Context context, ArrayList<RecipeObject> recipeList, OnCardListener onCardListener) {
this.mOnCardListener = onCardListener;
this.recipeList = recipeList;
}
@Override
public void onAttachedToRecyclerView(RecyclerView recyclerView) {
mRecyclerView = recyclerView;
super.onAttachedToRecyclerView(recyclerView);
}
@Override
public RecipeListViewHolder onCreateViewHolder(ViewGroup parent, int i) {
View layoutView = LayoutInflater.from(parent.getContext()).inflate(R.layout.layout_recipe_main, parent, false);
RecipeListViewHolder rcv = new RecipeListViewHolder(layoutView, mOnCardListener);
return rcv;
}
@Override
public void onBindViewHolder(@NonNull RecipeListViewHolder holder, int position) {
holder.mName.setText(recipeList.get(position).getName());
}
@Override
public int getItemCount(){
return recipeList.size();
}
public class RecipeListViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
public TextView mName;
OnCardListener onCardListener;
public RecipeListViewHolder(final View view, OnCardListener onCardListener) {
super(view);
mName = view.findViewById(R.id.textViewTitle);
this.onCardListener = onCardListener;
view.setOnClickListener(this);
}
@Override
public void onClick(View v) {
onCardListener.onCardClick(getAdapterPosition());
}
}
public interface OnCardListener {
void onCardClick(int position);
}
}
我的第二个活动：
public class RecipeActivity extends AppCompatActivity {
@Override
public void onCreate(@Nullable Bundle savedInstanceState, @Nullable PersistableBundle persistentState) {
super.onCreate(savedInstanceState, persistentState);
setContentView(R.layout.layout_recipe);
}
}
这是第二个活动的布局。(layout_recipe(：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="wrap_content">
<androidx.cardview.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="@+id/textViewName"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is a test"
android:textColor="#1A1A1A"
android:textSize="18sp" />
<TextView
android:id="@+id/textViewIngr"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is a test"
android:textColor="#1A1A1A"
android:textSize="18sp" />
<TextView
android:id="@+id/textViewDire"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is a test"
android:textColor="#1A1A1A"
android:textSize="18sp" />
</LinearLayout>
</androidx.cardview.widget.CardView>
</LinearLayout>
这是第一个活动 (activity_main( 的布局：
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/AppTheme.AppBarOverlay">
</com.google.android.material.appbar.AppBarLayout>
<androidx.recyclerview.widget.RecyclerView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/recipeListMain"
android:scrollbars="vertical">
</androidx.recyclerview.widget.RecyclerView>
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="@+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:backgroundTint="@color/colorAccent"
android:layout_gravity="end|bottom"
android:layout_margin="16dp"
android:layout_marginBottom="16dp"
android:contentDescription="@string/submit"
android:src="@drawable/ic_add_black_24dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
android:onClick="openActivityCreate"/>
</androidx.coordinatorlayout.widget.CoordinatorLayout>
通过单击MainActivity上的卡片，我希望使用TextViews(这是一个测试(呈现第二个活动，但它呈现的是一个空白页。
尝试从第二个活动创建中删除@Nullable PersistableBundle persistentState