如何在适配器中使用 getFragmentManager()

Posted 2023-04-15

【中文标题】如何在适配器中使用 getFragmentManager()

【英文标题】：How use getFragmentManager() in adapter

【发布时间】：2018-05-09 22:56:55

【问题描述】：

。如何在适配器中使用此代码？ （我在 SecondFragment 中使用此代码）。

Fragment frg = null;
frg = getFragmentManager().findFragmentByTag("OneFragment");
final FragmentTransaction ft = getFragmentManager().beginTransaction();
ft.detach(frg);
ft.attach(frg);
ft.commit();

而且适配器中的这种方式不起作用：

Fragment frg = null;
frg = ((Activity) context).getFragmentManager().findFragmentByTag("OneFragment");
final FragmentTransaction ft = ((Activity) context).getFragmentManager().beginTransaction();
ft.detach(frg);
ft.attach(frg);
ft.commit();

并向我显示错误：

Required:
android.support.v4.app.Fragment
Found:
android.app.FragmentManage

在我的适配器中（我需要在我的适配器中使用getFragmentManager()。）：

import android.content.Context;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.TextView;

import me.bazaarche.Fragment.FilterFragment;
import me.bazaarche.Fragment.HomeFragment;
import me.bazaarche.app.R;

public class CategorySub1Adapter extends RecyclerView.Adapter<CategorySub1Adapter.ViewHolder> 

    private Context context;
    private String[] categorySub1Name;
    int categoryPosition;
    int categorySub0Position;
    FragmentManager fragmentManager;

    public CategorySub1Adapter(Context context, FragmentManager fragmentManager, String[] categorySub1Name, int categoryPosition, int categorySub0Position) 
        this.context = context;
        this.categorySub1Name = categorySub1Name;
        this.categoryPosition = categoryPosition;
        this.categorySub0Position = categorySub0Position;
        this.fragmentManager = fragmentManager;
    

    class ViewHolder extends RecyclerView.ViewHolder 
        View categorySub1Menu;
        TextView categorySub1Name;

        ViewHolder(View itemView) 
            super(itemView);
            categorySub1Menu = itemView.findViewById(R.id.category_sub0_menu);
            categorySub1Name = itemView.findViewById(R.id.category_sub1_name);
        
    

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) 
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_category_sub1, parent, false);
        return new ViewHolder(view);
    

    @Override
    public void onBindViewHolder(final ViewHolder holder, final int position) 
        holder.categorySub1Name.setText(categorySub1Name[position]);
        Animation animation = AnimationUtils.loadAnimation(context, R.anim.open_menu);
        animation.setStartOffset(30 * position);
        holder.itemView.startAnimation(animation);

        HomeFragment.adAdapter.ClearList();
        HomeFragment.last_ad_id = 0;
        FilterFragment.categoryPosition = categoryPosition;
        FilterFragment.categorySub0Position = categorySub0Position;
        FilterFragment.categorySub1Position = position;
        HomeFragment.adAdapter.LoadMore();

        Fragment frg = null;
        frg = fragmentManager.getFragmentManager().findFragmentByTag("OneFragment");
        final FragmentTransaction ft = fragmentManager.getFragmentManager().beginTransaction();
        ft.detach(frg);
        ft.attach(frg);
        ft.commit();
    

    @Override
    public int getItemCount() 
        return categorySub1Name.length;
    

我需要在我的适配器中使用getFragmentManager()。

【参考方案1】：

将您的导入更改为：

import android.support.v4.app.FragmentManager;
import android.support.v4.app.Fragment;

尝试使用此更改Framgnet：

Fragment frg = null;
frg = ((Activity) context).getSupportFragmentManager().findFragmentByTag("OneFragment");
final FragmentTransaction ft = ((Activity) context).getSupportFragmentManager().beginTransaction();
ft.detach(frg);
ft.attach(frg);
ft.commit();

【讨论】：

适配器 getActivity() 不可用

在适配器中：this.context. 之后，getSupportFragmentManager() 不可用。

向我展示你的导入，并检查你是否有我提供给你的导入，谢谢。

getFragmentManager() 不适用于this.context.

我打错了...改成((Activity) context)

【参考方案2】：

CategorySub1Adapter 构造函数的变化。

public CategorySub1Adapter(Context context, FragmentManager fragmentManager, String[] categorySub1Name, int categoryPosition, int categorySub0Position) 
    this.context = context;
    this.categorySub1Name = categorySub1Name;
    this.categoryPosition = categoryPosition;
    this.categorySub0Position = categorySub0Position;
    this.fragmentManager = fragmentManager;

到

     private Context context;
     private Activity mActivity;

    public CategorySub1Adapter(Activity mActivity, FragmentManager fragmentManager, String[] categorySub1Name, int categoryPosition, int categorySub0Position) 
    this.mActivity = mActivity;
    this.categorySub1Name = categorySub1Name;
    this.categoryPosition = categoryPosition;
    this.categorySub0Position = categorySub0Position;
    this.fragmentManager = fragmentManager;

尝试改变

mYourAdapter = new CategorySub1Adapter(getActivity(),........);

并改变它

    Fragment frg = null;
    frg = mActivity.getSupportFragmentManager().findFragmentByTag("OneFragment");
    final FragmentTransaction ft = mActivity.getSupportFragmentManager().beginTransaction();
    ft.detach(frg);
    ft.attach(frg);
    ft.commit();

如果你想要上下文

 @Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) 
    View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_category_sub1, parent, false);

    // get context
    context=parent.getContext();

    return new ViewHolder(view);

【参考方案3】：

在onBindViewHolder() 方法内 你可以使用这个 kotlin 代码的 java 等价物

val fm=(holder.itemView.context as FragmentActivity).supportFragmentManager

【讨论】：

请阅读How to answer并更新您的答案。