Question

我在recyclerview中显示我的设备的所有mp3文件。点击recyclerview的项目，我正在转移到其他活动，但它显示空白屏幕几秒钟然后转移到下一个活动。我的recyclerview的适配器类如下：

public class SongsAdapter extends RecyclerView.Adapter<SongsAdapter.MyViewHolder>{
    Context context;
    ArrayList<HashMap<String, String>> songList;

    public SongsAdapter(ArrayList<HashMap<String, String>> songList,Context context) {
        this.songList = songList;
        this.context=context;
    }

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

    }

    @Override
    public void onBindViewHolder(MyViewHolder holder, int position) {

        holder.textView.setText(songList.get(position).get("file_name"));
    }

    @Override
    public int getItemCount() {
        return songList.size();
    }

    public class MyViewHolder extends RecyclerView.ViewHolder  implements View.OnClickListener {
        private TextView textView;
        Context context;

        public MyViewHolder(View itemView, Context context){
            super(itemView);
            this.context = context;
            textView=(TextView)itemView.findViewById(R.id.listitemtextview);
            itemView.setOnClickListener(this);

        }

        @Override
        public void onClick(View v) {
            int position=getAdapterPosition();
            Intent intent=new Intent(context,FinalActivity.class);
            intent.putExtra("NAME",songList.get(position).get("file_name"));
            intent.putExtra("POSITION",position);
            intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
            context.startActivity(intent);
        }
    }

}

最终活动的xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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="pritish.sawant.com.musicplayer.FinalActivity">

    <ImageView
        android:id="@+id/finalactivityimageview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp" />

    <ImageButton
        android:id="@+id/shuffle"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/finalactivityimageview"
        android:layout_marginLeft="120dp"
        android:background="@android:color/white"
        android:src="@mipmap/repeat" />

    <ImageButton
        android:id="@+id/repeat"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignBaseline="@+id/shuffle"
        android:layout_below="@+id/finalactivityimageview"
        android:layout_marginLeft="50dp"
        android:layout_toRightOf="@+id/shuffle"
        android:background="@android:color/white"
        android:src="@mipmap/shuffle" />

    <LinearLayout
        android:id="@+id/linear"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/repeat"
        android:layout_marginTop="30dp"
        android:orientation="horizontal">

        <TextView
            android:id="@+id/currentTextView"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/shuffle"
            android:layout_marginLeft="30dp"
            tools:text="Hi" />

        <TextView
            android:id="@+id/finalTextView"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/repeat"
            android:layout_marginLeft="300dp"
            tools:text="Hi" />
    </LinearLayout>

    <SeekBar
        android:id="@+id/seekbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/linear"
        android:layout_marginLeft="30dp"
        android:layout_marginRight="30dp"
        android:layout_marginTop="20dp" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/seekbar"
        android:layout_marginTop="30dp"
        android:orientation="horizontal">

        <ImageButton
            android:id="@+id/previous"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:background="@android:color/white"
            android:src="@mipmap/previous"
            />

        <ImageButton
            android:id="@+id/rewind"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:background="@android:color/white"
            android:src="@mipmap/rewind" />

        <ImageButton
            android:id="@+id/play"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:background="@android:color/white"
            android:src="@mipmap/play" />

        <ImageButton
            android:id="@+id/forward"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:background="@android:color/white"
            android:src="@mipmap/forward" />

        <ImageButton
            android:id="@+id/next"
            android:layout_width="0dp"
            android:layout_weight="1"
            android:layout_height="wrap_content"
            android:background="@android:color/white"
            android:src="@mipmap/next" />

    </LinearLayout>

</RelativeLayout>

我使用AsyncTask检索所有mp3文件，但即使在我的回收站视图上显示mp3文件也需要时间

Answer 1

因为你在MyViewHolder类中启动了意图。试试这个：

public class MyViewHolder extends RecyclerView.ViewHolder {

 public TextView textView;//make public
         View mView;// make a view here


        public MyViewHolder(View itemView, Context context){
        super(itemView);
        this.context = context;
        textView=(TextView)itemView.findViewById(R.id.listitemtextview);
        mView = itemView;//--note-- make mView = iteem view


    }
      //dont set on click listner methods in here

}

现在我们的onBindViewHolder你可以在holder参数中设置列表器：

 @Override
    public void onBindViewHolder(MyViewHolder holder, int position) {


//--note replace DataItem with your Class/Model/  
final DataItem itemSong = songList.get(position);

    try {
    //this will bind to your recyclerView textView not sure why there is 
    //a string that says file_name should be itemSong.getFileName();
    holder.textView.setText(songList.get("file_name"));


     }
      } catch (Exception e) {
        e.printStackTrace();
    }



         //clicking of the recyclycleView 
holder.mView.setOnClickListener(new View.OnClickListener() {//getting viewholder class and ctor
    @Override
    public void onClick(View v) {

     Intent intent = new Intent(context,FinalActivity.class));
            //--note create a static constant string at top of class
            //    public static final String ITEM_KEY ="item_id_key";

            intent.putExtra(ITEM_KEY,itemSong);                
            context.startActivity(intent);

    }
});

知道在最后一次活动中回复意图，只需致电：

final DataItemSongs itemSong = getIntent().getExtras().getParcelable(SongsAdapter.ITEM_KEY);

从这里您可以使用itemSong对象并调用其属性并在视图中设置

nameTxt.setText(itemSong.name);

使用Intent从一个活动移动到另一个活动需要时间并显示空白屏幕

1 个答案: