如何从 getView 设置正确 SeekBar 的进度？

Question

我有一个带有自定义列表项的 ListView，每个列表项中有一个按钮和一个 SeekBar。现在，当单击按钮时，音频开始播放，我想为单击按钮的位置设置 SeekBar 的进度。使用我拥有的代码，正确的 SeekBar 开始移动，但是当我上下滚动几次时，另一个 SeekBar 开始移动。我已经尝试了很多东西，这是我的最后一个：

import android.app.Activity;
import android.content.Context;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.net.Uri;
import android.os.Handler;
import android.support.annotation.LayoutRes;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageButton;
import android.widget.SeekBar;
import android.widget.TextView;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;

public class MyListAdapter extends ArrayAdapter<Audio> {

ArrayList<Audio> audios;
Context context;
int resource;

private static MediaPlayer mediaPlayer;

public Handler mHandler = new Handler();
TextView totalTime;
TextView playingTime;

private MyListAdapter(@NonNull Context context, @LayoutRes int resource, @NonNull ArrayList<Audio> audios) {
    super(context, resource, audios);
    Collections.reverse(audios);
    this.audios = audios;
    this. context = context;
    this.resource = resource;
}

@NonNull
 @Override
 public View getView(final int position, @Nullable View convertView, @NonNull ViewGroup parent) {
    final ViewHolder viewHolder;
    View row;
    if (convertView == null) {
        LayoutInflater layoutInflater = (LayoutInflater) getContext().getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
        row = layoutInflater.inflate(R.layout.audio_cell, parent, false);

        viewHolder = new ViewHolder();
        viewHolder.playButton = (ImageButton) row.findViewById(R.id.playButton);
        viewHolder.seekBar = (SeekBar) row.findViewById(R.id.seekBar);
        viewHolder.playButton.setTag(position);
        viewHolder.seekBar.setTag(position);
        row.setTag(viewHolder);
    } else {
        row = convertView;
        viewHolder = (ViewHolder) row.getTag();
    }

    viewHolder.seekBar.setProgress(0);
    //I get the audio url here
    final Audio audio = getItem(position);
    assert audio != null;
    String theURL = audio.getURL();

    //Button Click
    viewHolder.playButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            //here I call the method to play the audio and after that I want 
            //to update the SeekBar
            playAudio(theURL);

            updateSeekBar(viewHolder.seekBar);
        }
    });
    return row;
}

private void updateSeekBar(final SeekBar sb) {

    Runnable mUpdateTimeTask = new Runnable() {
        @Override
        public void run() {
            if (mediaPlayer != null && mediaPlayer.isPlaying()) {
                int mCurrentPosition = mediaPlayer.getCurrentPosition() / 1000;
                mHandler.postDelayed(this, 100);
                sb.setProgress(mCurrentPosition);
            }
        }
    };
    mHandler.postDelayed(mUpdateTimeTask, 100);
}
}

这是我的 ViewHolder 类：

public class ViewHolder {
    public ImageButton playButton;
    public SeekBar seekBar;
}

现在正如我所说，我尝试了很多东西，但似乎没有任何效果，我想我尝试过的东西都是一样的，因为我每次都得到相同的结果。只要我上下滚动几次，它就会在不同的 SeekBar 上设置进度。任何帮助表示赞赏！

Answer 1

列表视图循环使用 getView() 中的视图，因为您正在使用 getTag() 和 setTAg()。因此，当单击项目时，它会反映在其他一些位置，并且歌曲开始在其他位置播放，因为它正在重用查看。

解决这个问题。创建一个全局 int 值来存储被点击项目的位置。

private int mSelectedItem = -1;

每当点击播放按钮时，将该位置添加到 mSelectedItem

viewHolder.playButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
        //Store the position here
         mSelectedItem=position;
            //here I call the method to play the audio and after that I want 
            //to update the SeekBar
            playAudio(theURL);

            updateSeekBar(viewHolder.seekBar);
        }
    });

然后像这样更新 seekBar

调用方法时传递位置

updateSeekBar(viewHolder.seekBar,position);

检查位置是否与您单击的位置相同并更新搜索栏

private void updateSeekBar(final SeekBar sb,int position) {
    final Runnable mUpdateTimeTask=null;
    if(mSelectedItem==position){
         mUpdateTimeTask = new Runnable() {
           @Override
           public void run() {
               if (mediaPlayer != null && mediaPlayer.isPlaying()) {
                    int mCurrentPosition = mediaPlayer.getCurrentPosition() / 1000;
                    mHandler.postDelayed(this, 100);
                    sb.setProgress(mCurrentPosition);
                }
            }
        };
        mHandler.postDelayed(mUpdateTimeTask, 100);
    }else{
         mHandler.removeCallbacks(mUpdateTimeTask);
         sb.setProgress(0);
    }
}    

Answer 2

你可以像下面这样写..

1. 声明变量

       private MediaPlayer mediaPlayer;
       private double startTime = 0;
       private double finalTime = 0;
       public  int oneTimeOnly = 0;
   

2. 更改 viewHolder.playButton

     viewHolder.playButton.setOnClickListener(new View.OnClickListener() {
               @Override
               public void onClick(View view) {
                   //Being...
   
                   try {
                       mediaPlayer = new MediaPlayer();
                       mediaPlayer.setDataSource(theURL);
                       try {
   
   
                           // Log.e("ddd***",tv_directory.getText().toString());
   
                           if(mediaPlayer.isPlaying()){
                               Log.e("isplaying**",mediaPlayer.isPlaying()+"");
   
                               mediaPlayer.pause();
                               finalTime = mediaPlayer.getDuration();
                               startTime = mediaPlayer.getCurrentPosition();
   
                               if (oneTimeOnly == 0) {
                                   seekBar.setMax((int) finalTime);
                                   oneTimeOnly = 1;
                               }
   
   
                           }else{
                               // Log.e("isplaying**",mediaPlayer.isPlaying()+"");
   
   
   
                               mediaPlayer.prepare();
                               //mediaPlayer.start();
   
   
                               mediaPlayer.start();
   
   
                               finalTime = mediaPlayer.getDuration();
                               startTime = mediaPlayer.getCurrentPosition();
   
                               if (oneTimeOnly == 0) {
                                   seekBar.setMax((int) finalTime);
                                   oneTimeOnly = 1;
                               }
   
   
   
   
   
                           }
                       } catch (Exception e) {
                           Log.e("err***",e.toString());
                       }
   
   
   
                       myHandler.postDelayed(new Runnable(){
                           public void run() {
                               startTime = mediaPlayer.getCurrentPosition();
                               tv_start_time.setText(String.format("%d min, %d sec",
                                       TimeUnit.MILLISECONDS.toMinutes((long) startTime),
                                       TimeUnit.MILLISECONDS.toSeconds((long) startTime) -
                                               TimeUnit.MINUTES.toSeconds(TimeUnit.MILLISECONDS.
                                                       toMinutes((long) startTime)))
   
                               );
   
   
   
                               seekBar.setProgress((int) startTime);
   
                               myHandler.postDelayed(this, 100);
                           }
                       }, 100);
   
   
                   } catch (Exception e) {
                       Log.e("err***",e.toString());
   
                   }
                   //End....
               }
           });
   

Answer 3

好的，我找到了问题，因为

if(convertView == null)

仅适用于屏幕上出现的第一个项目。 Here 它解释了为什么会发生这种情况。在我的情况下，this 答案有效。这不是最好的方法，但对于具有少量项目的 ListView 来说，它可以工作。