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listview.xml如下 [html] view plaincopy <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="fill_parent" > <ImageView android:layout_width="wrap_content" android:layout_height="wrap_content" android:id="@+id/iv" /> <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:id="@+id/tv" /> </LinearLayout> 1、我先按照参考的第一个url来写的 [java] view plaincopy package com.lp; import java.util.ArrayList; import android.app.ListActivity; import android.content.Context; import android.database.Cursor; import android.net.Uri; import android.os.Bundle; import android.provider.MediaStore; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ImageView; import android.widget.TextView; /** * 本实例,我们将通过检索SDCard上的Video信息 * 在MediaStore中,MediaStore.Video.Media中就有Video相关信息, * 同时MediaStore.Video.Thumbnails中含有各个video对应的缩略图信息 * * @author Administrator * */ public class MainActivity extends ListActivity { private Cursor cursor; private ArrayList<VideoInfo> videoList = new ArrayList<MainActivity.VideoInfo>(); private ImageView img; public void onCreate(Bundle savedInstanceState){ super.onCreate(savedInstanceState); init(); } private void init(){ String[] thumbColumns = new String[]{ MediaStore.Video.Thumbnails.DATA, MediaStore.Video.Thumbnails.VIDEO_ID }; String[] mediaColumns = new String[]{ MediaStore.Video.Media.DATA, MediaStore.Video.Media._ID, MediaStore.Video.Media.TITLE, MediaStore.Video.Media.MIME_TYPE }; //首先检索SDcard上所有的video cursor = this.managedQuery(MediaStore.Video.Media.EXTERNAL_CONTENT_URI, mediaColumns, null, null, null); while(cursor.moveToNext()){ VideoInfo info = new VideoInfo(); info.filePath = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Video.Media.DATA)); info.mimeType = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Video.Media.MIME_TYPE)); info.title = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Video.Media.TITLE)); //获取当前Video对应的Id,然后根据该ID获取其Thumb int id = cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Video.Media._ID)); String selection = MediaStore.Video.Thumbnails.VIDEO_ID +"=?"; String[] selectionArgs = new String[]{ id+"" }; Cursor thumbCursor = this.managedQuery(MediaStore.Video.Thumbnails.EXTERNAL_CONTENT_URI, thumbColumns, selection, selectionArgs, null); if(thumbCursor.moveToFirst()){ info.thumbPath = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Video.Thumbnails.DATA)); } //然后将其加入到videoList videoList.add(info); } System.out.println(videoList.size()); //然后需要设置ListView的Adapter了,使用我们自定义的Adatper VideoAdapter adapter = new VideoAdapter(this); this.getListView().setAdapter(adapter); } class VideoInfo{ String filePath; String mimeType; String thumbPath; String title; } class ViewHolder{ ImageView thumbImage; TextView titleText; } /** * 定义一个Adapter来显示缩略图和视频title信息 * @author Administrator * */ private class VideoAdapter extends BaseAdapter{ private Context mContext; private LayoutInflater inflater; public VideoAdapter(Context context){ this.mContext = context; this.inflater = LayoutInflater.from(context); this.inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE); } @Override public int getCount() { // TODO Auto-generated method stub return videoList.size(); } @Override public Object getItem(int p) { // TODO Auto-generated method stub return videoList.get(p); } @Override public long getItemId(int p) { // TODO Auto-generated method stub return p; } @Override public View getView(int position, View convertView, ViewGroup parent) { ViewHolder holder ; if(convertView == null){ holder = new ViewHolder(); convertView = inflater.inflate(R.layout.listview, null); holder.thumbImage = (ImageView)convertView.findViewById(R.id.iv); holder.titleText = (TextView)convertView.findViewById(R.id.tv); convertView.setTag(holder); }else{ holder = (ViewHolder)convertView.getTag(); } //显示信息 holder.titleText.setText(videoList.get(position).title); if(videoList.get(position).thumbPath != null){ holder.thumbImage.setImageURI(Uri.parse(videoList.get(position).thumbPath)); } return convertView; } } } 但是 结果是能得到title 得不到缩略图 貌似大家都说好使 但是我这里就是不行 很是纳闷 后来 我就直接看了下com.android.providers.media下面的external-ef8261f.db 数据库的结构如下图: video 这里面罗列的sdcard的所有视频文件 我们可以得到 名字 类型 持续时间 大小等有用的数据 再看一下 videothumbnails 这里面是没有数据的!!! 这个就是原因了 所以我们根据VIDEO_ID在videothumbnails表里面肯定是什么也得不到的 2、 仔细查看MediaStore.Video.Thumbnails类里面的方法 可以发现 提供了一个getThumbnail()方法 可以直接得到缩略图 [java] view plaincopy package com.lp; import java.util.ArrayList; import android.app.ListActivity; import android.content.Context; import android.database.Cursor; import android.net.Uri; import android.os.Bundle; import android.provider.MediaStore; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ImageView; import android.widget.TextView; /** * 本实例,我们将通过检索SDCard上的Video信息 * 在MediaStore中,MediaStore.Video.Media中就有Video相关信息, * 同时MediaStore.Video.Thumbnails中含有各个video对应的缩略图信息 * * @author Administrator * */ public class MainActivity extends ListActivity { private Cursor cursor; private ArrayList<VideoInfo> videoList = new ArrayList<MainActivity.VideoInfo>(); private ImageView img; public void onCreate(Bundle savedInstanceState){ super.onCreate(savedInstanceState); init(); } private void init(){ String[] thumbColumns = new String[]{ MediaStore.Video.Thumbnails.DATA, MediaStore.Video.Thumbnails.VIDEO_ID }; String[] mediaColumns = new String[]{ MediaStore.Video.Media.DATA, MediaStore.Video.Media._ID, MediaStore.Video.Media.TITLE, MediaStore.Video.Media.MIME_TYPE }; //首先检索SDcard上所有的video cursor = this.managedQuery(MediaStore.Video.Media.EXTERNAL_CONTENT_URI, mediaColumns, null, null, null); while(cursor.moveToNext()){ VideoInfo info = new VideoInfo(); info.filePath = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Video.Media.DATA)); info.mimeType = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Video.Media.MIME_TYPE)); info.title = cursor.getString(cursor.getColumnIndexOrThrow(MediaStore.Video.Media.TITLE)); //获取当前Video对应的Id,然后根据该ID获取其Thumb int id = cursor.getInt(cursor.getColumnIndexOrThrow(MediaStore.Video.Media._ID)); BitmapFactory.Options options = new BitmapFactory.Options(); options.inDither = false; options.inPreferredConfig = Bitmap.Config.ARGB_8888; info.b = MediaStore.Video.Thumbnails.getThumbnail(getContentResolver(), id, Images.Thumbnails.MICRO_KIND, options); //然后将其加入到videoList videoList.add(info); } System.out.println(videoList.size()); //然后需要设置ListView的Adapter了,使用我们自定义的Adatper VideoAdapter adapter = new VideoAdapter(this); this.getListView().setAdapter(adapter); } class VideoInfo{ String filePath; String mimeType; Bitmap b; String title; } class ViewHolder{ ImageView thumbImage; TextView titleText; } /** * 定义一个Adapter来显示缩略图和视频title信息 * @author Administrator * */ private class VideoAdapter extends BaseAdapter{ private Context mContext; private LayoutInflater inflater; public VideoAdapter(Context context){ this.mContext = context; this.inflater = LayoutInflater.from(context); this.inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE); } @Override public int getCount() { // TODO Auto-generated method stub return videoList.size(); } @Override public Object getItem(int p) { // TODO Auto-generated method stub return videoList.get(p); } @Override public long getItemId(int p) { // TODO Auto-generated method stub return p; } @Override public View getView(int position, View convertView, ViewGroup parent) { ViewHolder holder ; if(convertView == null){ holder = new ViewHolder(); convertView = inflater.inflate(R.layout.listview, null); holder.thumbImage = (ImageView)convertView.findViewById(R.id.iv); holder.titleText = (TextView)convertView.findViewById(R.id.tv); convertView.setTag(holder); }else{ holder = (ViewHolder)convertView.getTag(); } //显示信息 holder.titleText.setText(videoList.get(position).title); if(videoList.get(position).b != null){ holder.thumbImage.setImageBitmap(videoList.get(position).b); } return convertView; } } } 从video表里面得到关于视频的一些数据,如:时间、大小、类型等 2、我们可以通过 Java代码 MediaStore.Video.Thumbnails.getThumbnail(getContentResolver(), id, Images.Thumbnails.MICRO_KIND, options); 直接得到缩略图 代码见附件 转载:http://lipeng88213.iteye.com/blog/1182265