android videoview

mark一下，免得忘记

项目需要验证android　videoview对视频容器的支持，需要一个小demo　，　android程序员各种墨迹，算了，自己动手，丰衣足食．

就顺手写了个小demo，遇到一个坑，ｓｄ卡权限，不说了，6.0 搞不定，直接切换sdk到4.0，哈哈，兼容就是好，直接权限就有了，可能需要卸载，不过不是问题

源码位置：　https://github.com/godvmxi/VideoTest

Android VideoView中getDuration()方法使用问题

调用setVideoPath之后,VideoView里的MediaPlayer还未处于prepared状态,因此得不到duration.
所以只要videoView.setOnPreparedListener()方法在该监听器中去获取值就行了.

功能嘛及其简单，遍历一个目录，选择播放其中的文件．

</pre><pre code_snippet_id="1947575" snippet_file_name="blog_20161025_2_9975143" name="code" class="java">package com.example.dan.videotest;import android.media.MediaPlayer;import android.net.Uri;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.util.Log;import android.view.View;import android.view.textservice.TextInfo;import android.widget.Button;import android.widget.TextView;import android.widget.Toast;import android.widget.VideoView;import org.w3c.dom.Text;import java.io.File;public class MainActivity extends AppCompatActivity {    Button buttonList;    Button buttonNext;    Button buttonPlay;    String TAG;    int fileIndex;    TextView textViewCurFile;    TextView textViewFileList;    File[]  fileList;    VideoView videoView;    @Override    protected void onCreate(Bundle savedInstanceState) {        TAG =  new String("VideoTest");        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        buttonList = (Button)findViewById(R.id.buttonList);        buttonPlay = (Button)findViewById(R.id.buttonPlay);        buttonNext = (Button)findViewById(R.id.buttonNext);        textViewCurFile = (TextView)findViewById(R.id.textViewCurFile);        textViewFileList = (TextView)findViewById(R.id.textViewFileList);        videoView = (VideoView)findViewById(R.id.videoView);        videoView.setOnPreparedListener(new MediaPlayer.OnPreparedListener() {            @Override            public void onPrepared(MediaPlayer mp) {                Log.d(TAG, "onPrepared: " + mp.getDuration());                Toast.makeText(getApplicationContext(), "video length " +mp.getDuration(),1500).show();            }        });        fileIndex = 0;        fileList  = new File[]{};        textViewCurFile.setText("Current file -> NULL");        textViewFileList.setText("File list -> ");        buttonList.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                Log.d(TAG, "onClick: ");                //File fileDir = new File("/mnt/sdcard/Movies");                File fileDir = new File("/mnt/sdcard/Movies");                Log.d(TAG, "onClick: read ->"+ fileDir.canRead());                Log.d(TAG, "onClick: write ->"+ fileDir.canWrite());                fileList = fileDir.listFiles();                if(fileList.length > 0 ) {                    String fileListString = new String("File list -> ");                    for (int i = 0; i < fileList.length; i++) {                        Log.d(TAG, "file list -> : " + fileList[i].toString());                        fileListString = fileListString + "\n" + fileList[i].toString();                    }                    fileIndex = 0;                    textViewFileList.setText(fileListString);                    textViewCurFile.setText(fileList.length + ":" + fileIndex + "->" + fileList[fileIndex].toString());                }                else {                    fileIndex = 0;                    fileList =  new File[]{};                    Toast.makeText(getApplicationContext(), "no file in target dir",500).show();                    String fileListString = new String("File list -> NULL");                    textViewFileList.setText(fileListString);                    textViewCurFile.setText(fileList.length+":0-> NULL");                }            }        });        buttonPlay.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                //videoView.stopPlayback();                if(fileList.length > 0) {                    String curFile = fileList[fileIndex].toString();                    videoView.setVideoURI(Uri.parse(curFile));                    videoView.start();                }                else {                    Toast.makeText(getApplicationContext(), "no file in target dir",1500).show();                }            }        });        buttonNext.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                if(fileList.length <= 0 ){                    Toast.makeText(getApplicationContext(), "Click the list first",500).show();                    textViewCurFile.setText(fileList.length+":"+ (fileIndex+1)+"-> NULL");                }                else {                    fileIndex++;                    if(fileIndex >= fileList.length ){                        Toast.makeText(getApplicationContext(), "back to first file",500).show();                        fileIndex = 0;                    }                    textViewCurFile.setText(fileList.length+":"+ (fileIndex+1) +"->" + fileList[fileIndex].toString());                }            }        });    }}

布局如下：

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:id="@+id/activity_main"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context="com.example.dan.videotest.MainActivity">    <LinearLayout        android:orientation="vertical"        android:layout_width="match_parent"        android:layout_height="match_parent"        tools:layout_marginBottom="1dp"        android:layout_marginEnd="1dp"        android:layout_marginLeft="1dp"        android:layout_marginRight="1dp"        tools:layout_marginRight="1dp"        android:layout_marginStart="1dp" >        <TextView            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:text="Current File ->!"            android:id="@+id/textViewCurFile" />        <VideoView            android:layout_width="match_parent"            android:id="@+id/videoView"            android:layout_gravity="center_horizontal"            android:layout_height="400dp" />        <LinearLayout                android:orientation="horizontal"                android:layout_width="match_parent"                android:layout_height="wrap_content">                <Button                    android:layout_width="wrap_content"                    android:layout_height="wrap_content"                    android:text="List"                    android:id="@+id/buttonList" />                <Button                    android:layout_width="wrap_content"                    android:layout_height="wrap_content"                    android:text="Play"                    android:id="@+id/buttonPlay" />                <Button                    android:layout_width="wrap_content"                    android:layout_height="wrap_content"                    android:text="Next"                    android:id="@+id/buttonNext" />            </LinearLayout>        <TextView            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:text="Hello World!"            android:id="@+id/textViewFileList" />    </LinearLayout></RelativeLayout>

权限：

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.example.dan.videotest">    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"></uses-permission>    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>    <application        android:allowBackup="true"        android:icon="@mipmap/ic_launcher"        android:label="@string/app_name"        android:supportsRtl="true"        android:theme="@style/AppTheme">        <activity android:name=".MainActivity">            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application></manifest>