22_Android中的本地音乐播放器和网络音乐播放器的编写,本地视频播放器和网络视频播放器,照相机案例,偷拍案例实现

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22_Android中的本地音乐播放器和网络音乐播放器的编写,本地视频播放器和网络视频播放器,照相机案例,偷拍案例实现

涂作权 2015-07-25 02:00:00 浏览1389
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1 编写以下案例:

当点击了播放之后,在手机上的/mnt/sdcard2/natural.mp3就会播放。

2 编写布局文件activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical"

    tools:context=".MainActivity" >

 

    <EditText

        android:id="@+id/et_path"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:hint="请输入要播放文件的路径" />

 

    <LinearLayout

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:orientation="horizontal" >

 

        <Button

            android:id="@+id/bt_play"

            android:onClick="play"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:text="播放" />

        <Button

              android:id="@+id/bt_pause"

            android:onClick="pause"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:text="暂停" />

        <Button

              android:id="@+id/bt_stop"

            android:onClick="stop"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:text="停止" />

        <Button

              android:id="@+id/bt_replay"

            android:onClick="replay"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:text="重播" />

    </LinearLayout>

 

</LinearLayout>

3 编写MainActivity

package com.itheima.musicplayer;

 

import java.io.File;

import java.io.IOException;

 

import android.app.Activity;

import android.media.AudioManager;

import android.media.MediaPlayer;

import android.media.MediaPlayer.OnCompletionListener;

import android.os.Bundle;

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.Toast;

 

public class MainActivity extends Activity {

    private EditText et_path;

   

    private MediaPlayer mediaPlayer;

   

    private Button bt_play,bt_pause,bt_stop,bt_replay;

 

    @Override

    protected void onCreate(Bundle savedInstanceState) {

       super.onCreate(savedInstanceState);

       setContentView(R.layout.activity_main);

       et_path = (EditText) findViewById(R.id.et_path);

       bt_play = (Button) findViewById(R.id.bt_play);

       bt_pause = (Button) findViewById(R.id.bt_pause);

       bt_stop = (Button) findViewById(R.id.bt_stop);

       bt_replay = (Button) findViewById(R.id.bt_replay);

    }

    /**

     * 播放

     * @param view

     */

    public void play(View view) {

       String filepath = et_path.getText().toString().trim();

       File file = new File(filepath);

       if(file.exists()){

           try {

              mediaPlayer = new MediaPlayer();

              mediaPlayer.setDataSource(filepath);//设置播放的数据源。

               mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);

              mediaPlayer.prepare();//准备开始播放 播放的逻辑是c代码在新的线程里面执行。

              mediaPlayer.start();

              bt_play.setEnabled(false);

              mediaPlayer.setOnCompletionListener(new OnCompletionListener() {

                  @Override

                  public void onCompletion(MediaPlayer mp) {

                     bt_play.setEnabled(true);

                  }

              });

           } catch (Exception e) {

              e.printStackTrace();

              Toast.makeText(this, "播放失败", 0).show();

           }

       }else{

           Toast.makeText(this, "文件不存在,请检查文件的路径", 0).show();

       }

    }

    /**

     * 暂停

     * @param view

     */

    public void pause(View view) {

       if("继续".equals(bt_pause.getText().toString())){

           mediaPlayer.start();

           bt_pause.setText("暂停");

           return;

       }

       if(mediaPlayer!=null&&mediaPlayer.isPlaying()){

           //这里表示的是暂停功能

           mediaPlayer.pause();

           bt_pause.setText("继续");

       }

    }

   

    /**

     * 停止

     * @param view

     */

    public void stop(View view) {

       if(mediaPlayer!=null&&mediaPlayer.isPlaying()){

           //通过stop方法停止播放音乐

           mediaPlayer.stop();

           mediaPlayer.release();

           mediaPlayer = null;

       }

       bt_pause.setText("暂停");

       bt_play.setEnabled(true);

    }

    /**

     * 重播

     * @param view

     */

    public void replay(View view) {

       if(mediaPlayer!=null&&mediaPlayer.isPlaying()){

           //通过seekTo方法指定到某个位置播放音乐

           mediaPlayer.seekTo(0);

       }else{

           play(view);

       }

       bt_pause.setText("暂停");

    }

}

如果想播放网络上的音乐,需要把上面的play代码改成:

/**

     * 播放

     *

     * @param view

     */

    public void play(View view) {

       String filepath = et_path.getText().toString().trim();

       // http://

       if (filepath.startsWith("http://")) {

           try {

              mediaPlayer = new MediaPlayer();

              mediaPlayer.setDataSource(filepath);// 设置播放的数据源。

               mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);

              // mediaPlayer.prepare();//同步的准备方法。

              mediaPlayer.prepareAsync();// 异步的准备

              mediaPlayer.setOnPreparedListener(new OnPreparedListener() {

                  @Override

                  public void onPrepared(MediaPlayer mp) {

                     mediaPlayer.start();

                     bt_play.setEnabled(false);

                  }

              });

              mediaPlayer.setOnCompletionListener(new OnCompletionListener() {

                  @Override

                  public void onCompletion(MediaPlayer mp) {

                     bt_play.setEnabled(true);

                  }

              });

           } catch (Exception e) {

              e.printStackTrace();

              Toast.makeText(this, "播放失败", 0).show();

           }

        } else {

           Toast.makeText(this, "请检查文件的路径", 0).show();

       }

    }

==============================================================================

  1. 视频播放器,实现播放暂停停止重播。案例截图如下:

  1. 播放布局文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical"

    tools:context=".MainActivity" >

 

    <EditText

        android:id="@+id/et_path"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:hint="请输入要播放文件的路径" />

 

    <SeekBar

        android:id="@+id/seekBar1"

        android:layout_width="match_parent"

        android:layout_height="wrap_content" />

 

    <LinearLayout

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:orientation="horizontal" >

 

        <Button

            android:id="@+id/bt_play"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:onClick="play"

            android:text="播放" />

 

        <Button

            android:id="@+id/bt_pause"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:onClick="pause"

            android:text="暂停" />

 

        <Button

            android:id="@+id/bt_stop"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:onClick="stop"

            android:text="停止" />

 

        <Button

            android:id="@+id/bt_replay"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:onClick="replay"

            android:text="重播" />

    </LinearLayout>

 

    <SurfaceView

        android:id="@+id/sv"

        android:layout_width="fill_parent"

        android:layout_height="fill_parent" />

 

</LinearLayout>

  1. 编写MainActivity,代码如下:

package com.itheima.musicplayer;

 

import java.io.File;

import java.io.IOException;

import java.util.Timer;

import java.util.TimerTask;

 

import android.app.Activity;

import android.media.AudioManager;

import android.media.MediaPlayer;

import android.media.MediaPlayer.OnCompletionListener;

import android.os.Bundle;

import android.view.SurfaceHolder;

import android.view.SurfaceHolder.Callback;

import android.view.SurfaceView;

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.SeekBar;

import android.widget.SeekBar.OnSeekBarChangeListener;

import android.widget.Toast;

 

public class MainActivity extends Activity {

    private EditText et_path;

    private MediaPlayer mediaPlayer;

   

    private Button bt_play,bt_pause,bt_stop,bt_replay;

   

    private SurfaceView sv;

    private SurfaceHolder holder;

   

    private int position;

    private String filepath;

 

    private SeekBar seekBar1;

   

    private Timer timer;

    private TimerTask task;

   

    @Override

    protected void onCreate(Bundle savedInstanceState) {

       super.onCreate(savedInstanceState);

       setContentView(R.layout.activity_main);

       et_path = (EditText) findViewById(R.id.et_path);

       bt_play = (Button) findViewById(R.id.bt_play);

       bt_pause = (Button) findViewById(R.id.bt_pause);

       bt_stop = (Button) findViewById(R.id.bt_stop);

       bt_replay = (Button) findViewById(R.id.bt_replay);

      

       seekBar1 = (SeekBar) findViewById(R.id.seekBar1);

       seekBar1.setOnSeekBarChangeListener(new OnSeekBarChangeListener() {

          

           @Override

           public void onStopTrackingTouch(SeekBar seekBar) {

              int postion = seekBar.getProgress();

              mediaPlayer.seekTo(postion);

           }

          

           @Override

           public void onStartTrackingTouch(SeekBar seekBar) {

             

           }

          

           @Override

           public void onProgressChanged(SeekBar seekBar, int progress,

                  boolean fromUser) {

             

           }

       });

      

       //得到surfaceview

       sv = (SurfaceView) findViewById(R.id.sv);

       //得到显示界面内容的容器

       holder = sv.getHolder();

       //在低版本模拟器上运行记得加上下面的参数。不自己维护双缓冲区,而是等待多媒体播放框架主动的推送数据。

       holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

       holder.addCallback(new Callback() {

          

           @Override

           public void surfaceDestroyed(SurfaceHolder holder) {

              System.out.println("destoryed");

              if(mediaPlayer!=null&&mediaPlayer.isPlaying()){

                  position = mediaPlayer.getCurrentPosition();

                  mediaPlayer.stop();

                  mediaPlayer.release();

                  mediaPlayer = null;

                  timer.cancel();

                  task.cancel();

                  timer = null;

                  task = null;

              }

           }

          

           @Override

           public void surfaceCreated(SurfaceHolder holder) {

              System.out.println("created");

              if(position>0){//记录的有播放进度。

                  try {

                     mediaPlayer = new MediaPlayer();

                     mediaPlayer.setDataSource(filepath);//设置播放的数据源。

                      mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);

                     mediaPlayer.setDisplay(holder);

                     mediaPlayer.prepare();//准备开始播放 播放的逻辑是c代码在新的线程里面执行。

                     mediaPlayer.start();

                     mediaPlayer.seekTo(position);

                     bt_play.setEnabled(false);

                     mediaPlayer.setOnCompletionListener(new OnCompletionListener() {

                         @Override

                         public void onCompletion(MediaPlayer mp) {

                            bt_play.setEnabled(true);

                         }

                     });

                     int max = mediaPlayer.getDuration();

                     seekBar1.setMax(max);

                     timer = new Timer();

                     task = new TimerTask() {

                         @Override

                         public void run() {

                             seekBar1.setProgress(mediaPlayer.getCurrentPosition());

                         }

                     };

                     timer.schedule(task, 0, 500);

                  } catch (IOException e) {

                     e.printStackTrace();

                  }

              }

           }

          

           @Override

           public void surfaceChanged(SurfaceHolder holder, int format, int width,

                  int height) {

              System.out.println("changed");

           }

       });

    }

   

    /**

     * 播放

     * @param view

     */

    public void play(View view) {

       filepath = et_path.getText().toString().trim();

       File file = new File(filepath);

       if(file.exists()){

           try {

              mediaPlayer = new MediaPlayer();

              mediaPlayer.setDataSource(filepath);//设置播放的数据源。

               mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);

              mediaPlayer.setDisplay(holder);

              mediaPlayer.prepare();//准备开始播放 播放的逻辑是c代码在新的线程里面执行。

              mediaPlayer.start();

              //设置拖动进度条的最大值

              int max = mediaPlayer.getDuration();

              seekBar1.setMax(max);

              timer = new Timer();

              task = new TimerTask() {

                  @Override

                  public void run() {

                      seekBar1.setProgress(mediaPlayer.getCurrentPosition());

                  }

              };

              timer.schedule(task, 0, 500);

             

              bt_play.setEnabled(false);

              mediaPlayer.setOnCompletionListener(new OnCompletionListener() {

                  @Override

                  public void onCompletion(MediaPlayer mp) {

                     bt_play.setEnabled(true);

                  }

              });

           } catch (Exception e) {

              e.printStackTrace();

              Toast.makeText(this, "播放失败", 0).show();

           }

       }else{

           Toast.makeText(this, "文件不存在,请检查文件的路径", 0).show();

       }

    }

    /**

     * 暂停

     * @param view

     */

    public void pause(View view) {

       if("继续".equals(bt_pause.getText().toString())){

           mediaPlayer.start();

           bt_pause.setText("暂停");

           return;

       }

       if(mediaPlayer!=null&&mediaPlayer.isPlaying()){

           mediaPlayer.pause();

           bt_pause.setText("继续");

       }

    }

   

    /**

     * 停止

     * @param view

     */

    public void stop(View view) {

       if(mediaPlayer!=null&&mediaPlayer.isPlaying()){

           mediaPlayer.stop();

           mediaPlayer.release();

           mediaPlayer = null;

       }

       bt_pause.setText("暂停");

       bt_play.setEnabled(true);

    }

   

    /**

     * 重播

     * @param view

     */

    public void replay(View view) {

       if(mediaPlayer!=null&&mediaPlayer.isPlaying()){

           mediaPlayer.seekTo(0);

       }else{

           play(view);

       }

       bt_pause.setText("暂停");

    }

}

 

网络视频播放器,编写布局文件

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical"

    tools:context=".MainActivity" >

 

    <EditText

        android:id="@+id/et_path"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:hint="请输入要播放文件的路径"/>

 

    <LinearLayout

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:orientation="horizontal" >

 

        <Button

            android:id="@+id/bt_play"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:onClick="play"

            android:text="播放" />

 

        <Button

            android:id="@+id/bt_pause"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:onClick="pause"

            android:text="暂停" />

 

        <Button

            android:id="@+id/bt_stop"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:onClick="stop"

            android:text="停止" />

 

        <Button

            android:id="@+id/bt_replay"

            android:layout_width="0dip"

            android:layout_height="wrap_content"

            android:layout_weight="1"

            android:onClick="replay"

            android:text="重播" />

    </LinearLayout>

 

    <SurfaceView

        android:id="@+id/sv"

        android:layout_width="fill_parent"

        android:layout_height="fill_parent" />

 

</LinearLayout>

编写MainActivity

package com.itheima.musicplayer;

 

import java.io.File;

import java.io.IOException;

 

import android.app.Activity;

import android.media.AudioManager;

import android.media.MediaPlayer;

import android.media.MediaPlayer.OnCompletionListener;

import android.os.Bundle;

import android.view.SurfaceHolder;

import android.view.SurfaceHolder.Callback;

import android.view.SurfaceView;

import android.view.View;

import android.widget.Button;

import android.widget.EditText;

import android.widget.Toast;

 

public class MainActivity extends Activity {

    private EditText et_path;

   

    private MediaPlayer mediaPlayer;

   

    private Button bt_play,bt_pause,bt_stop,bt_replay;

   

    private SurfaceView sv;

    private SurfaceHolder holder;

   

    private int position;

    private String filepath;

 

    @Override

    protected void onCreate(Bundle savedInstanceState) {

       super.onCreate(savedInstanceState);

       setContentView(R.layout.activity_main);

       et_path = (EditText) findViewById(R.id.et_path);

       bt_play = (Button) findViewById(R.id.bt_play);

       bt_pause = (Button) findViewById(R.id.bt_pause);

       bt_stop = (Button) findViewById(R.id.bt_stop);

       bt_replay = (Button) findViewById(R.id.bt_replay);

       //得到surfaceview

       sv = (SurfaceView) findViewById(R.id.sv);

       //得到显示界面内容的容器

       holder = sv.getHolder();

       //在低版本模拟器上运行记得加上下面的参数。不自己维护双缓冲区,而是等待多媒体播放框架主动的推送数据。

       holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

       holder.addCallback(new Callback() {

          

           @Override

           public void surfaceDestroyed(SurfaceHolder holder) {

              System.out.println("destoryed");

              if(mediaPlayer!=null&&mediaPlayer.isPlaying()){

                  position = mediaPlayer.getCurrentPosition();

                  mediaPlayer.stop();

                  mediaPlayer.release();

                  mediaPlayer = null;

              }

           }

          

           @Override

           public void surfaceCreated(SurfaceHolder holder) {

              System.out.println("created");

              if(position>0){//记录的有播放进度。

                  try {

                     mediaPlayer = new MediaPlayer();

                     mediaPlayer.setDataSource(filepath);//设置播放的数据源。

                      mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);

                     mediaPlayer.setDisplay(holder);

                     mediaPlayer.prepare();//准备开始播放 播放的逻辑是c代码在新的线程里面执行。

                     mediaPlayer.start();

                     mediaPlayer.seekTo(position);

                     bt_play.setEnabled(false);

                     mediaPlayer.setOnCompletionListener(new OnCompletionListener() {

                         @Override

                         public void onCompletion(MediaPlayer mp) {

                            bt_play.setEnabled(true);

                         }

                     });

                  } catch (IOException e) {

                     e.printStackTrace();

                  }

              }

           }

          

           @Override

           public void surfaceChanged(SurfaceHolder holder, int format, int width,

                  int height) {

              System.out.println("changed");

           }

       });

      

    }

    /**

     * 播放

     * @param view

     */

    public void play(View view) {

       filepath = et_path.getText().toString().trim();

       //File file = new File(filepath);

       if(filepath.startsWith("http://")){

           try {

              mediaPlayer = new MediaPlayer();

               mediaPlayer.setDataSource(filepath);//设置播放的数据源。

               mediaPlayer.setAudioStreamType(AudioManager.STREAM_MUSIC);

              mediaPlayer.setDisplay(holder);

              mediaPlayer.prepare();//准备开始播放 播放的逻辑是c代码在新的线程里面执行。

              mediaPlayer.start();

              bt_play.setEnabled(false);

              mediaPlayer.setOnCompletionListener(new OnCompletionListener() {

                  @Override

                  public void onCompletion(MediaPlayer mp) {

                     bt_play.setEnabled(true);

                  }

              });

           } catch (Exception e) {

              e.printStackTrace();

              Toast.makeText(this, "播放失败", 0).show();

           }

       }else{

           Toast.makeText(this, "文件不存在,请检查文件的路径", 0).show();

       }

    }

    /**

     * 暂停

     * @param view

     */

    public void pause(View view) {

       if("继续".equals(bt_pause.getText().toString())){

           mediaPlayer.start();

           bt_pause.setText("暂停");

           return;

       }

       if(mediaPlayer!=null&&mediaPlayer.isPlaying()){

           mediaPlayer.pause();

           bt_pause.setText("继续");

       }

    }

    /**

     * 停止

     * @param view

     */

    public void stop(View view) {

       if(mediaPlayer!=null&&mediaPlayer.isPlaying()){

           mediaPlayer.stop();

           mediaPlayer.release();

           mediaPlayer = null;

       }

       bt_pause.setText("暂停");

       bt_play.setEnabled(true);

    }

    /**

     * 重播

     * @param view

     */

    public void replay(View view) {

       if(mediaPlayer!=null&&mediaPlayer.isPlaying()){

           mediaPlayer.seekTo(0);

       }else{

           play(view);

       }

       bt_pause.setText("暂停");

    }

 

}

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="com.itheima.musicplayer"

    android:versionCode="1"

    android:versionName="1.0" >

 

    <uses-sdk

        android:minSdkVersion="8"

        android:targetSdkVersion="19" />

    <!-- 注意如果涉及到网络的都要添加上下面的一句 -->

    <uses-permission android:name="android.permission.INTERNET"/>

 

    <application

        android:allowBackup="true"

        android:icon="@drawable/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme" >

        <activity

            android:name="com.itheima.musicplayer.MainActivity"

            android:label="@string/app_name" >

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

 

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

    </application>

 

</manifest>

 

照相机引用,如果想使用模拟器进行拍照,需要制定模拟器的一个设置,设置如下图:

编写以下案例,当点击拍照之后弹出权限提示框。

1 编写布局文件activity_main.xml,代码如下:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical"

    tools:context=".MainActivity" >

 

    <Button

        android:onClick="click"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:text="拍照" />

   

    <ImageView

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:id="@+id/iv"/>

   

</LinearLayout>

1 MainActivity的代码如下:

package com.itheima.camera;

 

import java.io.File;

 

import android.app.Activity;

import android.content.Intent;

import android.net.Uri;

import android.os.Bundle;

import android.os.Environment;

import android.provider.MediaStore;

import android.util.Log;

import android.view.View;

import android.widget.ImageView;

 

/**

 * 拍照的实例代码

 * @author toto

 */

public class MainActivity extends Activity {

         private ImageView iv;

         private File file;

        

         @Override

         protected void onCreate(Bundle savedInstanceState) {

                   super.onCreate(savedInstanceState);

                   setContentView(R.layout.activity_main);

                  

                   iv = (ImageView) findViewById(R.id.iv);

         }

        

         /**

          * 当点击之后的效果

          * @param view

          */

         public void click(View view) {

                   Intent intent = new Intent();

                   //指定拍照的意图ACTION_IMAGE_CAPTURE,如果是录像的可以用ACTION_VIDEO_CAPTURE,并且将文件后缀改成.3gp

                   intent.setAction(MediaStore.ACTION_IMAGE_CAPTURE);

                   Log.i("FILE-PATH", Environment.getExternalStorageDirectory().toString());

                   //第一个参数是文件路径,第二个参数表示的是文件名称

                   file =  new File(Environment.getExternalStorageDirectory(),System.currentTimeMillis()+".jpg");

                   //指定保存文件的路径

                   intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(file));

                   //开启一个新的action,并且获得其返回值

                   startActivityForResult(intent, 100);

         }

        

         /**

          * startActivityForResult返回结果的时候会执行下面的函数

          */

         @Override

         protected void onActivityResult(int requestCode, int resultCode, Intent data) {

                   if (resultCode == 100) {

                            iv.setImageURI(Uri.fromFile(file));

                   }

                   super.onActivityResult(requestCode, resultCode, data);

         }

}

若是手机,例如我的手机,存储在/sdcard/emulated/0中。

===============================================================================

偷拍的案例,编写如下案例(将下面的图片显示区域变得很小可以实现偷拍功能):

1 编写布局文件activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:orientation="vertical"

    android:layout_height="match_parent"

    tools:context=".MainActivity" >

 

    <Button

        android:onClick="click"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content"

        android:text="拍照"/>

   

    <FrameLayout

         android:id="@+id/camera_preview"

         android:layout_width="100dip"

         android:layout_height="100dip"/>

   

    <ImageView

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:id="@+id/iv"/>

   

</LinearLayout>

2 CameraPreview的代码如下:

package com.itheima.camera2;

 

import java.io.IOException;

 

import android.content.Context;

import android.hardware.Camera;

import android.util.Log;

import android.view.SurfaceHolder;

import android.view.SurfaceView;

 

/** A basic Camera preview class */

public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {

    private static final String TAG = "CameraPreview";

    private SurfaceHolder mHolder;

    private Camera mCamera;

 

    @SuppressWarnings("deprecation")

    public CameraPreview(Context context, Camera camera) {

        super(context);

        mCamera = camera;

 

        // Install a SurfaceHolder.Callback so we get notified when the

        // underlying surface is created and destroyed.

        mHolder = getHolder();

        mHolder.addCallback(this);

        // deprecated setting, but required on Android versions prior to 3.0

        mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);

    }

 

    public void surfaceCreated(SurfaceHolder holder) {

        // The Surface has been created, now tell the camera where to draw the preview.

        try {

            mCamera.setPreviewDisplay(holder);

            mCamera.startPreview();

        } catch (IOException e) {

            Log.d(TAG, "Error setting camera preview: " + e.getMessage());

        }

    }

 

    public void surfaceDestroyed(SurfaceHolder holder) {

        // empty. Take care of releasing the Camera preview in your activity.

    }

 

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {

        // If your preview can change or rotate, take care of those events here.

        // Make sure to stop the preview before resizing or reformatting it.

 

        if (mHolder.getSurface() == null){

          // preview surface does not exist

          return;

        }

 

        // stop preview before making changes

        try {

            mCamera.stopPreview();

        } catch (Exception e){

          // ignore: tried to stop a non-existent preview

        }

 

        // set preview size and make any resize, rotate or

        // reformatting changes here

 

        // start preview with new settings

        try {

            mCamera.setPreviewDisplay(mHolder);

            mCamera.startPreview();

 

        } catch (Exception e){

            Log.d(TAG, "Error starting camera preview: " + e.getMessage());

        }

    }

}

  1. MainActivity的代码如下:

package com.itheima.camera2;

 

import java.io.File;

import java.io.FileOutputStream;

 

import android.app.Activity;

import android.hardware.Camera;

import android.hardware.Camera.AutoFocusCallback;

import android.hardware.Camera.PictureCallback;

import android.os.Bundle;

import android.os.SystemClock;

import android.view.View;

import android.widget.FrameLayout;

import android.widget.ImageView;

import android.widget.Toast;

 

public class MainActivity extends Activity {

    private ImageView iv;

    private Camera mCamera;

    private CameraPreview mPreview;

 

    @Override

    protected void onCreate(Bundle savedInstanceState) {

       super.onCreate(savedInstanceState);

       setContentView(R.layout.activity_main);

       iv = (ImageView) findViewById(R.id.iv);

        // Create an instance of Camera

        mCamera = getCameraInstance();

        // Create our Preview view and set it as the content of our activity.

        mPreview = new CameraPreview(this, mCamera);

        FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);

        preview.addView(mPreview);

    }

   

    public void click(View view){

       mCamera.autoFocus(new AutoFocusCallback() {

           @Override

           public void onAutoFocus(boolean success, Camera camera) {

              mCamera.takePicture(null, null, new PictureCallback() {

                  @Override

                  public void onPictureTaken(byte[] data, Camera camera) {

                     try {

                         //File file = new File(Environment.getExternalStorageDirectory(),SystemClock.uptimeMillis()+".jpg");

                         File file = new File("/mnt/sdcard2",SystemClock.uptimeMillis()+".jpg");

                         FileOutputStream fos = new FileOutputStream(file);

                         fos.write(data);

                         fos.close();

                         Toast.makeText(getApplicationContext(), "成功", 0).show();

                         mCamera.startPreview();

                     } catch (Exception e) {

                         e.printStackTrace();

                     }

                  }

              });

           }

       });

      

       

    }

   

    /** 获取一个照相机实例 */

    public static Camera getCameraInstance(){

        Camera c = null;

        try {

            c = Camera.open(); // attempt to get a Camera instance

        }

        catch (Exception e){

            // Camera is not available (in use or does not exist)

        }

        return c; // returns null if camera is unavailable

    }

   

    @Override

    protected void onDestroy() {

       mCamera.stopPreview();

       mCamera.release();

       mCamera = null;

       super.onDestroy();

    }

}

  1. 编写AndroidManifest.xml的清单文件,代码如下:

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="com.itheima.camera2"

    android:versionCode="1"

    android:versionName="1.0" >

 

    <uses-sdk

        android:minSdkVersion="8"

        android:targetSdkVersion="19" />

   

   <uses-permission android:name="android.permission.CAMERA" />

    <uses-feature android:name="android.hardware.camera" />

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

 

    <application

        android:allowBackup="true"

        android:icon="@drawable/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme" >

        <activity

            android:name="com.itheima.camera2.MainActivity"

            android:label="@string/app_name" >

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

 

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

    </application>

 

</manifest>

 



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