Android手机拍照

参考的这个视频教程：http://v.youku.com/v_show/id_XNjI5MzkzMjQ4.html和官方API档file:///D:/Android/androidstudio/sdk/docs/guide/topics/media/camera.html

java程序

 package com.example.x_yp.system_camera;

 import java.io.File;
 import java.io.FileOutputStream;

 import android.os.Bundle;
 import android.util.Log;
 import android.view.View;
 import android.widget.Button;
 import android.widget.FrameLayout;
 import android.app.Activity;
 import android.content.Context;
 import android.content.pm.PackageManager;
 import android.hardware.Camera;
 import android.hardware.Camera.AutoFocusCallback;
 import android.hardware.Camera.PictureCallback;

 public class MainActivity extends Activity {
     protected static final String TAG = "main";
     private Camera mCamera;
     private CameraPreview mPreview;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);

         mCamera = getCameraInstance();

         // 创建预览类，并与Camera关联，最后添加到界面布局中
         mPreview = new CameraPreview(this, mCamera);
         FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);
         preview.addView(mPreview);

         Button captureButton = (Button) findViewById(R.id.button_capture);
         captureButton.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
                 // 在捕获图片前进行自动对焦
                 mCamera.autoFocus(new AutoFocusCallback() {

                     @Override
                     public void onAutoFocus(boolean success, Camera camera) {
                         // 从Camera捕获图片
                         mCamera.takePicture(null, null, mPicture);
                     }
                 });
             }
         });
     }

     /** 检测设备是否存在Camera硬件 */
     private boolean checkCameraHardware(Context context) {
         if (context.getPackageManager().hasSystemFeature(
                 PackageManager.FEATURE_CAMERA)) {
             // 存在
             return true;
         } else {
             // 不存在
             return false;
         }
     }

     /** 打开一个Camera */
     public static Camera getCameraInstance() {
         Camera c = null;
         try {
             c = Camera.open();
         } catch (Exception e) {
             Log.d(TAG, "打开Camera失败失败");
         }
         return c;
     }

     private PictureCallback mPicture = new PictureCallback() {

         @Override
         public void onPictureTaken(byte[] data, Camera camera) {
             // 获取Jpeg图片，并保存在sd卡上
             File pictureFile = new File("/sdcard/" + System.currentTimeMillis() + ".jpg");
             try {
                 FileOutputStream fos = new FileOutputStream(pictureFile);
                 fos.write(data);
                 fos.close();
             } catch (Exception e) {
                 Log.d(TAG, "保存图片失败");
             }
         }
     };

     @Override
     protected void onDestroy() {
         // 回收Camera资源
         if(mCamera!=null){
             mCamera.stopPreview();
             mCamera.release();
             mCamera=null;
         }
         super.onDestroy();
     }

 }

package com.example.x_yp.system_camera;
import java.io.IOException;
import android.content.Context;
import android.hardware.Camera;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

/**
 * 定义一个预览类
 */
public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback {
    private static final String TAG = "main";
    private SurfaceHolder mHolder;
    private Camera mCamera;

    public CameraPreview(Context context, Camera camera) {
        super(context);
        mCamera = camera;

        // 通过SurfaceView获得SurfaceHolder
        mHolder = getHolder();
        // 为SurfaceHolder指定回调
        mHolder.addCallback(this);
        // 设置Surface不维护自己的缓冲区，而是等待屏幕的渲染引擎将内容推送到界面 在Android3.0之后弃用
        mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    public void surfaceCreated(SurfaceHolder holder) {
        // 当Surface被创建之后，开始Camera的预览
        try {
            mCamera.setPreviewDisplay(holder);
            mCamera.startPreview();
        } catch (IOException e) {
            Log.d(TAG, "预览失败");
        }
    }

    public void surfaceDestroyed(SurfaceHolder holder) {

    }

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        // Surface发生改变的时候将被调用，第一次显示到界面的时候也会被调用
        if (mHolder.getSurface() == null){
          // 如果Surface为空，不继续操作
          return;
        }

        // 停止Camera的预览
        try {
            mCamera.stopPreview();
        } catch (Exception e){
            Log.d(TAG, "当Surface改变后，停止预览出错");
        }

        // 在预览前可以指定Camera的各项参数

        // 重新开始预览
        try {
            mCamera.setPreviewDisplay(mHolder);
            mCamera.startPreview();

        } catch (Exception e){
            Log.d(TAG, "预览Camera出错");
        }
    }
}

布局文件

<?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"
    >
    <FrameLayout
        android:id="@+id/camera_preview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_weight="1"
        />

    <Button
        android:id="@+id/button_capture"
        android:text="Capture"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        />
</LinearLayout>

权限设置

 <uses-permission android:name="android.permission.CAMERA" />
    <uses-feature android:name="android.hardware.camera" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.RECORD_AUDIO" />
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />