Android学习之简单的拍照功能

本博客源码：Android学习之简单的拍照功能      http://download.csdn.net/detail/bq1073100909/7721211 
本代码里面有详细注释，就不再进行讲解，按照步骤一步一步来，并不难懂。

图片保存路径因手机不同而不同，我没有使用系统提供的接口来获取路径，而是使用我手机的/mnt/sdcard2，推荐使用系统提供的接口，在前面的Android博客里面已经使用。

CameraDemo.java

代码：

[java] view plain copy

package org.dyb.camera;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.Matrix;
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.hardware.Camera.AutoFocusCallback;
import android.hardware.Camera.PictureCallback;
import android.hardware.Camera.ShutterCallback;
import android.os.Bundle;
import android.util.Log;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.view.ViewGroup.LayoutParams;
import android.view.Window;
import android.view.WindowManager;
import android.widget.ImageButton;
import android.widget.Toast;

public class CameraDemo extends Activity implements SurfaceHolder.Callback {

private SurfaceView mPreviewSV = null; //预览SurfaceView
private SurfaceHolder mySurfaceHolder = null;
private AutoFocusCallback myAutoFocusCallback = null;
private ImageButton mPhotoImgBtn = null;
private Camera myCamera = null;
private boolean isPreview = false;
private Bitmap mBitmap = null;
private String tag="camera";

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//设置全屏无标题
requestWindowFeature(Window.FEATURE_NO_TITLE);
Window myWindow = this.getWindow();
int flag = WindowManager.LayoutParams.FLAG_FULLSCREEN;
myWindow.setFlags(flag, flag);

setContentView(R.layout.activity_photo);

//初始化SurfaceView
mPreviewSV = (SurfaceView)findViewById(R.id.previewSV);
mySurfaceHolder = mPreviewSV.getHolder();
mySurfaceHolder.setFormat(PixelFormat.TRANSLUCENT);//translucent半透明 transparent透明
mySurfaceHolder.addCallback(this);
mySurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
//自动聚焦变量回调
myAutoFocusCallback = new AutoFocusCallback() {
@Override
public void onAutoFocus(boolean success, Camera camera) {
if(success)//success表示对焦成功
{
Toast.makeText(getApplicationContext(), "autofocus success", Toast.LENGTH_SHORT).show();
}
else
{
Toast.makeText(getApplicationContext(), "autofocus false", Toast.LENGTH_SHORT).show();
}

}
};

mPhotoImgBtn = (ImageButton)findViewById(R.id.photoImgBtn);
//手动设置拍照ImageButton的大小为120×120,原图片大小是64×64
LayoutParams lp = mPhotoImgBtn.getLayoutParams();
lp.width = 120;
lp.height = 120;
mPhotoImgBtn.setLayoutParams(lp);
mPhotoImgBtn.setOnClickListener(new PhotoOnClickListener());
mPhotoImgBtn.setOnTouchListener(new MyOnTouchListener());
}

// SurfaceView启动时/初次实例化，预览界面被创建时，该方法被调用。
@Override
public void surfaceCreated(SurfaceHolder holder) {
myCamera = Camera.open();
try {
myCamera.setPreviewDisplay(mySurfaceHolder);
} catch (IOException e) {
if(null != myCamera){
myCamera.release();
myCamera = null;
}
e.printStackTrace();
}
}

// 当SurfaceView/预览界面的格式和大小发生改变时，该方法被调用
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
// TODO Auto-generated method stub
initCamera();
}

private void initCamera() {
if(isPreview){
myCamera.stopPreview();
}

if(myCamera != null){
Camera.Parameters myParam = myCamera.getParameters();
//          //查询屏幕的宽和高
//          WindowManager wm = (WindowManager)getSystemService(Context.WINDOW_SERVICE);
//          Display display = wm.getDefaultDisplay();
//          Log.i(tag, "屏幕宽度："+display.getWidth()+" 屏幕高度:"+display.getHeight());
myParam.setPictureFormat(PixelFormat.JPEG);//设置拍照后存储的图片格式
//查询camera支持的picturesize和previewsize
//          List<Size> pictureSizes = myParam.getSupportedPictureSizes();
//          List<Size> previewSizes = myParam.getSupportedPreviewSizes();
//          for(int i=0; i<pictureSizes.size(); i++){
//              Size size = pictureSizes.get(i);
//              Log.i(tag, "initCamera:摄像头支持的pictureSizes: width = "+size.width+"height = "+size.height);
//          }
//          for(int i=0; i<previewSizes.size(); i++){
//              Size size = previewSizes.get(i);
//              Log.i(tag, "initCamera:摄像头支持的previewSizes: width = "+size.width+"height = "+size.height);
//
//          }
//设置大小和方向等参数
myParam.setPictureSize(1280, 960);
myParam.setPreviewSize(960, 720);
//myParam.set("rotation", 90);
myCamera.setDisplayOrientation(90);
myParam.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO);
myCamera.setParameters(myParam);
myCamera.startPreview();
myCamera.autoFocus(myAutoFocusCallback);
isPreview = true;
}
}

//销毁时被调用
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
// TODO Auto-generated method stub
Log.i(tag, "SurfaceHolder.Callback：Surface Destroyed");
if(null != myCamera){
myCamera.setPreviewCallback(null); /*在启动PreviewCallback时这个必须在前不然退出出错。这里实际上注释掉也没关系*/
myCamera.stopPreview();
isPreview = false;
myCamera.release();
myCamera = null;
}
}

private class PhotoOnClickListener implements OnClickListener{

@Override
public void onClick(View v) {
if(isPreview && myCamera!=null){
myCamera.takePicture(myShutterCallback, null, myJpegCallback);
}
}

}
/*为了使图片按钮按下和弹起状态不同，采用过滤颜色的方法.按下的时候让图片颜色变淡*/
public class MyOnTouchListener implements OnTouchListener{

public final  float[] BT_SELECTED=new float[]
{ 2, 0, 0, 0, 2,
0, 2, 0, 0, 2,
0, 0, 2, 0, 2,
0, 0, 0, 1, 0 };

public final float[] BT_NOT_SELECTED=new float[]
{ 1, 0, 0, 0, 0,
0, 1, 0, 0, 0,
0, 0, 1, 0, 0,
0, 0, 0, 1, 0 };
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
if(event.getAction() == MotionEvent.ACTION_DOWN){
v.getBackground().setColorFilter(new ColorMatrixColorFilter(BT_SELECTED));
v.setBackgroundDrawable(v.getBackground());
}
else if(event.getAction() == MotionEvent.ACTION_UP){
v.getBackground().setColorFilter(new ColorMatrixColorFilter(BT_NOT_SELECTED));
v.setBackgroundDrawable(v.getBackground());

}
return false;
}

}

/*为了实现拍照的快门声音及拍照保存照片需要下面三个回调变量*/
ShutterCallback myShutterCallback = new ShutterCallback()
//快门按下的回调，在这里我们可以设置类似播放“咔嚓”声之类的操作。默认的就是咔嚓。
{

public void onShutter() {
// TODO Auto-generated method stub
Log.i(tag, "myShutterCallback:onShutter...");

}
};
PictureCallback myRawCallback = new PictureCallback()
// 拍摄的未压缩原数据的回调,可以为null
{

public void onPictureTaken(byte[] data, Camera camera) {
// TODO Auto-generated method stub
Log.i(tag, "myRawCallback:onPictureTaken...");

}
};
PictureCallback myJpegCallback = new PictureCallback()
//对jpeg图像数据的回调,最重要的一个回调
{

public void onPictureTaken(byte[] data, Camera camera) {
// TODO Auto-generated method stub
Log.i(tag, "myJpegCallback:onPictureTaken...");
if(null != data){
mBitmap = BitmapFactory.decodeByteArray(data, 0, data.length);//data是字节数据，将其解析成位图
myCamera.stopPreview();
isPreview = false;
}
//设置FOCUS_MODE_CONTINUOUS_VIDEO)之后，myParam.set("rotation", 90)失效。图片竟然不能旋转了，故这里要旋转下
Matrix matrix = new Matrix();
matrix.postRotate((float)90.0);
Bitmap rotaBitmap = Bitmap.createBitmap(mBitmap, 0, 0, mBitmap.getWidth(), mBitmap.getHeight(), matrix, false);
//保存图片到sdcard
if(null != rotaBitmap)
{
saveJpeg(rotaBitmap);
}
//再次进入预览
myCamera.startPreview();
isPreview = true;
}

private void saveJpeg(Bitmap rotaBitmap) {
String savePath = "/mnt/sdcard2/rectPhoto/";
File folder = new File(savePath);
if(!folder.exists()) //如果文件夹不存在则创建
{
folder.mkdir();
}
long dataTake = System.currentTimeMillis();
String jpegName = savePath + dataTake +".jpg";
Log.i(tag, "saveJpeg:jpegName--" + jpegName);
//File jpegFile = new File(jpegName);
try {
FileOutputStream fout = new FileOutputStream(jpegName);
BufferedOutputStream bos = new BufferedOutputStream(fout);

//          //如果需要改变大小(默认的是宽960×高1280),如改成宽600×高800
//          Bitmap newBM = rotaBitmap.createScaledBitmap(rotaBitmap, 600, 800, false);

rotaBitmap.compress(Bitmap.CompressFormat.JPEG, 100, bos);
bos.flush();
bos.close();
Log.i(tag, "saveJpeg：存储完毕！");
} catch (IOException e) {
// TODO Auto-generated catch block
Log.i(tag, "saveJpeg:存储失败！");
e.printStackTrace();
}
}
};

@Override
public void onBackPressed()
//无意中按返回键时要释放内存
{
// TODO Auto-generated method stub
super.onBackPressed();
CameraDemo.this.finish();
}

}

activity_photo.xml布局文件代码：

[html] view plain copy

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/wish"
tools:context=".RectPhoto" />
<FrameLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
>

<SurfaceView
android:id="@+id/previewSV"
android:layout_width="fill_parent"
android:layout_height="800px"/>

</FrameLayout>

<ImageButton
android:id="@+id/photoImgBtn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/photo_img_btn"
android:layout_gravity="center" />

</LinearLayout>

全局配置文件：

AndroidManifest.xml

[html] view plain copy

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="org.dyb.camera"
android:versionCode="1"
android:versionName="1.0" >

<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="18" />

<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".CameraDemo"
android:label="@string/title_activity_rect_photo" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>

</application>
<!-- 增加文件存储和访问摄像头的权限 -->
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
</manifest>