Android自定义相机,切换前后摄像头,照相机拍照

Android自定义相机,简单实现切换前后摄像头,照相机拍照 
Ctrl +C  Ctrl+V 可以直接 run 起来,注释比较详细;源码下载

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.tomorrow_p.camera_p">

<!-- 调用摄像头权限 -->
<uses-permission android:name="android.permission.CAMERA" />
<!-- 挂载sd卡 -->
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
<!-- sd卡读写权限 -->
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

<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>
<activity android:name="com.tomorrow_p.camera_p.PreviewImageActivity"></activity>
</application>

</manifest>

android6.0及以上需要 动态申请相机权限:
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA}, 1);
}
package com.tomorrow_p.camera_p;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.ViewGroup;
import android.view.WindowManager;
import android.widget.Toast;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;

public class MainActivity extends Activity {
private static final String TAG = "ansen";
private View mRelativeLayout;
private Camera mCamera;
private Camera.Parameters mParameters = null;
private int cameraPosition = 1;//0代表前置摄像头，1代表后置摄像头
private SurfaceHolder mHolder;

Bundle bundle = null; // 声明一个Bundle对象，用来存储数据

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// requestWindowFeature(Window.FEATURE_NO_TITLE);//没有标题
// this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);//设置全屏
// this.getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);//拍照过程屏幕一直处于高亮

setContentView(R.layout.activity_main);

mRelativeLayout = findViewById(R.id.relativeLayout);
SurfaceView surfaceView = (SurfaceView) findViewById(R.id.surfaceView);

surfaceView.getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
surfaceView.getHolder().setFixedSize(176, 144); //设置Surface分辨率
surfaceView.getHolder().setKeepScreenOn(true);// 屏幕常亮
surfaceView.getHolder().addCallback(new SurfaceCallback());//为SurfaceView的句柄添加一个回调函数
}

public void takePhoto(View v) {
if (mCamera != null) {
// 获取到拍照的图片数据后回调PictureCallback,PictureCallback可以对相片进行保存或传入网络
mCamera.takePicture(null, null, new MyPictureCallback());
}
}

public void change(View v) {
//切换前后摄像头
int cameraCount = 0;
Camera.CameraInfo cameraInfo = new Camera.CameraInfo();
cameraCount = Camera.getNumberOfCameras();//得到摄像头的个数

for (int i = 0; i < cameraCount; i++) {
Camera.getCameraInfo(i, cameraInfo);//得到每一个摄像头的信息
if (cameraPosition == 1) {
//现在是后置，变更为前置
if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {//代表摄像头的方位，CAMERA_FACING_FRONT前置 CAMERA_FACING_BACK后置
mCamera.stopPreview();//停掉原来摄像头的预览
mCamera.release();//释放资源
mCamera = null;//取消原来摄像头
mCamera = Camera.open(i);//打开当前选中的摄像头
try {
mCamera.setPreviewDisplay(mHolder);//通过surfaceview显示取景画面
} catch (IOException e) {
e.printStackTrace();
}
mCamera.startPreview();//开始预览
cameraPosition = 0;
break;
}
} else {
//现在是前置， 变更为后置
if (cameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_BACK) {//代表摄像头的方位，CAMERA_FACING_FRONT前置 CAMERA_FACING_BACK后置
mCamera.stopPreview();//停掉原来摄像头的预览
mCamera.release();//释放资源
mCamera = null;//取消原来摄像头
mCamera = Camera.open(i);//打开当前选中的摄像头
try {
mCamera.setPreviewDisplay(mHolder);//通过surfaceview显示取景画面
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
mCamera.startPreview();//开始预览
cameraPosition = 1;
break;
}
}

}
}

/**
* 图片被点击触发的时间
*
* @param v
*/
public void imageClick(View v) {
if (bundle == null) {
Toast.makeText(getApplicationContext(), "没有数据", Toast.LENGTH_SHORT).show();
} else {
Intent intent = new Intent(this, PreviewImageActivity.class);
intent.putExtras(bundle);
startActivity(intent);
}
}

private final class MyPictureCallback implements Camera.PictureCallback {

@Override
public void onPictureTaken(byte[] data, Camera camera) {
try {
bundle = new Bundle();
bundle.putByteArray("bytes", data); //将图片字节数据保存在bundle当中，实现数据交换
saveToSDCard(data); // 保存图片到sd卡中
Toast.makeText(getApplicationContext(), "success", Toast.LENGTH_SHORT).show();
// camera.startPreview(); // 拍完照后，重新开始预览

} catch (Exception e) {
e.printStackTrace();
}
}
}

public void saveToSDCard(byte[] data) throws IOException {
Log.d(TAG, "saveToSDCard");
Date date = new Date();
SimpleDateFormat format = new SimpleDateFormat("yyyyMMddHHmmss"); // 格式化时间
String filename = format.format(date) + ".jpg";
File fileFolder = new File(Environment.getExternalStorageDirectory() + "/ansen/");// Environment.getRootDirectory()
if (!fileFolder.exists()) {
fileFolder.mkdir();
}
File jpgFile = new File(fileFolder, filename);
FileOutputStream outputStream = new FileOutputStream(jpgFile); // 文件输出流
outputStream.write(data);
outputStream.close();
mCamera.startPreview(); // 拍完照后，重新开始预览
if (false) {
Bitmap b = byteToBitmap(data);
// 获取手机屏幕的宽高
WindowManager windowManager = (WindowManager) getSystemService(Context.WINDOW_SERVICE);
int windowWidth = windowManager.getDefaultDisplay().getWidth();
int windowHight = windowManager.getDefaultDisplay().getHeight();
Bitmap bitmap = Bitmap.createBitmap(b, 0, 0, windowWidth, windowHight);
// 图片压缩
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, outputStream);
outputStream.flush();

}
}

/**
* 把图片byte流转换成bitmap
*/
private Bitmap byteToBitmap(byte[] data) {
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
Bitmap b = BitmapFactory.decodeByteArray(data, 0, data.length, options);
int i = 0;
while (true) {
if ((options.outWidth >> i <= 1000)
&& (options.outHeight >> i <= 1000)) {
options.inSampleSize = (int) Math.pow(2.0D, i);
options.inJustDecodeBounds = false;
b = BitmapFactory.decodeByteArray(data, 0, data.length, options);
break;
}
i += 1;
}
return b;
}

/**
* 显示surfaceView 数据的接口
*/
private class SurfaceCallback implements SurfaceHolder.Callback {

@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
Log.d(TAG, "surfaceChanged");
mParameters = mCamera.getParameters(); // 获取各项参数
mParameters.setPictureFormat(PixelFormat.JPEG); // 设置图片格式
mParameters.setPreviewSize(width, height); // 设置预览大小
mParameters.setPreviewFrameRate(5); //设置每秒显示4帧
mParameters.setPictureSize(width, height); // 设置保存的图片尺寸
mParameters.setJpegQuality(80); // 设置照片质量
}

@Override
public void surfaceCreated(SurfaceHolder holder) {
Log.d(TAG, "surfaceCreated");
mHolder = holder;// SurfaceHolder是系统提供用来设置surfaceView的对象
try {
mCamera = Camera.open(); // 打开摄像头
mCamera.setPreviewDisplay(holder); //通过surfaceview显示取景画面
mCamera.setDisplayOrientation(getPreviewDegree(MainActivity.this));// 设置相机的方向
mCamera.startPreview(); // 开始预览
} catch (Exception e) {
e.printStackTrace();
Log.e(TAG, "surfaceCreated >> Exception: " + e.getMessage());
}

}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {
Log.d(TAG, "surfaceDestroyed");
if (mCamera != null) {
mCamera.release(); // 释放照相机
mCamera = null;
}
}
}

/**
* 点击手机屏幕是，显示两个按钮
*/
@Override
public boolean onTouchEvent(MotionEvent event) {
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
mRelativeLayout.setVisibility(ViewGroup.VISIBLE); // 设置视图可见
break;
}
return true;
}

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
switch (keyCode) {
case KeyEvent.KEYCODE_CAMERA:
if (mCamera != null && event.getRepeatCount() == 0) {
// 获取到拍照的图片数据后回调PictureCallback,PictureCallback可以对相片进行保存或传入网络
mCamera.takePicture(null, null, new MyPictureCallback());
}
}
return super.onKeyDown(keyCode, event);
}

// 用于根据手机方向获得相机预览画面旋转的角度
public static int getPreviewDegree(Activity activity) {
int degree = 0;
// 获得手机的方向
int rotation = activity.getWindowManager().getDefaultDisplay().getRotation();
Log.d(TAG, "rotation : " + rotation);
// 根据手机的方向计算相机预览画面应该选择的角度
switch (rotation) {
case Surface.ROTATION_0:
degree = 90;
break;
case Surface.ROTATION_90:
degree = 0;
break;
case Surface.ROTATION_180:
degree = 270;
break;
case Surface.ROTATION_270:
degree = 180;
break;
}
return degree;
}
}
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout 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"
tools:context="com.tomorrow_p.camera_p.MainActivity">

<SurfaceView
android:id="@+id/surfaceView"
android:layout_width="match_parent"
android:layout_height="match_parent" />

<LinearLayout
android:id="@+id/relativeLayout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:visibility="gone">

<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="change"
android:text="切换" />

<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="takePhoto"
android:text="拍照" />

<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="imageClick"
android:text="预览" />

</LinearLayout>
</FrameLayout>

package com.tomorrow_p.camera_p;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.os.Bundle;
import android.widget.ImageView;

public class PreviewImageActivity extends Activity {
private ImageView ivPic = null; // 显示图片控件

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.preview_image);
ivPic = (ImageView) findViewById(R.id.imageView);
setImageBitmap(getImageFormBundle());
}

public void setImageBitmap(byte[] bytes) {
Bitmap cameraBitmap = byte2Bitmap();
// 根据拍摄的方向旋转图像（纵向拍摄时要需要将图像选择90度)
Matrix matrix = new Matrix();
matrix.setRotate(MainActivity.getPreviewDegree(this));
cameraBitmap = Bitmap
.createBitmap(cameraBitmap, 0, 0, cameraBitmap.getWidth(),
cameraBitmap.getHeight(), matrix, true);
ivPic.setImageBitmap(cameraBitmap);
}

public byte[] getImageFormBundle() {
Intent intent = getIntent();
Bundle data = intent.getExtras();
byte[] bytes = data.getByteArray("bytes");
return bytes;
}

/**
* 将字节数组的图形数据转换为Bitmap
*/
private Bitmap byte2Bitmap() {
byte[] data = getImageFormBundle();
// 将byte数组转换成Bitmap对象
Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
return bitmap;
}
}