安卓高级8 SurfaceView案例二 自定义相机

package qianfeng.com.customcamera;

import android.hardware.Camera;
import android.os.Bundle;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;

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

public class MainActivity extends AppCompatActivity implements SurfaceHolder.Callback {

private SurfaceView surfaceView;
private SurfaceHolder holder;
private Camera camera;
private byte[] bitmap_byte;
private int flag = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
surfaceView = (SurfaceView) findViewById(R.id.camera_sv);

holder = surfaceView.getHolder();
//设置 Holder 的类型 表示内容 表示内容为空由其他提供
holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
holder.addCallback(this);

//        实例化Camera     参数表示   0：  后置摄像头  1：前置摄像头
camera = Camera.open(flag);
// 按照顺时针方向旋转90度
camera.setDisplayOrientation(90);
//         获取一共有多少个摄像头
//        Camera.getNumberOfCameras();
}

public void onClick(View view) {
switch (view.getId()) {
case R.id.take_bt:
/*
参数1： 捕捉画面回调
参数2：原声图片回调
参数3： 处理过后的图片回调
*/
camera.takePicture(null, null, new Camera.PictureCallback() {
@Override
public void onPictureTaken(byte[] data, Camera camera) {
//停止预览
camera.stopPreview();
// 记录图片数据
bitmap_byte = data;
}
});
break;
case R.id.cancel_bt:
//取消
bitmap_byte = null;
// 开启预览
camera.startPreview();
break;
case R.id.save_bt:
// 保存
saveToSd();
break;
case R.id.change_bt:
// 切换前后摄像头
//先释放
camera.stopPreview();
camera.release();
camera = null;

// 切换摄像头标记     与当前的标记相反即可
if (flag == 1)
flag = 0;
else if (flag == 0)
flag = 1;

// 重新开启相机
camera = Camera.open(flag);
camera.setDisplayOrientation(90);
try {
camera.setPreviewDisplay(holder);
camera.startPreview();
} catch (IOException e) {
e.printStackTrace();
}
break;
}
}

// 保存图片到SD卡
private void saveToSd() {
String filPath = null;
if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
filPath = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator + "xixi.png";
}
try {
FileOutputStream out = new FileOutputStream(filPath);
out.write(bitmap_byte, 0, bitmap_byte.length);
out.flush();
out.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}

@Override
public void surfaceCreated(SurfaceHolder holder) {
if (camera != null) {
try {
//  提供预览画面
camera.setPreviewDisplay(holder);
// 开启预览
camera.startPreview();
} catch (IOException e) {
e.printStackTrace();
}
}
}

@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {
if (camera != null) {
// 销毁的时候停止预览
camera.stopPreview();
}
}
}

<?xml version="1.0" encoding="utf-8"?>
<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="qianfeng.com.customcamera.MainActivity">

<SurfaceView
android:id="@+id/camera_sv"
android:layout_width="match_parent"
android:layout_height="400dp" />

<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">

<Button
android:id="@+id/take_bt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="onClick"
android:text="拍照" />

<Button
android:id="@+id/cancel_bt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="onClick"
android:text="取消" />

<Button
android:id="@+id/save_bt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="onClick"
android:text="保存" />

<Button
android:id="@+id/change_bt"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="onClick"
android:text="切换" />

</LinearLayout>
</LinearLayout>