基于Android TextureView与SurfaceTexture实现相机Camera拍照预览与保存照片

基于Android TextureView与SurfaceTexture实现相机Camera拍照预览与保存照片

写一个简单的例子，实现一个常见的开发功能：拍照功能。
技术路线：通过TextureView的通道获取SurfaceTexture作为相机的预览，然后通过Camera的take方法把相机抓取的byte字节数据转换为Bitmap，然后存放到手机的存储器上，至此，一个最简单的拍照功能完成。
注意，本例如果运行在Android高版本（6.0+，7.0+或更高），需要多写运行时权限申请代码。本例出于功能演示，不再冗余的写这部分代码。只给出最骨干的关键代码逻辑。

布局文件activity_main.xml：

<?xml version="1.0" encoding="utf-8"?><RelativeLayout 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:background="@android:color/holo_blue_light"    tools:context="zhangphil.view.MainActivity">    <zhangphil.view.MyTextureView        android:id="@+id/textureView"        android:layout_width="300dp"        android:layout_height="200dp"        android:layout_centerInParent="true" />    <Button        android:id="@+id/capture"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_alignParentBottom="true"        android:layout_centerHorizontal="true"        android:text="拍摄" /></RelativeLayout>

MyTextureView.java：

package zhangphil.view;import android.content.Context;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.SurfaceTexture;import android.hardware.Camera;import android.os.Environment;import android.util.AttributeSet;import android.util.Log;import android.view.TextureView;import java.io.BufferedOutputStream;import java.io.File;import java.io.FileOutputStream;/** * Created by Phil on 2017/9/13. */public class MyTextureView extends TextureView {    public Camera mCamera;    public MyTextureView(Context context, AttributeSet attrs) {        super(context, attrs);        init();    }    private void init() {        mCamera = Camera.open();        this.setSurfaceTextureListener(new SurfaceTextureListener() {            @Override            public void onSurfaceTextureAvailable(SurfaceTexture surfaceTexture, int width, int height) {                try {                    mCamera.setPreviewTexture(surfaceTexture);                    mCamera.startPreview();                } catch (Exception e) {                    e.printStackTrace();                }            }            @Override            public void onSurfaceTextureSizeChanged(SurfaceTexture surfaceTexture, int width, int height) {            }            @Override            public boolean onSurfaceTextureDestroyed(SurfaceTexture surfaceTexture) {                mCamera.stopPreview();                mCamera.release();                mCamera = null;                return true;            }            @Override            public void onSurfaceTextureUpdated(SurfaceTexture surfaceTexture) {            }        });    }    public void take() {        if(mCamera!=null)            mCamera.takePicture(null, null, mPictureCallback);    }    Camera.PictureCallback mPictureCallback = new Camera.PictureCallback() {        @Override        public void onPictureTaken(byte[] data, Camera camera) {            mCamera.stopPreview();            new FileSaver(data).save();        }    };    private class FileSaver implements Runnable {        private byte[] buffer;        public FileSaver(byte[] buffer) {            this.buffer = buffer;        }        public void save() {            new Thread(this).start();        }        @Override        public void run() {            try {                File file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM), "zhangphil.png");                file.createNewFile();                FileOutputStream os = new FileOutputStream(file);                BufferedOutputStream bos = new BufferedOutputStream(os);                Bitmap bitmap = BitmapFactory.decodeByteArray(buffer, 0, buffer.length);                bitmap.compress(Bitmap.CompressFormat.PNG, 100, bos);                bos.flush();                bos.close();                os.close();                Log.d("照片已保存", file.getAbsolutePath());                mCamera.startPreview();            } catch (Exception e) {                e.printStackTrace();            }        }    }}

MainActivity.java：

package zhangphil.view;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.view.View;public class MainActivity extends AppCompatActivity {    private MyTextureView textureView;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        textureView = (MyTextureView) findViewById(R.id.textureView);        findViewById(R.id.capture).setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View view) {                textureView.take();            }        });    }}

权限：

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

代码运行结果：