Android手机拍照功能的实现

一、布局文件main.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

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

    <RelativeLayout
        android:id="@+id/buttonlayout"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:visibility="gone" >

        <Button
            android:id="@+id/takepicture"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:layout_alignParentRight="true"
            android:layout_marginRight="5dp"
            android:onClick="takepicture"
            android:text="@string/takepicture" />

        <Button
            android:id="@+id/autofocus"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignTop="@id/takepicture"
            android:layout_marginRight="20dp"
            android:layout_toLeftOf="@id/takepicture"
            android:onClick="takepicture"
            android:text="@string/autofocus" />
    </RelativeLayout>

</FrameLayout>

二、MainActivity.java

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

import android.app.Activity;
import android.hardware.Camera;
import android.hardware.Camera.PictureCallback;
import android.os.Bundle;
import android.os.Environment;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.view.WindowManager;

public class MainActivity extends Activity {
    private View layout;
    private Camera camera;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.main);

        layout = this.findViewById(R.id.buttonlayout);

        SurfaceView surfaceView = (SurfaceView) this
                .findViewById(R.id.surfaceView);
        surfaceView.getHolder()
                .setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        surfaceView.getHolder().setFixedSize(176, 144);
        surfaceView.getHolder().setKeepScreenOn(true);
        surfaceView.getHolder().addCallback(new SurfaceCallback());
    }

    public void takepicture(View v) {
        if (camera != null) {
            switch (v.getId()) {
            case R.id.takepicture:
                camera.takePicture(null, null, new MyPictureCallback());
                break;

            case R.id.autofocus:
                camera.autoFocus(null);
                break;
            }
        }
    }

    private final class MyPictureCallback implements PictureCallback {
        public void onPictureTaken(byte[] data, Camera camera) {
            try {
                File jpgFile = new File(
                        Environment.getExternalStorageDirectory(),
                        System.currentTimeMillis() + ".jpg");
                FileOutputStream outStream = new FileOutputStream(jpgFile);
                outStream.write(data);
                outStream.close();
                camera.startPreview();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }

    }

    private final class SurfaceCallback implements Callback {
        public void surfaceCreated(SurfaceHolder holder) {
            try {
                camera = Camera.open();// 打开摄像头
                Camera.Parameters parameters = camera.getParameters();
                // Log.i("MainActivity", parameters.flatten());
                parameters.setPreviewSize(800, 480);
                parameters.setPreviewFrameRate(5);
                parameters.setPictureSize(1024, 768);
                parameters.setJpegQuality(80);
                camera.setParameters(parameters);
                camera.setPreviewDisplay(holder);
                camera.startPreview();// 开始预览
            } catch (Exception e) {
                e.printStackTrace();
            }
        }

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

        public void surfaceDestroyed(SurfaceHolder holder) {
            if (camera != null) {
                camera.release();
                camera = null;
            }
        }

    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if (event.getAction() == MotionEvent.ACTION_DOWN) {
            layout.setVisibility(ViewGroup.VISIBLE);
            return true;
        }
        return super.onTouchEvent(event);
    }
}

三、添加权限

 <uses-permission android:name="android.permission.CAMERA" />
    <!-- 在SDCard中创建与删除文件权限 -->
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
    <!-- 往SDCard写入数据权限 -->
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

效果如下：