利用摄像头摄像或拍照（二）

来源：互联网发布：手机怎么清理数据编辑：程序博客网时间：2024/05/16 17:25

需求：预览摄像头，并实现前后摄像头切换

实现：集成Surface，并通过Camera.open(0)和Camera.open(1)来启动后置和前置摄像头

代码如下：

ShowView.java类用来显示预览界面

package com.davidtao.camerashooting;import android.app.Activity;import android.content.Context;import android.content.Intent;import android.content.pm.ActivityInfo;import android.hardware.Camera;import android.hardware.Camera.CameraInfo;import android.os.Bundle;import android.util.Log;import android.view.View;import android.view.View.OnClickListener;import android.view.Window;import android.widget.FrameLayout;import android.widget.Toast;/** *  * @author DavidTao * */public class ShowView extends Activity implements OnClickListener{/** 相机*/private Camera mCamera;private Context mContext;private CameraView mCameraView;/** 当前相机信息*/private CameraInfo mCameraInfo;/** 放置预览界面*/private FrameLayout mFrameLayout;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);mContext = this;/** 没有标题栏*/requestWindowFeature(Window.FEATURE_NO_TITLE);/** 设置横屏*/setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);setContentView(R.layout.camera_view);if(initCamera()) {/** 厨师话相机预览界面*/mCameraView = new CameraView(mContext, mCamera);mFrameLayout = (FrameLayout) findViewById(R.id.camera);/** 加载界面*/mFrameLayout.addView(mCameraView);mFrameLayout.setOnClickListener(this);}}/** * 需要捕捉异常，当摄像头正在被占用的时候，会抛出异常 */private boolean initCamera() {try {mCameraInfo =new CameraInfo();/** 0默认为后置摄像头,获取后置摄像头的信息 */Camera.getCameraInfo(0, mCameraInfo);/** 开启后置摄像头*/mCamera = Camera.open(0);return true;} catch(Exception e) {e.printStackTrace();Toast.makeText(mContext, "摄像头正在被占用", Toast.LENGTH_LONG).show();Intent intent = new Intent(mContext, MainActivity.class);startActivity(intent);}return false;}@Overridepublic void onBackPressed() {mCamera.stopPreview();mCamera.release();mCamera = null;super.onBackPressed();}@Overridepublic void onClick(View v) {if (v.getId() == R.id.camera) {/** 停止预览*/mCamera.stopPreview();/** 释放资源*/mCamera.release();mCamera = null;if (mCameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_BACK) {/** 若原来是打开的后置摄像头，现在打开前置摄像头*/mCamera = Camera.open(1);/** 获取前置摄像头的信息*/Camera.getCameraInfo(1, mCameraInfo);} else {/** 若原来是打开的前置摄像头，现在打开后置摄像头*/mCamera = Camera.open(0);/** 获取后置摄像头的信息*/Camera.getCameraInfo(0, mCameraInfo);}mCameraView = new CameraView(mContext, mCamera);/** 删除原有View*/mFrameLayout.removeAllViews();/** 重新加载新的View*/mFrameLayout.addView(mCameraView);}}}

CameraView.java用来初始化预览界面VIew：

package com.davidtao.camerashooting;import java.io.IOException;import android.content.Context;import android.hardware.Camera;import android.view.SurfaceHolder;import android.view.SurfaceView;/** * 预览界面初始化 * @author DavidTao * */public class CameraView extends SurfaceView implements SurfaceHolder.Callback{private SurfaceHolder mSurfaceHolder;private Camera mCamera;public CameraView(Context context, Camera camera) {super(context);mCamera = camera;mSurfaceHolder = getHolder();mSurfaceHolder.addCallback(this);/** 若版本低于3.0,,还需要设置type*/mSurfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);}@Overridepublic void surfaceChanged(SurfaceHolder holder, int format, int width,int height) {// TODO Auto-generated method stub}/** * 创建surface，将holder的对象传给Camera */@Overridepublic void surfaceCreated(SurfaceHolder holder) {// TODO Auto-generated method stubtry {mCamera.setPreviewDisplay(mSurfaceHolder);mCamera.startPreview();} catch (IOException e) {e.printStackTrace();}}@Overridepublic void surfaceDestroyed(SurfaceHolder holder) {}}

布局文件：

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

需要权限：

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

这样，就可以实现前后摄像头的预览和切换。

（三）将会实现前后摄像头的拍照！

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