android实现拍照功能

Android中实现拍照有两种方法，一种是调用系统自带的相机，然后使用其返回的照片数据。还有一种是自己用Camera类和其他相关类实现相机功能，这种方法定制度比较高，洗染也比较复杂，一般平常的应用只需使用第一种即可。

用Intent启动相机的代码：

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);startActivityForResult(intent, 1);

要将图像存储到SD卡上之前，最好检查一下SD卡是否可用

String sdStatus = Environment.getExternalStorageState();            if (!sdStatus.equals(Environment.MEDIA_MOUNTED)) { // 检测sd是否可用                Log.v("TestFile",                        "SD card is not avaiable/writeable right now.");                return;            }

另外，要注意的是读写SD卡必须在Mainifest.xml文件中配置权限：

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

一个示例如下：

MainActivity.java:

package com.example.testand;import java.io.File;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import android.os.Bundle;import android.os.Environment;import android.provider.MediaStore;import android.app.Activity;import android.content.Intent;import android.graphics.Bitmap;import android.util.Log;import android.view.Menu;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.ImageView;public class MainActivity extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);Button button=(Button) findViewById(R.id.button);button.setOnClickListener(new OnClickListener(){@Overridepublic void onClick(View v) {Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);startActivityForResult(intent, 1);}});}protected void onActivityResult(int requestCode, int resultCode, Intent data){super.onActivityResult(requestCode, resultCode, data);String sdStatus = Environment.getExternalStorageState();        if (!sdStatus.equals(Environment.MEDIA_MOUNTED)) { // 检测sd是否可用            Log.v("TestFile","SD card is not avaiable/writeable right now.");            return;        }        Bundle bundle = data.getExtras();        Bitmap bitmap = (Bitmap) bundle.get("data");// 获取相机返回的数据，并转换为Bitmap图片格式        File file = new File("/sdcard/myImage/");        FileOutputStream bout = null;                file.mkdirs();// 创建文件夹        String fileName = "/sdcard/myImage/111.jpg";        try {        bout = new FileOutputStream(fileName);            bitmap.compress(Bitmap.CompressFormat.JPEG, 100, bout);// 把数据写入文件        } catch (FileNotFoundException e) {            e.printStackTrace();        } finally {            try {            bout.flush();            bout.close();            } catch (IOException e) {                e.printStackTrace();            }        }        ((ImageView) findViewById(R.id.imageView)).setImageBitmap(bitmap);// 将图片显示在ImageView里}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.main, menu);return true;}}

activity_main.xml:

<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:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context=".MainActivity" >       <Button        android:id="@+id/button"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="点击启动相机" />    <ImageView        android:id="@+id/imageView"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:layout_alignLeft="@+id/button"        android:layout_alignParentBottom="true"        android:layout_below="@+id/button"        android:background="#999999" />    </RelativeLayout>

AndroidManifest.xml:

<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.example.testand"    android:versionCode="1"    android:versionName="1.0" >    <uses-sdk        android:minSdkVersion="8"        android:targetSdkVersion="17" />    <application        android:allowBackup="true"        android:icon="@drawable/ic_launcher"        android:label="@string/app_name"        android:theme="@style/AppTheme" >        <activity            android:name="com.example.testand.MainActivity"            android:label="@string/app_name" >            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>            </application>        <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />        <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" /></manifest>

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