Android-相机与相册

打开相机：

//Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
//打开相机方式一
//Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
//打开相机方式二
File file=new File(Environment.getExternalStorageDirectory(), "camera.jpg");
//创建图片路径和名称
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(file));//图片输出位置
intent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 0);/*图片质量，范围[0,1]*/
startActivityForResult(intent, 10);

打开相册：

    Intent intent = new Intent(Intent.ACTION_GET_CONTENT);              
    intent.addCategory(Intent.CATEGORY_OPENABLE);
    intent.setType("image/*");
    intent.putExtra("crop", "true");
    intent.putExtra("aspectX", 1);
    intent.putExtra("aspectY", 1);
    intent.putExtra("outputX", 80);
    intent.putExtra("outputY", 80);
    intent.putExtra("return-data", true);
    startActivityForResult(intent, 11);

打开录像：

//调用录像机功能的代码如下:
Intent intent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);
//限制质量
intent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 0.9);
//限制时长
intent.putExtra(MediaStore.EXTRA_DURATION_LIMIT, 5);
//限制大小
intent.putExtra(MediaStore.EXTRA_SIZE_LIMIT, 1024*1024);
startActivityForResult(intent, 11);

示例一：

activity_main1.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=".TakePhoto">

    <LinearLayout
        android:id="@+id/layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <Button
            android:id="@+id/btn_1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="takePhotos"
            android:text="不指定路径拍照：缩略图" />

        <Button
            android:id="@+id/btn_2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="takePhotos"
            android:text="指定路径拍照：原图" />

        <Button
            android:id="@+id/btn_3"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="takePhotos"
            android:text="常用方法拍照：数据库更新" />
    LinearLayout>

    <ImageView
        android:id="@+id/iv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/layout"
        android:layout_centerInParent="true"
        android:scaleType="fitXY" />
RelativeLayout>

TakePhoto.java

package com.example.administrator.myangularjsweb;

import android.content.ContentValues;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.ImageView;

import java.io.File;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * Created by Administrator on 2017/3/14.
 */

public class TakePhoto extends AppCompatActivity {

    private ImageView iv;
    private Bitmap bitmap;
    private Uri uri;
    private SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main1);

        iv = ((ImageView) findViewById(R.id.iv));
    }

    public void takePhotos(View view) {
        Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

        switch (view.getId()) {
            case R.id.btn_1://没有路径：缩略图
                startActivityForResult(intent, 1);
                break;

            case R.id.btn_2://原图
                //获取系统下载目录，外部存储download文件夹下
                File dir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
                //设置图片名称
                String name = "IMG" + sdf.format(new Date()) + ".png";
                uri = Uri.fromFile(new File(dir, name));
                //设置拍摄照片的保存路径
                intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
                startActivityForResult(intent, 2);
                break;

            case R.id.btn_3://最常用方式
                ContentValues contentValues = new ContentValues();
                //设置拍摄照片的名称
                contentValues.put(MediaStore.Images.Media.DISPLAY_NAME, "IMG" + sdf.format(new Date()) + ".png");
                //向保存照片的数据库插入一条数据
                Uri uri1 = getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, contentValues);
                intent.putExtra(MediaStore.EXTRA_OUTPUT, uri1);
                startActivityForResult(intent, 3);
                break;
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == 1 && resultCode == RESULT_OK) {
            bitmap = ((Bitmap) data.getExtras().get("data"));
            Log.d("google_lenve_fb", "onActivityResult: width:" + bitmap.getWidth() + ";height:" + bitmap.getHeight());
            iv.setImageBitmap(bitmap);
        } else if (requestCode == 2 && resultCode == RESULT_OK) {
            iv.setImageURI(uri);
        } else if (requestCode == 3 && resultCode == RESULT_OK) {
            //从Images的ContentProvider中查询数据
            //1.要查询数据的URI
            //2.要查询的字段
            //3.查询条件
            //4.查询条件中占位符的值
            //5.排序字段
            Cursor cursor = getContentResolver().query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, new
                    String[]{MediaStore.Images
                    .Media.DATA}, null, null, MediaStore.Images.Media.DATE_ADDED + " Desc");//Desc前有一个空格

            //第一条数据就是刚刚拍摄的照片的信息
            if (cursor.moveToFirst()) {
                //获得图片存储路径（不同手机会有差异）
                String imagePath = cursor.getString(0);
//                String path = mCursor.getString(_date);

                Log.d("google_lenve_fb", "onActivityResult: imagePath:" + imagePath);
                Bitmap bitmap = BitmapFactory.decodeFile(imagePath);
                iv.setImageBitmap(bitmap);
                cursor.close();
            }
        }
    }
}

示例二：

activity_camera_show.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

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

    <Button
        android:id="@+id/button_photoButton"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="相册" />

    <ImageView
        android:id="@+id/imageview_preview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_gravity="center"
        android:src="@mipmap/ic_launcher" />


LinearLayout>

TakePhoto2.java

依赖：

compile 'com.squareup.picasso:picasso:2.5.2'

package com.example.administrator.myangularjsweb;

import android.app.Activity;
import android.content.ContentResolver;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;

import com.squareup.picasso.Picasso;

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

/**
 * Created by Administrator on 2017/3/14.
 */

public class TakePhoto2 extends AppCompatActivity {

    private static final String TAG = "TakePhoto2";
    private ImageView mImageView;
    private Button mButtonCamera;
    private Button mButtonPhoto;

    private static final int REQUEST_CAMERA = 111;
    private static final int REQUEST_ALBUM_OK = 222;

    File mTmpFile;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_camera_show);
        mImageView = (ImageView) this.findViewById(R.id.imageview_preview);
        mButtonCamera = (Button) this.findViewById(R.id.button_cameraButton);
        mButtonPhoto = (Button) this.findViewById(R.id.button_photoButton);

        //打开Camera
        mButtonCamera.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                // 跳转到系统照相机,隐示意图：指定action，不指定activity
                Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

                //对隐式Intent的运行时检查保护，防止系统相机应用被关闭或者不存在相机应用而crash
                if (cameraIntent.resolveActivity(getPackageManager()) != null) {
                    // 设置系统相机拍照后的输出路径
                    // 创建临时文件，使用系统上下文避免内存泄漏
                    mTmpFile = OtherUtils.createFile(getApplicationContext());

                    /*输出文件路径和文件名=name:output,value:URI*/
                    cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(mTmpFile));
                    startActivityForResult(cameraIntent, REQUEST_CAMERA);
                } else {
                    Toast.makeText(getApplicationContext(), "你的手机竟然没相机！！！！", Toast.LENGTH_SHORT).show();
                }
            }
        });

        //获取相册
        mButtonPhoto.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent albumIntent = new Intent(Intent.ACTION_PICK, null);
                albumIntent.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, "image/*");
                startActivityForResult(albumIntent, REQUEST_ALBUM_OK);
            }
        });

    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        switch (requestCode) {
            case REQUEST_CAMERA://打开相机拍照后
                if (mTmpFile != null) {
                    Log.d(TAG, "onActivityResult: 请求相机： " + mTmpFile.getAbsolutePath());
                    //打印结果：/storage/emulated/0/1489474548266.jpg

                    Picasso.with(this)
                            .load(mTmpFile)
                            .centerCrop()
                            .resize(OtherUtils.dip2px(this, 100), OtherUtils.dip2px(this, 100))
                            .error(R.mipmap.ic_launcher)
                            .into(mImageView);
                }
                break;
            case REQUEST_ALBUM_OK://打开相册选取图片后
                Log.d(TAG, "onActivityResult:相册 " + data.getData().toString());
                //打印结果：file:///storage/emulated/0/DCIM/Camera/IMG_20170102_115337_HDR.jpg

                // 外界的程序通过ContentResolver接口可以访问ContentProvider提供的数据，
                // 在Activity当中通过getContentResolver()可以得到当前应用的 ContentResolver实例
                ContentResolver resolver = getContentResolver();

                try {
                    InputStream inputStream = resolver.openInputStream(data.getData());/*获取输入流*/

                    Bitmap bitmap = BitmapFactory.decodeStream(inputStream);/*流操作*/

                    mImageView.setImageBitmap(bitmap);

                    inputStream.close();/*关闭流*/
                } catch (FileNotFoundException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                break;

        }
    }


}

OtherUtils.java

package com.example.administrator.myangularjsweb;

import android.content.Context;
import android.os.Environment;

import java.io.File;
import java.util.Date;

/**
 * Created by Administrator on 2017/3/14.
 */

public class OtherUtils {
    public static int dip2px(Context context, float dpValue) {
        final float scale = context.getResources().getDisplayMetrics().density;
        return (int) (dpValue * scale + 0.5f);
    }

    public static int px2dip(Context context, float pxValue) {
        final float scale = context.getResources().getDisplayMetrics().density;
        return (int) (pxValue / scale + 0.5f);
    }

    /**
     * 获取拍照相片存储文件
     *
     * @param context
     * @return
     */
    public static File createFile(Context context) {
        File file;
        if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
            String timeStamp = String.valueOf(new Date().getTime());
            file = new File(Environment.getExternalStorageDirectory() +
                    File.separator + timeStamp + ".jpg");
        } else {
            File cacheDir = context.getCacheDir();
            String timeStamp = String.valueOf(new Date().getTime());
            file = new File(cacheDir, timeStamp + ".jpg");
        }
        return file;
    }

}

对于某个已知的uri，获取二进制文件读写

//      对于某个已知的uri，获取二进制文件读写
        try{
            OutputStream file = getContentResolver().openOutputStream(uri);
//            ... ... //写处理
            file.close();
        }catch (Exception e){
            Log.e(TAG,e.toString());
        }

        try{
            InputStream in = getContentResolver().openInputStream(uri);
//            ... ... //读处理
            in.close();
        }catch (Exception e){
            Log.e(TAG,e.toString());
        }

参考：

Android Camera 使用小结
Android - 使用Intent来启动Activity
android 多媒体和相机详解五
getContentResolver
Pro Android学习笔记（九）：了解Content Provider（下下）

Intent之resolveActivity（） 防止APP崩溃
resolveActivity—-对隐式Intent的运行时检查保护

resolveActivity API的使用范例如下：

Intent intent = new Intent(Intent.ACTION_XXX);
ComponentName componentName = intent.resolveActivity(getPackageManager());
if(componentName != null) {
    String className = componentName.getClassName();
}

通过PackageManager可以判断Android设备是否有相机！

PackageManager pm = getPackageManager();  
// FEATURE_CAMERA - 后置相机  
// FEATURE_CAMERA_FRONT - 前置相机  
if (!pm.hasSystemFeature(PackageManager.FEATURE_CAMERA)  
        && !pm.hasSystemFeature(PackageManager.FEATURE_CAMERA_FRONT)) {  
    Log.i("camera", "non-support");  
} else {  
    Log.i("camera", "support");  
}