调用摄像头和相册

MainActivity.java

import android.Manifest;
import android.content.ContentUris;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.provider.DocumentsContract;
import android.provider.MediaStore;
import android.support.annotation.RequiresApi;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v4.content.FileProvider;
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 java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;

import csdn.example.com.notification.R;

public class Main2Activity extends AppCompatActivity {

    public static  final  int TAKEPHOTO = 1;
    public static final  int CHOOSE_PHOTO = 2;
    private ImageView picture;
    private Uri imageUri;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        //拍照片按钮
        Button takePhoto = (Button) findViewById(R.id.take_photo);
        //从相册中选照片按钮
        Button ChooseFromAlbum = (Button) findViewById(R.id.choose_from_album);


        picture = (ImageView) findViewById(R.id.picture);
        takePhoto.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                //创建File对象，用于存储拍照后的照片
                File outputImage = new File(getExternalCacheDir(),
                        "output_image.jpg");
                try {
                    if(outputImage.exists()){
                        outputImage.delete();
                    }
                    outputImage.createNewFile();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if(Build.VERSION.SDK_INT >= 24){
                    imageUri = FileProvider.getUriForFile(Main2Activity.this,
                            "csdn.example.com.notification.CameraAlbumTest",outputImage);
                }else {
                    imageUri = Uri.fromFile(outputImage);
                }
                //启动相机程序
                Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
                intent.putExtra(MediaStore.EXTRA_OUTPUT,imageUri);
                startActivityForResult(intent,TAKEPHOTO);
            }
        });
        ChooseFromAlbum.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(ContextCompat.checkSelfPermission(Main2Activity.this,
                        Manifest.permission.WRITE_EXTERNAL_STORAGE)!= PackageManager.PERMISSION_GRANTED){

                    ActivityCompat.requestPermissions(Main2Activity.this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},1);
                }else {
                    openAlbum();
                }
            }
        });
    }

    /**
     * 功能：打开相册
     */
    private void openAlbum() {
        //动态申请write_external_storage这个危险权限
        Intent intent = new Intent("android.intent.action.GET_CONTENT");
        intent.setType("image/*");
        startActivityForResult(intent,CHOOSE_PHOTO); //打开相机
        Log.d("Picture","1");
    }


    @Override
    public void onRequestPermissionsResult(int requestCode,  String[] permissions,  int[] grantResults) {
        switch (requestCode){
            case 1:
                if(grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED){
                    openAlbum();
                }else {
                    Toast.makeText(this,"你否认了许可",Toast.LENGTH_SHORT).show();
                }
                break;
            default:
        }

    }

    /**
     * 对封装过的Uri进行解析
     * @param data
     */
    @RequiresApi(api = Build.VERSION_CODES.KITKAT)
    private void handlerImageOnKitKat(Intent data) {
        Log.d("Picture","2");
        String imagePath = null;
        Uri uri = data.getData();
        if(DocumentsContract.isDocumentUri(this,uri)){
            //如果是document类型的Uri,则通过document id 处理
            String docId = DocumentsContract.getDocumentId(uri);
            //如果Uri的authority是media格式的话，还需要进一步解析
            if("com.android.providers.media.documents".equals(uri.getAuthority())){
                //通过字符串分割取出后半部分才能得到真正的数字
                String id = docId.split(":")[1]; //解析出数字格式的id
                //重新构建和条件语句
                String selection = MediaStore.Images.Media._ID + "=" + id;
                imagePath = getImagePath(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,selection);
            }else if("com.android.providers.downloads.documents".equals(uri.getAuthority())){
                Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://download.public_downloads"),Long.valueOf(docId));
                imagePath = getImagePath(contentUri,null);
            }
        }else if("content".equalsIgnoreCase(uri.getScheme())){
            //如果是content类型的Uri ,则使用普通方式处理
            imagePath = getImagePath(uri,null);
        }else  if("file".equalsIgnoreCase(uri.getScheme())){
            //如果是file类型的Uri，直接获取图片路径即可
            imagePath = uri.getPath();

        }
        dispalyImage(imagePath); //根据图片路径显示图片
    }

    private  void handleImageBeforeKitkat(Intent data){
        Log.d("Picture","3");
        Uri uri = data.getData();
        String imagePath = getImagePath(uri,null);
        dispalyImage(imagePath);
    }

    /**
     * 获得图片真实路径
     * @param uri
     * @param selection
     * @return
     */
    private String getImagePath(Uri uri, String selection) {
        Log.d("Picture","得到照片");
        String path = null;
        //通过Uri 和 selection获得真实的图片路径
        Cursor cursor = getContentResolver().query(uri,null,selection,null,null);
        if(cursor != null){
            if(cursor.moveToFirst()){
                path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));
            }
            cursor.close();
        }
        return path;
    }


    /**
     * 函数名称：dispalyImage
     * 返回值类型：无参
     * 传入的参数：imagePath
     * 传出的参数：无
     * 功能：将图片显示到街面上
     * @param imagePath
     */
    private void dispalyImage(String imagePath) {
        Log.d("Picture","拿到照片了吗？"+imagePath);
        if(imagePath != null){
            Log.d("Picture","拿到照片了吗？");
            Toast.makeText(this,"你成功的打开了图片",Toast.LENGTH_SHORT).show();
            Bitmap bitmap = BitmapFactory.decodeFile(imagePath);
            picture.setImageBitmap(bitmap);
            Log.d("Picture","拿到照片了ba？");

        }else {
            Toast.makeText(this,"failed to get image",Toast.LENGTH_SHORT).show();
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        switch (requestCode){

            case TAKEPHOTO:
                if(resultCode == RESULT_OK){
                    Log.d("Picture","到这里了没有1111？");
                    try {
                        //将拍摄照片显示出来
                        Bitmap bitmap = BitmapFactory.decodeStream(getContentResolver().openInputStream(imageUri));
                        picture.setImageBitmap(bitmap);
                    } catch (FileNotFoundException e) {
                        e.printStackTrace();
                    }
                }
                break;
            case CHOOSE_PHOTO:
                Log.d("Picture","到这里了没有？");
                if(resultCode == RESULT_OK){
                    Log.d("Picture","？？？2222");
                    //判断手机系统版本
                    if(Build.VERSION.SDK_INT >= 19){
                        //4.4及以上系统使用这个方法处理图片
                        handlerImageOnKitKat(data);
                    }else {
                        //4.4以下系统使用这个方法处理图片
                        handleImageBeforeKitkat(data);
                    }
                }
                break;
            default:
                break;
        }
        super.onActivityResult(requestCode, resultCode, data);
    }






}

activity_main.xml

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

    <Button
        android:id="@+id/take_photo"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="拍照片" />

    <ImageView
        android:id="@+id/picture"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal" />
    <Button
        android:id="@+id/choose_from_album"
        android:text="从相册里打开照片"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />
</LinearLayout>

运行图片如下

拍照

从相册选择照片

清单文件

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="csdn.example.com.notification">

    <uses-permission android:name="android.permission.VIBRATE" />
    <uses-permission android:name="android.permission.BIND_NOTIFICATION_LISTENER_SERVICE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <provider
            android:authorities="csdn.example.com.notification.CameraAlbumTest"
            android:name="android.support.v4.content.FileProvider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/file_paths"/>
        </provider>
        <activity android:name=".CameraAlbumTest.Main2Activity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>

</manifest>