调用摄像头和相册

左手的ㄟ右手 2022-06-12 23:08 286阅读 0赞

## 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![这里写图片描述][SouthEast]

## 拍照 ##

![这里写图片描述][SouthEast 1]

![这里写图片描述][SouthEast 2]

## 从相册选择照片 ##

![这里写图片描述][SouthEast 3]

![这里写图片描述][SouthEast 4]

## 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>

[SouthEast]: /images/20220613/5e532e44ef2d479295a9a352bc4ddbc0.png
[SouthEast 1]: /images/20220613/f564ef5961654dc39f68505c0592ce70.png
[SouthEast 2]: /images/20220613/ddbc4cc13cb84a718dd0f1910121d29b.png
[SouthEast 3]: /images/20220613/8b863b3ec985426fb4cb4ab491e7721b.png
[SouthEast 4]: /images/20220613/0f589c99c6b147688c03fb046d598e2f.png