Android拍照，相冊選擇圖片以及Android6.0權限管理

ActivityCompat.requestPermissions(this,
                    new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                    MY_PERMISSIONS_REQUEST_CALL_PHONE2);

第二個參數是一個字符串數組，裡面是你需要申請的權限。既然是一個數組，那麼就說明你一次可以申請多個權限。由於拍照和選擇相冊圖片只涉及一個權限，所以上面的字符串數組中就只寫了一個權限。最後一個參數是一個整型常量，用於標志你這次申請的權限，該常量在onRequestPermissionsResult(…)方法中會用到。

判斷用戶是否授予該權限

   @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults)
    {

        if (requestCode == MY_PERMISSIONS_REQUEST_CALL_PHONE)
        {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED)
            {
               takePhoto();
            } else
            {
                // Permission Denied
                Toast.makeText(MainActivity.this, "Permission Denied", Toast.LENGTH_SHORT).show();
            }
        }


        if (requestCode == MY_PERMISSIONS_REQUEST_CALL_PHONE2)
        {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED)
            {
                choosePhoto();
            } else
            {
                // Permission Denied
                Toast.makeText(MainActivity.this, "Permission Denied", Toast.LENGTH_SHORT).show();
            }
        }
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    }

如果用戶同意，那麼就執行相應的方法，如果拒絕，可以向用戶解釋一下申請該權限的原因。

4，代碼

public class MainActivity extends AppCompatActivity {
    private ImageView imageView;
    private static final int CROP_PHOTO = 2;
    private static final int REQUEST_CODE_PICK_IMAGE=3;
    private static final int MY_PERMISSIONS_REQUEST_CALL_PHONE = 6;
    private static final int MY_PERMISSIONS_REQUEST_CALL_PHONE2 = 7;
    private  File output;
    private Uri imageUri;

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

    void initView(){
        imageView=(ImageView)findViewById(R.id.image);
    }

    public void takePhone(View view){
        if (ContextCompat.checkSelfPermission(this,
                Manifest.permission.WRITE_EXTERNAL_STORAGE)
                != PackageManager.PERMISSION_GRANTED)
        {
            ActivityCompat.requestPermissions(this,
                    new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                    MY_PERMISSIONS_REQUEST_CALL_PHONE2);

        }else {
            takePhoto();
        }

    }

    public void choosePhone(View view){
        if (ContextCompat.checkSelfPermission(this,
                Manifest.permission.WRITE_EXTERNAL_STORAGE)
                != PackageManager.PERMISSION_GRANTED)
        {
            ActivityCompat.requestPermissions(this,
                    new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                    MY_PERMISSIONS_REQUEST_CALL_PHONE2);

        }else {
            choosePhoto();
        }
    }

    /**
     * 拍照
     */
    void takePhoto(){
        /**
         * 最後一個參數是文件夾的名稱，可以隨便起
         */
        File file=new File(Environment.getExternalStorageDirectory(),"拍照");
        if(!file.exists()){
            file.mkdir();
        }
        /**
         * 這裡將時間作為不同照片的名稱
         */
        output=new File(file,System.currentTimeMillis()+".jpg");

        /**
         * 如果該文件夾已經存在，則刪除它，否則創建一個
         */
        try {
            if (output.exists()) {
                output.delete();
            }
            output.createNewFile();
        } catch (Exception e) {
            e.printStackTrace();
        }
        /**
         * 隱式打開拍照的Activity，並且傳入CROP_PHOTO常量作為拍照結束後回調的標志
         */
        imageUri = Uri.fromFile(output);
        Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
        intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
        startActivityForResult(intent, CROP_PHOTO);

    }

    /**
     * 從相冊選取圖片
     */
    void choosePhoto(){
        /**
         * 打開選擇圖片的界面
         */
        Intent intent = new Intent(Intent.ACTION_PICK);
        intent.setType("image/*");//相片類型
        startActivityForResult(intent, REQUEST_CODE_PICK_IMAGE);

    }

    public void onActivityResult(int req, int res, Intent data) {
        switch (req) {
            /**
             * 拍照的請求標志
             */
            case CROP_PHOTO:
                if (res==RESULT_OK) {
                    try {
                        /**
                         * 該uri就是照片文件夾對應的uri
                         */
                        Bitmap bit = BitmapFactory.decodeStream(getContentResolver().openInputStream(imageUri));
                        imageView.setImageBitmap(bit);
                    } catch (Exception e) {
                        Toast.makeText(this,"程序崩潰",Toast.LENGTH_SHORT).show();
                    }
                }
                else{
                    Log.i("tag", "失敗");
                }

                break;
            /**
             * 從相冊中選取圖片的請求標志
             */

            case REQUEST_CODE_PICK_IMAGE:
                if (res == RESULT_OK) {
                    try {
                        /**
                         * 該uri是上一個Activity返回的
                         */
                        Uri uri = data.getData();
                        Bitmap bit = BitmapFactory.decodeStream(getContentResolver().openInputStream(uri));
                        imageView.setImageBitmap(bit);
                    } catch (Exception e) {
                        e.printStackTrace();
                        Log.d("tag",e.getMessage());
                        Toast.makeText(this,"程序崩潰",Toast.LENGTH_SHORT).show();
                    }
                }
                else{
                    Log.i("liang", "失敗");
                }

                break;

            default:
                break;
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults)
    {

        if (requestCode == MY_PERMISSIONS_REQUEST_CALL_PHONE)
        {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED)
            {
               takePhoto();
            } else
            {
                // Permission Denied
                Toast.makeText(MainActivity.this, "Permission Denied", Toast.LENGTH_SHORT).show();
            }
        }


        if (requestCode == MY_PERMISSIONS_REQUEST_CALL_PHONE2)
        {
            if (grantResults[0] == PackageManager.PERMISSION_GRANTED)
            {
                choosePhoto();
            } else
            {
                // Permission Denied
                Toast.makeText(MainActivity.this, "Permission Denied", Toast.LENGTH_SHORT).show();
            }
        }
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    }
}