检查有无相机的权限

检查有无相机的权限

    public void actionCheckPermission(View view)
    {
        String perms = Manifest.permission.CAMERA;
        Integer nRet = 0;
        nRet = ContextCompat.checkSelfPermission(this, perms);
        if (nRet == PERMISSION_GRANTED)
        {
            Toast.makeText(this, "有权限", Toast.LENGTH_LONG).show();
        }
        else if(nRet == PERMISSION_DENIED)
        {
            Toast.makeText(this, "没有权限", Toast.LENGTH_LONG).show();
        }
        else
        {
            Toast.makeText(this, "非法返回值", Toast.LENGTH_LONG).show();
        }
    }

手机权限设置：

设置->授权管理->应用权限管理->权限管理

动态申请相机权限：

    public void actionRequestPermission(View view)
    {
        if(Build.VERSION.SDK_INT >= 23)
        {
            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA},123);
        }
        else
        {}
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if(requestCode == 123)
        {
            if(grantResults[0] == PERMISSION_GRANTED)
            {
                Toast.makeText(this, "申请权限成功", Toast.LENGTH_LONG).show();
            }
            else if(grantResults[0] == PERMISSION_DENIED)
            {
                Toast.makeText(this, "申请权限失败", Toast.LENGTH_LONG).show();
            }
            else
            {

            }
        }
    }