调用相机拍照，并获取显示图片

1. 请求使用相机，判断是否需要申请权限。

public void takePhoto(View view){
    if (Build.VERSION.SDK_INT>=Build.VERSION_CODES.M){
        if (ContextCompat.checkSelfPermission(this,
                Manifest.permission.CAMERA)!= PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(this,new String[]{
                    Manifest.permission.WRITE_EXTERNAL_STORAGE
                    ,Manifest.permission.READ_EXTERNAL_STORAGE,
                            Manifest.permission.CAMERA}, 123);
        }
    }else {
          Intent intent=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

          Uri uri=Uri.fromFile(new File(path)); // path自己定义的图片位置
          intent.putExtra(MediaStore.EXTRA_OUTPUT,uri); //配置图片存储位置 不需要可以忽略
          startActivityForResult(intent,1818);
    }
}

2. 申请权限返回结果处理

@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
    super.onRequestPermissionsResult(requestCode, permissions, grantResults);
    if (requestCode==123) {
        boolean grantedAll=true;
        for (int rangtResult:grantResults) {
            if (rangtResult!=PackageManager.PERMISSION_GRANTED){
                grantedAll=false;
                break;
            }
        }
        if (grantedAll){

          Intent intent=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

          Uri uri=Uri.fromFile(new File(path)); // path自己定义的图片位置
          intent.putExtra(MediaStore.EXTRA_OUTPUT,uri); //配置图片存储位置 不需要可以忽略
          startActivityForResult(intent,1818);

        }
    }
}

3. 接收图片并处理

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode== Activity.RESULT_OK){
        if (requestCode==1818){
            //这里可以对图片裁剪、压缩等处理，如获取图库图片一样，我这就直接显示了
            iv2.setImageURI(Uri.fromFile(new File(path)));
        }
    }
}