小编jrm*_*mgx的帖子

我尝试使用以下代码从iphone相机保存视频文件:

class Camera {

...

private func loadDeviceInput() {
    let devices = AVCaptureDevice.devices() as! [AVCaptureDevice]
    for device in devices {
        if device.hasMediaType(AVMediaTypeVideo) {
            if device.position == .Back {
                _deviceBack = device
                _inputBack  = try? AVCaptureDeviceInput(device: device)
            }
            else if device.position == .Front {
                _deviceFront = device
                _inputFront  = try? AVCaptureDeviceInput(device: device)
            }
        }
        else if device.hasMediaType(AVMediaTypeAudio) {
            _inputAudio = try? AVCaptureDeviceInput(device: device)
        }
    }
}

private func loadDeviceOutput() {
    _outputStill = AVCaptureStillImageOutput()
    _outputStill?.outputSettings = [AVVideoCodecKey: AVVideoCodecJPEG]
    if _session.canAddOutput(_outputStill) {
        _session.addOutput(_outputStill) …

我尝试在我的应用程序中（希望）定义良好的视图（XML）上显示 ImageView

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activityShowLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#73C310"
android:orientation="vertical"
tools:context=".ShowActivity" >

<ImageView
    android:id="@+id/mainImage"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_above="@+id/moodButton"
    android:layout_alignParentLeft="true"
    android:layout_alignParentRight="true"
    android:layout_alignParentTop="true"
    android:layout_margin="12dp"
    android:background="#000"
    android:src="@drawable/gs_04_pic" />

<!-- ... -->

然后在我的活动的 onCreate 方法中

    @Override
public void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);

    setContentView(R.layout.activity_show);

    /* ... blabla bla ... */

    ImageView imageView = (ImageView) findViewById(R.id.mainImage);

    Bitmap bitmap = BitmapFactory.decodeByteArray(cream.getMedia(), 0, cream.getMedia().length);
    Drawable draw = new BitmapDrawable(getResources(), bitmap);
    imageView.setImageDrawable(draw);
    imageView.invalidate();
}

Cream.getMedia() 返回一个有效的 byte[] （来自数据库），我可以记录给我：

07-18 17:41:16.812: I/app(9883): 字节[] 是: [B@414af0b0

但最后 imageView 是黑色的（上面没有图像）如果我不运行 …