Question

我正在尝试在相机预览中使用微调器构建相机应用程序。我遗漏了一些我认为不可取的相机代码。当我按下它时，旋转器正在反应（改变颜色），但不会下降。我的微调器非常小（50dp），没有显示箭头，我的手机很旧但状况良好（Samsung Galaxy Pocket plus S5301，Android 4.04版）。也许这与表面变化有关？

爪哇：

public class CameraActivity extends AppCompatActivity implements SurfaceHolder.Callback {

private Camera camera;
private SurfaceView surfaceView;
private SurfaceHolder surfaceHolder;

Camera.PictureCallback rawCallback;
Camera.ShutterCallback shutterCallback;
Camera.PictureCallback jpegCallback;

private LayoutInflater controlInflater = null;
private final String TAG = "   CameraActivity";

static final int REQUEST_IMAGE_CAPTURE = 1;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_camera);
    setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_USER);
    getWindow().setFormat(PixelFormat.UNKNOWN);
    surfaceView = (SurfaceView)findViewById(R.id.camera_preview);
    surfaceHolder = surfaceView.getHolder();
    surfaceHolder.addCallback(this);
    surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    controlInflater = LayoutInflater.from(getBaseContext());
    View viewControl = controlInflater.inflate(R.layout.activity_camera, null);
    LayoutParams layoutParamsControl = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
    this.addContentView(viewControl, layoutParamsControl);
    if(!getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)) {
        Toast.makeText(getApplicationContext(), "Your phone does not have a camera.", Toast.LENGTH_SHORT).show();
        finish();
    }

    Spinner spinner1 = (Spinner) findViewById(R.id.spinner1);
    ArrayAdapter<CharSequence> adapter1 = ArrayAdapter.createFromResource(this, R.array.planets_array, android.R.layout.simple_spinner_item);
    adapter1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
    spinner1.setAdapter(adapter1);
}

public void refreshCamera() {
    if (surfaceHolder.getSurface() == null) {
        return;
    }

    try {
        camera.stopPreview();
    } catch (Exception e) {
        e.printStackTrace();
    }

    try {
        camera.setPreviewDisplay(surfaceHolder);
        camera.startPreview();
    } catch (Exception e) {
        e.printStackTrace();
    }
}


@Override
public void surfaceCreated(SurfaceHolder holder) {

    try {
        camera = Camera.open();
    } catch (Exception e) {
        e.printStackTrace();
    }

    Camera.Parameters param;
    param = camera.getParameters();
    param.setPreviewSize(352, 288);
    camera.setParameters(param);

    try {
        camera.setPreviewDisplay(surfaceHolder);
        camera.startPreview();
    }

    catch (Exception e) {
        System.err.println(e);
        return;
    }
}

@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
    refreshCamera();
}

XML

<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="package.main.CameraActivity">


<SurfaceView android:id="@+id/camera_preview"
    android:layout_width="match_parent"
    android:layout_height="match_parent"></SurfaceView>

<RelativeLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content">

    <LinearLayout android:id="@+id/topLayout"
        android:layout_alignParentTop="true"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <Spinner
            android:id="@+id/spinner1"
            android:layout_width="50dp"
            android:layout_height="50dp"
            android:layout_margin="10dp"
            android:dropDownWidth="200dp"
            android:paddingRight="14dp"
            android:background="@android:drawable/spinner_background"
            android:spinnerMode="dropdown" />

            //More spinners

     </LinearLayout>

           //Image in the middle of the screen

</RelativeLayout>
</FrameLayout>

XML values / strings.xml

 <resources>
<string-array name="planets_array">
    <item>Mercury</item>
    <item>Venus</item>
    <item>Earth</item>
    <item>Mars</item>
    <item>Jupiter</item>
    <item>Saturn</item>
    <item>Uranus</item>
    <item>Neptune</item>
</string-array>
</resources>

Answer 1

将根布局FrameLayout更改为RelativeLayout。

根据文档，FrameLayout应该只有一个孩子。

    "FrameLayout is designed to block out an area on the screen to display a single item. 
    Generally, FrameLayout should be used to hold a single child view, 
    because it can be difficult to organize child views in a way that's 
    scalable to different screen sizes without the children overlapping each other. 
    You can, however,
    add multiple children to a FrameLayout and control their position within the FrameLayout 
    by assigning gravity to each child,
    using the android:layout_gravity attribute."

Answer 2

你正在横向使用微调器。

Spinners将垂直显示项目。

Current Spinners horizontally Aligned

从＆＃34; wrap_content＆＃34;更改LinearLayout的高度to＆＃34; match_parent＆＃34;垂直查看微调器的项目。

After making changes

SurfaceView上的Android Spinner没有下降

2 个答案: