小编Jua*_*tel的帖子

我有一个类,有一个方法试图从清单中检索元数据.一切正常,除了我从应用程序信息创建的包返回空值

这是代码:

    private int getCurrentVersion(){
    int currVersion = 0;

    try {
        ApplicationInfo app = context.getPackageManager().getApplicationInfo(context.getPackageName(),PackageManager.GET_META_DATA);
        Bundle bundle = app.metaData;

        for (String key: bundle.keySet())
        {
          Log.d ("TEST", key + " is a key in the bundle");
        }

        Log.d("TEST","google: "+bundle.getString("com.google.android.gms.version"));
        Log.d("TEST","version: "+bundle.getString("dbVersion"));

        //currVersion = Integer.valueOf(bundle.getString("dbVersion"));
        currVersion = 1;
    } catch (NameNotFoundException e) {
        e.printStackTrace();
    } catch (NullPointerException e) {
        e.printStackTrace();         
    }

    return currVersion;
}


03-05 18:53:23.818: D/TEST(31400): com.google.android.gms.version is a key in the bundle
03-05 18:53:23.818: D/TEST(31400): dbVersion is a key in …

这是我第一次使用相机.我已经阅读了很多例子和文档,所以我试着让自己的班级用前置摄像头拍照.

这就是我想出的:

    public class CameraController {

private Context context;

private boolean hasCamera;

private Camera camera;
private int cameraId;

public CameraController(Context c){
    context = c.getApplicationContext();

    if(context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA)){
        cameraId = getFrontCameraId();

        if(cameraId != -1){
            hasCamera = true;
        }else{
            hasCamera = false;
        }
    }else{
        hasCamera = false;
    }
}

public boolean hasCamera(){
    return hasCamera;
}

public void getCameraInstance(){
    camera = null;

    if(hasCamera){
        try{
            camera = Camera.open(cameraId);
        }
        catch(Exception e){

        }
    }
}

public void takePicture(){
    if(hasCamera){
        camera.takePicture(null,null,mPicture);
    }
}

public void releaseCamera(){
    if(camera != …