小编Lee*_*ong的帖子

我有下面的代码隐藏并显示导航栏.它在第一个视图加载时隐藏,然后在调用"children"时隐藏.麻烦的是,当他们回到根视图时,我找不到触发它再次隐藏的事件/动作....

我在根页面上有一个"测试"按钮,用于手动执行操作,但它并不漂亮,我希望它是自动的.

-(void)hideBar 
{
    self.navController.navigationBarHidden = YES;
}
-(void)showBar 
{       
    self.navController.navigationBarHidden = NO;
}

我有以下代码将旋转一个drawable一定程度的度.

    public Drawable rotateDrawable(float angle, Context context)
    {
      Bitmap arrowBitmap = BitmapFactory.decodeResource(context.getResources(), R.drawable.generic2rb);

      // Create blank bitmap of equal size
      Bitmap canvasBitmap = arrowBitmap.copy(Bitmap.Config.ARGB_8888, true);
      canvasBitmap.eraseColor(0x00000000);

      // Create canvas
      Canvas canvas = new Canvas(canvasBitmap);

      // Create rotation matrix
      Matrix rotateMatrix = new Matrix();
      rotateMatrix.setRotate(angle, canvas.getWidth()/2, canvas.getHeight()/2);

      //Draw bitmap onto canvas using matrix
      canvas.drawBitmap(arrowBitmap, rotateMatrix, null);

      return new BitmapDrawable(canvasBitmap); 
    }

新的SDK说明了

BitmapDrawable(canvasBitmap); 

已弃用.有什么选择吗？

http://developer.android.com/reference/android/graphics/drawable/BitmapDrawable.html

我有以下代码

class OverlayTask extends AsyncTask<Void, Void, Void> {
    @Override
    public void onPreExecute() {

        if (sites != null) {
            myMapView.getOverlays().remove(sites);
            myMapView.invalidate();
            sites = null;
        }
    }

    @Override
    public Void doInBackground(Void... unused) {
            grabShipsWithLocation();
            return (null);
    }

    @Override
    public void onPostExecute(Void unused) {
        myMapView.getOverlays().add(sites);
        myMapView.invalidate();
        isLoading = false;
    }
}

这似乎在一些测试设备上工作正常,但我发现在开发控制台上出现了很多错误.我似乎无法弄清楚为什么以及在哪里放置这个Looper.prepare().需要它吗？

java.lang.ExceptionInInitializerError
at com.test.appname.FinderMain$1.gotLocation(FinderMain.java:286)
at com.test.appname.MyLocation$GetLastLocation.run(MyLocation.java:89)
at java.util.Timer$TimerImpl.run(Timer.java:289)
Caused by: java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
at android.os.Handler.<init>(Handler.java:121)
at android.os.AsyncTask$InternalHandler.<init>(AsyncTask.java:421)
at android.os.AsyncTask$InternalHandler.<init>(AsyncTask.java:421)
at android.os.AsyncTask.<clinit>(AsyncTask.java:152)

按要求MyLocation.java

    class GetLastLocation …

我有以下代码在视图加载中添加一个观察者.

- (void)viewDidLoad
{
    [super viewDidLoad];

    [[NSNotificationCenter defaultCenter] addObserverForName:@"com.app.livedata.jsonupdated"
                                                      object:nil queue:[NSOperationQueue mainQueue] usingBlock:^(NSNotification *notif) {
                                                          NSLog(@"JSONUPDATED");
                                                      }];
}

这很好.但是当卸载视图并确认调用dealloc时,Notification仍在触发.

似乎没有一种方法可以停用这个观察者？

有可能stikethrough一个人UILabel吗？我似乎无法找到选项......

我一直在寻找免费或商业AR工具包,并需要一些最好的建议!

我不想拥有一个识别图案并创建形状的图案.我的想法使用本地位置并使用服务器中的POI将它们呈现到AR视图.

有任何想法吗？

这让我很沮丧!!!

它将在大多数时间被调用,但随后它会停止响应压力.它将在屏幕旋转和双击时调用.不要捏!

救命!

我有一个可以快速更新的注释数据集.目前我删除所有注释,然后将它们重新绘制回地图上.

NSArray *existingpoints = [mapView.annotations filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"!(self isKindOfClass: %@)", [MKUserLocation class]]];
[mapView removeAnnotations:existingpoints];

我在自定义对象中计算它们的位置,因此希望能够调用它并"移动"注释而不删除并将其重新添加回地图.我制作的示例调用工作,我想几乎"民意调查"在下面.

- (CLLocationCoordinate2D) coordinate
{
    CLLocationCoordinate2D coord;
    coord.latitude = [lat doubleValue];
    coord.longitude = [lon doubleValue];


        double differencetime = exampleTime;
        double speedmoving;
        double distanceTravelled = speedmoving * differencetime;

        CLLocationDistance movedDistance = distanceTravelled;
        double radiansHeaded = DEG2RAD([self.heading doubleValue]);
        CLLocation *newLocation = [passedLocation newLoc:movedDistance along:radiansHeaded];
        coord = newLocation.coordinate;

    return coord;
}

根据要求,Object的.h文件,我没有SetCoordinate方法..

#import <Foundation/Foundation.h>
#import <CoreLocation/CoreLocation.h>
#import <MapKit/MapKit.h>

@interface TestObject : NSObject <MKAnnotation>{
    NSString *adshex;
    NSString *lat;
    NSString *lon;


    NSString …

我有以下代码泄漏.仪器说它是rssParser对象泄漏.我"刷新"XML feed并运行块并且它泄漏....

file.h

@interface TestAppDelegate : NSObject <UIApplicationDelegate> {

    NSXMLParser *rssParser;

}

file.m

NSData *data = [ NSURLConnection sendSynchronousRequest:request returningResponse: nil error: nil ];
    rssParser = [[NSXMLParser alloc] initWithData:data];
    [rssParser setDelegate:self];
    [rssParser setShouldProcessNamespaces:NO];
    [rssParser setShouldReportNamespacePrefixes:NO];
    [rssParser setShouldResolveExternalEntities:NO];
    [rssParser parse];
    [rssParser release];

泄漏的图像....

alt text http://www.shipfinder.co.uk/images/memoryleak.png

我有以下示例表...

mysql> CREATE TABLE part_date3
    ->      (  c1 int default NULL,
    ->  c2 varchar(30) default NULL,
    ->  c3 date default NULL) engine=myisam
    ->      partition by range (to_days(c3))
    -> (PARTITION p0 VALUES LESS THAN (to_days('1995-01-01')),
    -> PARTITION p1 VALUES LESS THAN (to_days('1996-01-01')) ,
    -> PARTITION p2 VALUES LESS THAN (to_days('1997-01-01')) ,
    -> PARTITION p3 VALUES LESS THAN (to_days('1998-01-01')) ,
    -> PARTITION p4 VALUES LESS THAN (to_days('1999-01-01')) ,
    -> PARTITION p5 VALUES LESS THAN (to_days('2000-01-01')) ,
    -> PARTITION p6 VALUES LESS THAN …