Xcode 添加从当前位置到NSMutableArray的距离
我试图将距离当前位置的距离加载到数组中,但似乎遗漏了一些内容。My TableView仅显示?,仅当我的currentLoc不工作,但我的NSLog显示正确的位置时,才应显示。请帮忙 更新:必须已删除我的重新加载tableView,修复了?问题,但现在我只行驶了0.00公里。仍然缺少一些东西。在LocationManager中,我的currentLoc是正确的,但是当我试图计算数组中的距离时,我丢失了它Xcode 添加从当前位置到NSMutableArray的距离,xcode,ios5,cllocation,Xcode,Ios5,Cllocation,我试图将距离当前位置的距离加载到数组中,但似乎遗漏了一些内容。My TableView仅显示?,仅当我的currentLoc不工作,但我的NSLog显示正确的位置时,才应显示。请帮忙 更新:必须已删除我的重新加载tableView,修复了?问题,但现在我只行驶了0.00公里。仍然缺少一些东西。在LocationManager中,我的currentLoc是正确的,但是当我试图计算数组中的距离时,我丢失了它 #import "AuthorViewController.h" #import "Auth
#import "AuthorViewController.h"
#import "Author.h"
#import <sqlite3.h>
@implementation AuthorViewController
@synthesize theauthors;
@synthesize currentLoc;
- (void)locationManager:(CLLocationManager *)manager didUpdateToLocation:(CLLocation *)newLocation fromLocation:(CLLocation *)oldLocation
{
currentLoc = newLocation;
if (newLocation.horizontalAccuracy <= 100.0f) {
[locMgr stopUpdatingLocation];
}
NSLog(@"Lat: %f, Long: %f", currentLoc.coordinate.latitude, currentLoc.coordinate.longitude);
[self.tableView reloadData];
}
- (void)locationManager:(CLLocationManager *)manager didFailWithError:(NSError *)error
{
NSString *msg = [[NSString alloc]initWithString:@"Error obtaining location"];
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:@"Error" message:msg delegate:nil cancelButtonTitle:@"Done" otherButtonTitles:nil];
[alert show];
}
#pragma mark - View lifecycle
- (void)viewDidLoad
{
[self barList];
[super viewDidLoad];
NSLog(@"Lat2: %f, Long2: %f", currentLoc.coordinate.latitude, currentLoc.coordinate.longitude);
}
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
locMgr = [[CLLocationManager alloc] init];
locMgr.delegate = self;
[locMgr startUpdatingLocation];
}
#pragma mark - Table view data source
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
// Return the number of rows in the section.
return [self.theauthors count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
int rowCount = indexPath.row;
Author *author = [self.theauthors objectAtIndex:rowCount];
cell.textLabel.text = author.barName;
if (currentLoc == nil) {
cell.detailTextLabel.text = [NSString stringWithFormat:@"?"];
}else
{
cell.detailTextLabel.text = [NSString stringWithFormat:@"%.02f km", author.cachedDist];
}
return cell;
}
-(NSMutableArray *) barList{
theauthors = [[NSMutableArray alloc] init];
@try {
NSFileManager *fileMgr = [NSFileManager defaultManager];
NSString *dbPath = [[[NSBundle mainBundle] resourcePath ]stringByAppendingPathComponent:@"TulsaBars.sqlite"];
BOOL success = [fileMgr fileExistsAtPath:dbPath];
if(!success)
{
NSLog(@"Cannot locate database file '%@'.", dbPath);
}
if(!(sqlite3_open([dbPath UTF8String], &db) == SQLITE_OK))
{
NSLog(@"An error has occured: %@", sqlite3_errmsg(db));
}
const char *sql = "SELECT * FROM TulsaBars";
sqlite3_stmt *sqlStatement;
if(sqlite3_prepare(db, sql, -1, &sqlStatement, NULL) != SQLITE_OK)
{
NSLog(@"Problem with prepare statement: %@", sqlite3_errmsg(db));
}else{
while (sqlite3_step(sqlStatement)==SQLITE_ROW) {
Author * author = [[Author alloc] init];
author.barName = [NSString stringWithUTF8String:(char *) sqlite3_column_text(sqlStatement,1)];
author.barAddress = [NSString stringWithUTF8String:(char *) sqlite3_column_text(sqlStatement,2)];
author.barState = [NSString stringWithUTF8String:(char *) sqlite3_column_text(sqlStatement, 5)];
author.barLat = [NSString stringWithUTF8String:(char *) sqlite3_column_text(sqlStatement, 8)];
author.barLong = [NSString stringWithUTF8String:(char *) sqlite3_column_text(sqlStatement, 9)];
author.cachedDist = [NSString stringWithUTF8String:(char *) sqlite3_column_text(sqlStatement, 10)];
CLLocation *barLocation = [[CLLocation alloc] initWithLatitude:[author.barLat doubleValue] longitude:[author.barLong doubleValue]];
CLLocationDistance distancekm = [currentLoc distanceFromLocation: barLocation]/1000;
NSString *distanceString = [[NSString alloc] initWithFormat: @"%f", distancekm];
author.cachedDist = distanceString;
[theauthors addObject:author];
}
}
sqlite3_finalize(sqlStatement);
}
@catch (NSException *exception) {
NSLog(@"Problem with prepare statement: %@", sqlite3_errmsg(db));
}
@finally {
sqlite3_close(db);
return theauthors;
}
}
@end
当需要在表视图中重新绘制数据时,请确保调用[tableView reloadData]
您也可以尝试此答案中概述的扩展技术:谢谢,我一定是在什么地方删除了我的重新加载表。这解决了问题?问题是,但是现在所有的东西都只有0.00公里。你的当前LOC ivar有可能为零吗?我想这就是问题所在,我只是不明白为什么。我的Lat和Long NSLog显示正确,但我的Lat2和Long NSLog显示0渲染前是否更新了locationManager?如果有,自上次更新以来您是否调用了reloadData?如果没有,我一定是错过了它。我想这实际上是我加载数组的方式。