iphone开发我的新浪微博客户端-用户登录等待篇(1.4)

   

      本篇在上一篇的基础上完成如上（图2） 所示的用户登录等待功能，首先说说这个页面功能的由来，这个就是当检查sqlite库中已经存在用户账号的时候从表中把用户记录查询出来，然后从 NSUserDefaults中获取上一次登录的账号，如果查询出来的用户记录中包含上一次登录的账号，那么就把这个账号作为默认显示账号，如果没有就取 用户记录中的第一个账号作为默认显示账号，上一篇中当用户完成OAuth认证把账号信息保存到sqlite库后也是显示这个页面功能。

      先来看看UI是怎么实现了，看上图这个界面包含用户头像小图标、用户名称、3个功能按钮（添加、切换、删除）这三部分元素，我的做法是把这三部分元素添加 到一个单独的UIView上，并且把这个UIView背景设置成透明，然后把这个UIView显示在上一篇的LoginViewController的 View之上，这样UIView就有了背景图了，背景图由底下的LoginViewController的View提供。同时上一篇中在做 LoginViewController有个遗漏忘记讲给LoginViewController的View添加背景图了，这里补上，做法是如下：

      补上一篇：双击LoginViewController.xib文件，开启IB后双击LoginViewController.xib的View打开，然 后从Library面板中拖一个Image View组件到这个View上并且把这个Image View尺寸设置跟View一样大，然后为这个Image View设置一张背景图，如下图：

补上上面的内容后，现在回到正题继续讲本篇的功能。

     一、上面讲到了新建一个单独的UIView作为本功能的界面，这里先新建名为SelectViewController的 UIViewController subclass类型的类文件，新建的时候记得勾上With XIB user interface选项。

     二、打开上步新建的SelectViewController.h文件,声明一个UIButton作为用户头像小图标，一个UILabel作为用户名 称，还有delegate和onClick用来调用LoginViewController中的方法用，还有这还import了一个名为 UICustomSegmentedControl.h的文件，这个是一个自定义的组件，用来实现上面提到的3个按钮的功能，该组件和系统自带的 UISegmentedControl组件类似，至于为什么非要自己做一个而不用系统自带理由和前面的UIDialogWindow一样，文章最后我会把 这个组件的代码贴出来这里就不解释了直接使用这个组件，具体代码如下：

    
    
    
    

     
     
     
     #import <UIKit/UIKit.h>
#import "Global.h"
#import "UICustomSegmentedControl.h"
@interface SelectViewController : UIViewController<UICustomSegmentedControlDelegate> {
 IBOutlet UIButton *iconBtn;
 IBOutlet UILabel *nameLabel;
 id delegate;
 SEL onClick;
}
@property(nonatomic,retain)IBOutlet UIButton *iconBtn;
@property(nonatomic,retain)IBOutlet UILabel *nameLabel;
@property(nonatomic,retain)id delegate;
-(id)initWithDelegate:(id)aDelegate onClick:(SEL)aOnClick;
@end
    
    
    
    

     三、双击SelectViewController.xib用IB打开，Library面板中拖一个UIButton和UILabel到View中间合 适的位置同时做好连接操作，分别连接到SelectViewController.h中的iconBtn和nameLabel，并且把View的 background设置成clear color然后保存，如下图：

     四、打开SelectViewController.m文件，首先是initWithDelegate方法，这个方法主要是设置SelectViewController的delegate和delegate，代码如下：

    
    
    
    

     
     
     
     -(id)initWithDelegate:(id)aDelegate onClick:(SEL)aOnClick;
{
 if (self=[super init]) {
 self.delegate=aDelegate;
 onClick=aOnClick;
 }
 return self;
}
    
    
    
    

     五、接下来我们要设置一下用户头像小图标（iconBtn）白色方框背景和默认用户小图标，实现代码非常简单了，在viewDidLoad方法里添加如下代码：

    
    
    
    

     
     
     
     [iconBtn setBackgroundImage:[[Global pngWithPath:@"icon_bg"]stretchableImageWithLeftCapWidth:8.0 topCapHeight:7.0] forState:UIControlStateNormal];
 [iconBtn setBackgroundImage:[[Global pngWithPath:@"icon_h_bg"] stretchableImageWithLeftCapWidth:8.0 topCapHeight:7.0] forState:UIControlStateHighlighted];
 [iconBtn setImage:[Global pngWithPath:@"user_icon"] forState:UIControlStateNormal];
 [iconBtn setImage:[Global pngWithPath:@"user_icon"] forState:UIControlStateHighlighted];
    
    
    
    

     六、接下来我们要实现3个功能按钮（添加、切换、删除），前面提到了这功能是由自定义组件UICustomSegmentedControl实现的，在 viewDidLoad方法里实例化一个UICustomSegmentedControl并且添加到SelectViewController的 View中间适当位置，UICustomSegmentedControl实例化的时候需要5个参数，分别子按钮个数、子按钮尺寸、子按钮之间分隔图片、 tag属性、delegate属性，代码如下：

    
    
    
    

     
     
     
     UICustomSegmentedControl *segmented=[[UICustomSegmentedControl alloc] initWithSegmentCount:3 segmentsize:CGSizeMake(85.0f, 46.0f) dividerImage:[Global pngWithPath:@"line"] tag:99909 delegate:self];
 segmented.center=CGPointMake(self.view.bounds.size.width/2,self.view.bounds.size.height-64);
 [self.view addSubview:segmented];
 [segmented release];
    
    
    
    

     七、UICustomSegmentedControl组件使用还没有完，还需要实现几个方法，代码如下：

    
    
    
    

     
     
     
     //构造子按钮
-(UIButton*)buttonFor:(UICustomSegmentedControl*)segmentedControl atIndex:(NSUInteger)segmentIndex;
{
 UIButton* button = [UIButton buttonWithType:UIButtonTypeCustom];
 button.frame = CGRectMake(0.0f, 0.0f, segmentedControl.segmentSize.width, segmentedControl.segmentSize.height);
 button.adjustsImageWhenHighlighted = NO;
 button.titleLabel.font=[UIFont systemFontOfSize:15.0f];
 [button setTitleColor:[UIColor colorWithRed:50.0f/255.0f green:79.0f/255.0f blue:133.0f/255.0f alpha:1.0f] forState:UIControlStateNormal];
 
 if (segmentIndex==0) {
 [button setBackgroundImage:[[Global pngWithPath:@"left_btn"]stretchableImageWithLeftCapWidth:10.0 topCapHeight:23.0] forState:UIControlStateNormal];
 [button setBackgroundImage:[[Global pngWithPath:@"left_h_btn"] stretchableImageWithLeftCapWidth:10.0 topCapHeight:23.0] forState:UIControlStateHighlighted];
 [button setImage:[Global pngWithPath:@"add"] forState:UIControlStateNormal];
 //[button setImage:[Global pngWithPath:@"add"] forState:UIControlStateHighlighted];
 [button setTitle:@"添加" forState:UIControlStateNormal];
 
 }else if (segmentIndex==1) {
 [button setBackgroundImage:[[Global pngWithPath:@"center_btn"]stretchableImageWithLeftCapWidth:1.0 topCapHeight:23.0] forState:UIControlStateNormal];
 [button setBackgroundImage:[[Global pngWithPath:@"center_h_btn"] stretchableImageWithLeftCapWidth:1.0 topCapHeight:23.0] forState:UIControlStateHighlighted];
 [button setImage:[Global pngWithPath:@"change"] forState:UIControlStateNormal];
 //[button setImage:[Global pngWithPath:@"change"] forState:UIControlStateHighlighted];
 [button setTitle:@"切换" forState:UIControlStateNormal];
 }
 else {
 [button setBackgroundImage:[[Global pngWithPath:@"right_btn"]stretchableImageWithLeftCapWidth:1.0 topCapHeight:23.0] forState:UIControlStateNormal];
 [button setBackgroundImage:[[Global pngWithPath:@"right_h_btn"] stretchableImageWithLeftCapWidth:1.0 topCapHeight:23.0] forState:UIControlStateHighlighted];
 [button setImage:[Global pngWithPath:@"del"] forState:UIControlStateNormal];
 //[button setImage:[Global pngWithPath:@"del"] forState:UIControlStateHighlighted];
 [button setTitle:@"删除" forState:UIControlStateNormal];
 }
 return button;
}

//子按钮点击事件
-(void)touchUpInsideSegmentIndex:(NSUInteger)segmentIndex
{
 NSNumber *index=[NSNumber numberWithInteger:segmentIndex];
 [delegate performSelector:onClick withObject:index];
}

//子按钮点击按下去事件
-(void)touchDownAtSegmentIndex:(NSUInteger)segmentIndex
{
 
}
    
    
    
    

     八、完成了SelectViewController后，接下来就是在LoginViewController中调用显示这个 SelectViewController，打开LoginViewController.m文件找到上一篇中我们写的 -(void)showUserInfo方法，在这个方法中就是检查sqlite库中是否有账号记录，上一篇就是没有账号记录的情况，在 showUserInfo方法显示弹出窗口提示用户进行授权认证，现在在这个方法中补上有账号记录的情况，那么就调用调用显示这个 SelectViewController，代码如下：

    
    
    
    

     
     
     
     //如果数据库中已经有帐号记录那么取第一条用户信息进行显示，否则显示授权认证开始对话框
-(void)showUserInfo
{
 Sqlite *sqlite=[[Sqlite alloc] init];
 self.userList=[sqlite getUserList]; 
 [sqlite release];
 if (self.userList) {
 if ([self.userList count]!=0)
 {
 //无账号记录的情况，显示弹出窗口提示用户进行授权认证
 
 }else {
 User *u=[self.userList objectAtIndex:0];
    
    
    
    
    
    
    
    

     
     
     
      //获取上一次的登录用户记录
 NSString *uid=[[NSUserDefaults standardUserDefaults] objectForKey:@"selectUID"];
 NSLog(@"id:%@",uid);
 if (uid!=nil) {
 for (User *obj in userList) {
 if ([obj.userId isEqualToString:uid] ) {
 u=obj;
 break;
 }
 }
 }
 if (!selectViewController) {
 selectViewController=[[SelectViewController alloc] initWithDelegate:self onClick:@selector(btnBarOnClick:) ];
 [self.view addSubview:selectViewController.view];
 }
 //
 [self setShowUserInfo:u];
 
 }

 
 }else {
 NSLog(@"no");
 }
 
}
    
    
    
    

上面方法中实例化了一个SelectViewController并且添加到了当 前view中，还有一个知识点就是从NSUserDefaults获取上一次登录的用户账号id，在后面的文章中会有提到每次用登录的时候都会在 NSUserDefaults保存登录账号的id，方便下一次登录时作为默认用户。

     九、在上面的方法中最后调用了[self setShowUserInfo:u]方法，把默认账号的小图标头像和名称显示在SelectViewController的view中，代码如下：

    
    
    
    

     
     
     
     //设置显示用户图标和名字
-(void)setShowUserInfo:(User *)u
{
 [selectViewController.nameLabel setText:u.name];
 [selectViewController.iconBtn setImage:u.icon forState:UIControlStateNormal];
 [selectViewController.iconBtn setImage:u.icon forState:UIControlStateHighlighted];
 [selectViewController.iconBtn addTarget:self action:@selector(login:) forControlEvents:UIControlEventTouchUpInside];
}
    
    
    
    

     十、在上面的代码中给小图标头像按钮添加了一个login:事件，也就是点击这个小图标后会以这个账号登录微博，至于登录功能我们在以后的文章中实现了，本篇已经完成了任务了。

     请继续关注后续的文章，谢谢！！！

     ps:UICustomSegmentedControl组件代码如下：

    
    
    
    

     
     
     
     //
// UICustomSegmentedControl.h
// MinBlog4Sina
//
// Created by 水的右边 on 11-5-17.
// Copyright 2011 http://www.cnblogs.com/hll2008/ All rights reserved.
//

#import <Foundation/Foundation.h>
@class UICustomSegmentedControl;

@protocol UICustomSegmentedControlDelegate
-(UIButton*)buttonFor:(UICustomSegmentedControl*)segmentedControl atIndex:(NSUInteger)segmentIndex;
-(void)touchUpInsideSegmentIndex:(NSUInteger)segmentIndex;
-(void)touchDownAtSegmentIndex:(NSUInteger)segmentIndex;
@end

@interface UICustomSegmentedControl : UIView {
 NSMutableArray* buttons;
 NSObject <UICustomSegmentedControlDelegate> *delegate;
 CGSize segmentSize;
}
@property (nonatomic, retain) NSMutableArray* buttons;
@property (nonatomic,assign)CGSize segmentSize;

-(id)initWithSegmentCount:(NSUInteger)segmentCount segmentsize:(CGSize)segmentsize dividerImage:(UIImage*)dividerImage tag:(NSInteger)objectTag delegate:(NSObject <UICustomSegmentedControlDelegate>*)customSegmentedControlDelegate;

@end
    
    
    
    

    
    
    
    

     
     
     
     //
// UICustomSegmentedControl.m
// MinBlog4Sina
//
// Created by 水的右边 on 11-5-17.
// Copyright 2011 http://www.cnblogs.com/hll2008/ All rights reserved.
//

#import "UICustomSegmentedControl.h"
@implementation UICustomSegmentedControl
@synthesize buttons;
@synthesize segmentSize;

-(id)initWithSegmentCount:(NSUInteger)segmentCount segmentsize:(CGSize)segmentsize dividerImage:(UIImage*)dividerImage tag:(NSInteger)objectTag delegate:(NSObject <UICustomSegmentedControlDelegate>*)customSegmentedControlDelegate
{
 if (self=[super init]) {
 segmentSize=segmentsize;
 self.tag=objectTag;
 delegate=customSegmentedControlDelegate;
 self.frame = CGRectMake(0, 0, (segmentsize.width * segmentCount) + (dividerImage.size.width * (segmentCount - 1)), segmentsize.height);
 self.buttons = [[NSMutableArray alloc] initWithCapacity:segmentCount];
 
 CGFloat horizontalOffset = 0;
 for (NSUInteger i=0; i<segmentCount; i++) {
 UIButton *button=[delegate buttonFor:self atIndex:i];
 
 [button addTarget:self action:@selector(touchDownAction:) forControlEvents:UIControlEventTouchDown];
 [button addTarget:self action:@selector(touchUpInsideAction:) forControlEvents:UIControlEventTouchUpInside];
 [button addTarget:self action:@selector(otherTouchesAction:) forControlEvents:UIControlEventTouchUpOutside];
 [button addTarget:self action:@selector(otherTouchesAction:) forControlEvents:UIControlEventTouchDragOutside];
 [button addTarget:self action:@selector(otherTouchesAction:) forControlEvents:UIControlEventTouchDragInside];
 
 [buttons addObject:button];
 button.frame = CGRectMake(horizontalOffset, 0.0, button.frame.size.width, button.frame.size.height);
 [self addSubview:button];
 
 if (i != segmentCount - 1)
 {
 UIImageView* divider = [[[UIImageView alloc] initWithImage:dividerImage] autorelease];
 divider.frame = CGRectMake(horizontalOffset + segmentsize.width, 0.0, dividerImage.size.width, dividerImage.size.height);
 [self addSubview:divider];
 }
 horizontalOffset = horizontalOffset + segmentsize.width + dividerImage.size.width;
 }
 }
 return self;
}

-(void)setButtonState:(UIButton *)selectedButton
{
 //for (UIButton * button in buttons) {
 // if (button==selectedButton) {
 // button.selected=YES;
 //button.highlighted=button.selected? NO:YES;
 // }else {
 // button.selected=NO;
 //button.highlighted=NO;
 // }

 //}
}

-(void)touchDownAction:(UIButton*)button
{
 [self setButtonState:button];
 
 if ([delegate respondsToSelector:@selector(touchDownAtSegmentIndex:)])
 {
 [delegate touchDownAtSegmentIndex:[buttons indexOfObject:button]];
 }
}

-(void)touchUpInsideAction:(UIButton*)button
{
 [self setButtonState:button];
 
 if ([delegate respondsToSelector:@selector(touchUpInsideSegmentIndex:)])
 {
 [delegate touchUpInsideSegmentIndex:[buttons indexOfObject:button]];
 }
}

-(void)otherTouchesAction:(UIButton*)button
{
 [self setButtonState:button];
}


-(void)dealloc
{
 [buttons release];
 [super dealloc];
}

@end