UI Seventh Lesson

Main content: Uiscrollview, Uipagecontrol (Use: Software introduction page, photo album ...) such as

First, Uiscrollview

Uiscrollview: Is a view that can be scrolled ( Note: UIView itself cannot scroll, subclass Uiscrollview extends the functionality of scrolling, Uiscrollview is the base class for all scrolling views )

The main expertise and two aspects:

1, scroll: Contentsize is greater than frame.size, can scroll

2, Zoom: With zoom, you can specify the zoom multiplier

Uiscrollview related properties for scrolling:

1, Contentsize: Defines the content area size, determines whether can slide

2. Contentoffset: Offset of the upper left corner of the view from the origin of the coordinates

3. Scrollstotop: Slide to the top (when sliding the scroll bar)

4, Pagingenable: Whether the whole page sliding

5, bounces: whether the border rebound

6. Scrollenable: Is it possible to scroll

7, Showshorizontalscrolllndicator: Control whether to show the horizontal direction of the scroll bar

8, Showsverticalscrolllndicator: Control whether to show the vertical direction of the scroll bar

9, Alwaysbouncehorizontal: Control horizontal direction encountered whether the border rebound

10, Alwaysbouncevertical: Control vertical direction to see if the frame bounces

Uiscrollview related properties for scaling

1, Minimumzoomscale: The minimum scale of scaling

2, Maximumzoomscale: magnification of the largest proportion

3, Zoomscale: Set the change ratio

4, zooming: to determine whether the scaling rebound

5, Bounceroom: control when the zoom will rebound

Note: To achieve scaling, you also need to implement delegate, which specifies who the zoomed view is

Uiscrollview Rolling Agent method

//scrolling will trigger

-(void) Scrollviewdidscroll: (Uiscrollview *) ScrollView

//triggers when dragging starts

-(void) scrollviewwillbegindragging: (Uiscrollview *) ScrollView

trigger at end of drag/pull

-(void) scrollviewdidenddragging: (Uiscrollview *) ScrollView willdecelerate: (BOOL) decelerate

//start to slow down when triggered

-(void) scrollviewwillbegindecelerating: (Uiscrollview *) ScrollView

//end-of-deceleration trigger (when stopped)

-(void) scrollviewdidenddecelerating: (Uiscrollview *) ScrollView

Proxy methods for scaling:

//Complete zoom in and zoom out trigger

-(void) scrollviewdidendzooming: (Uiscrollview *) ScrollView Withview: (UIView *) View Atscale: (float) scale

//Specifies that a Uiscrollview sub-view can be scaled down

-(UIView *) Viewforzoominginscrollview: (Uiscrollview *) ScrollView

Second, Uipagecontrol

Uipagecontrol: Used to indicate which page is currently, usually used in conjunction with Uiscrollview

Related properties:

CurrentPage: Current Page

Numberofpages: Specify the number of pages

Uipagecontrol can see from the class name that its parent class is Uicontrol, and all can add events to it like a button, except that the event trigger is no longer uicontroleventstouchupinside, But uicontroleventsvaluechanged.

Iii. examples of use of Uiscrollview and Uipagecontrol

//Create Uiscrollview Object
Uiscrollview *scrollview = [[Uiscrollview alloc] Initwithframe:cgrectmake (0, 0, Self.view.bounds.size.width, Self.view.bounds.size.height)];

//Add to view
[Self addsubview:scrollview];

//Set background color
Scrollview.background = [Uicolor Redcolor];

//Set the slide bar to display the horizontal
Self.showhorizontalscrollindicator = YES;

//Set the size of the content view
Scrollview.containsize = Cgsizemake (ScrollView.bounds.size.width * i, scrollView.bounds.size.height);//How many pictures, I is how much

//Set the full page slide of the picture
scrollview.pagingenabled = YES;

//Add images to Uiscrollview
for (int i = 0; i < count; i++) {
Uiimageview *imageview = [[Uiimageview alloc] initwithimage:[uiimage imagenamed:@ "%d", I]];
//Set the size of the picture
Imageview.frame = CGRectMake ((i-1) * self.frame.size.width, 0, Self.frame.size.width, self.frame.size.height);

//Add to ScrollView
[ScrollView Addsubview:imageview];

//Release
[ImageView release], ImageView = nil;
}

//Add Page Controller
//Create Objects
Uipagecontroller *pagecontrol = [[[[Uipagecontroller alloc] init] autorelease];

//Set Location
Pagecontrol.frame = CGRectMake (0, self.view.frame.size.height-40, Self.view.frame.size.width, 30);

//Set the number of dots (pages)
Pagecontrol.numberofpages = 10;

//Set which dot is currently at
Pagecontrol.currentpage = 2;

//The color of the shop that is not selected
Pagecontrol.pageindicatortintcolor = [Uicolor Redcolor];

//Color of the current point point
Pagecontrol.currentpageindicatortintcolor = [Uicolor Bluecolor];

//Set Listener events
[Pagecontrol addtarget:self Action: @selector (pagecontrolaction:) forcontrolevents:uicontroleventvaluechanged];//

//Add to view
[Self.view Addsubview:pagecontrol];


#pragma mark-implementing-pagecontrolaction: Monitoring Events
-(void) Pagecontrolaction: (Uipagecontrol *) Sender {
//enable Uiscrollview to make corresponding slide display
Cgsize viewsize = _userguidescrollview.frame.size;
CGRect rect = CGRectMake (sender.currentpage * viewsize.width, 0, Viewsize.width, viewsize.height);
[_userguidescrollview Scrollrecttovisible:rect Animated:yes];
}


#pragma mark-Override the Proxy method in----scrollviewdelegate to implement sliding
-(void) scrollviewdidenddecelerating: (Uiscrollview *) ScrollView {
//Calculate offset
int index = ABS (scrollview.contentoffset.x/scrollview.frame.size.width);
//Set Pagecontrol according to offset
_scrollpagecontrol.currentpage = index;
}


#pragma mark-Override----Dealloc method
-(void) Dealloc {

//Release properties of memory
[_scrollpagecontrol release], _scrollpagecontrol = nil;
[_userguidescrollview release], _userguidescrollview = nil;

//Call the Dealloc method of the parent class
[Super Dealloc];
}

UI Seventh Lesson