17 common codes

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1. code used to determine whether the email format is correct

// Use regular expression for verification

-(Bool) isvalidateemail :( nsstring *) email

{

Nsstring * emailregex = @ "[A-Z0-9a-z. _ % +-] [email protected] [A-Za-z0-9.-] + \. [A-Za-Z] {2, 4 }";

Nspredicate * emailtest = [nspredicate predicatewithformat: @ "Self matches % @", emailregex];

Return [emailtest evaluatewithobject: email];

}

2. Image Compression

Usage: uiimage * yourimage = [self imagewithimagesimple: Image scaledtosize: cgsizemake (210.0, 210.0)];

// Compress the image

-(Uiimage *) imagewithimagesimple :( uiimage *) image scaledtosize :( cgsize) newsize

{

// Create a graphics image Context

Uigraphicsbeginimagecontext (newsize );

// Tell the old image to draw in this newcontext, with the desired

// New Size

[Image drawinrect: cgrectmake (0, 0, newsize. Width, newsize. Height)];

// Get the new image from the context

Uiimage * newimage = uigraphicsgetimagefromcurrentimagecontext ();

// End the context

Uigraphicsendimagecontext ();

// Return the new image.

Return newimage;

}

3. Test the available image upload code.

-(Ibaction) uploadbutton :( ID) sender {

Uiimage * image = [uiimage imagenamed: @ "1.jpg"]; // image name

Nsdata * imagedata = uiimagejpegrepresentation (image, 0.5); // compression ratio

Nslog (@ "Bytes: % I", [imagedata length]);

// Post URL

Nsstring * urlstring = @ "http: // 192.168.1.113: 8090/text/uploadservlet ";

// Server address

// Setting up the request object now

Nsmutableurlrequest * request = [[nsmutableurlrequest alloc] init];

[Request seturl: [nsurl urlwithstring: urlstring];

[Request sethttpmethod: @ "Post"];

//

Nsstring * boundary = [nsstring stringwithstring: @ "--------------------------- 14737809831466499882746641449"];

Nsstring * contenttype = [nsstring stringwithformat: @ "multipart/form-data; boundary = % @", boundary];

[Request addvalue: contenttype forhttpheaderfield: @ "Content-Type"];

//

Nsmutabledata * Body = [nsmutabledata data];

[Body appenddata: [[nsstring stringwithformat: @ "\ r \ n -- % @ \ r \ n", boundary] datausingencoding: nsutf8stringencoding];

[Body appenddata: [[nsstring stringwithstring: @ "content-Disposition: Form-data; name = \" userfile \"; filename = \ "2.png \" \ r \ n "] datausingencoding: nsutf8stringencoding]; // name of the uploaded Image

[Body appenddata: [[nsstring stringwithstring: @ "Content-Type: Application/octet-stream \ r \ n"] datausingencoding: nsutf8stringencoding];

[Body appenddata: [nsdata datawithdata: imagedata];

[Body appenddata: [[nsstring stringwithformat: @ "\ r \ n -- % @ -- \ r \ n", boundary] datausingencoding: nsutf8stringencoding];

[Request sethttpbody: body];

// Nslog (@ "1-body: % @", body );

Nslog (@ "2-Request: % @", request );

Nsdata * returndata = [nsurlconnection sendsynchronousrequest: Request returningresponse: Nil error: Nil];

Nsstring * returnstring = [[nsstring alloc] initwithdata: returndata encoding: nsutf8stringencoding];

Nslog (@ "3-Test output: % @", returnstring );

4. load images to imageview

Uiimage * myimage = [uiimage imagenamed: @ "1.jpg"];

[Imageview setimage: myimage];

[Self. View addsubview: imageview];

5. operations on the Image Library

Select album:

Uiimagepickercontrollersourcetypesourcetype = uiimagepickercontrollersourcetypecamera;

If (! [Uiimagepickercontrollerissourcetypeavailable: uiimagepickercontrollersourcetypecamera]) {

Sourcetype = uiimagepickercontrollersourcetypephotolibrary;

}

Uiimagepickercontroller * picker = [[uiimagepickercontrolleralloc] init];

Picker. Delegate = self;

Picker. allowsediting = yes;

Picker. sourcetype = sourcetype;

[Self presentmodalviewcontroller: picker animated: Yes];

Selected:

-(Void) imagepickercontroller :( uiimagepickercontroller *) pickerdidfinishpickingmediawithinfo :( nsdictionary *) info

{

[Picker dismissmodalviewcontrolleranimated: Yes];

Uiimage * image = [info objectforkey: uiimagepickercontrollereditedimage];

[Self defined mselector: @ selector (selectpic :) withobject: imageafterdelay: 0.1];

}

-(Void) selectpic :( uiimage *) Image

{

Nslog (@ "image % @", image );

Imageview = [[uiimageview alloc] initwithimage: Image];

Imageview. Frame = cgrectmake (0, 0, image. Size. Width, image. Size. Height );

[Self. viewaddsubview: imageview];

[Self validate mselectorinbackground: @ selector (detect :) withobject: Nil];

}

Detect is a method defined by the user. The effect to be achieved after the photo is edited and selected

Unselect:

-(Void) imagepickercontrollerdidcancel :( uiimagepickercontroller *) picker

{

[Picker dismissmodalviewcontrolleranimated: Yes];

}

6. jump to the next view

Nextwebview = [[webviewcontroller alloc] initwithnibname: @ "webviewcontroller" Bundle: Nil];

[Self presentmodalviewcontroller: nextwebview animated: Yes];

// Create a button on the Right of uibarbuttonitem

Uibarbuttonitem * rightbutton = [[uibarbuttonitem alloc] initwithtitle: @ "right" style: uibarbuttonitemstyledone target: Self action: @ selector (clickrightbutton)];

[Self. navigationitem setrightbarbuttonitem: rightbutton];

Set navigationbar to hide

Self. navigationcontroller. navigationbarhidden = yes ;//

Automatic line feed (automatic LINE folding) for multiple lines of uilabel in iOS development)

Uiview * footerview = [[uiview alloc] initwithframe: cgrectmake (10,100,300,180)];

Uilabel * label = [[uilabel alloc] initwithframe: cgrectmake (10,100,300,150)];

Label. Text = @ "Hello world! Hello world! Hello world! Hello world! Hello world! Hello world! Hello world! Hello world! Hello world! Hello world! Hello world! Hello world! Hello world! Helloworld! ";

// The background color is red.

Label. backgroundcolor = [uicolor redcolor];

// Set the font color to white

Label. textcolor = [uicolor whitecolor];

// Text center display

Label. textalignment = uitextalignmentcenter;

// Automatic LINE folding settings

Label. linebreakmode = uilinebreakmodewordwrap;

Label. numberoflines = 0;

7. Code Generation button

Cgrect frame = cgrectmake (0,400, 72.0, 37.0 );

Uibutton * button = [uibutton buttonwithtype: uibuttontyperoundedrect];

Button. Frame = frame;

[Button settitle: @ "New button" forstate: uicontrolstatenormal];

Button. backgroundcolor = [uicolor clearcolor];

Buttons. Tag = 2000;

[Button addtarget: Self action: @ selector (buttonclicked :) forcontrolevents: uicontroleventtouchupinside];

[Self. View addsubview: button];

8. display a widget in the center of the View

(A control, such as label and view) label. Center = self. View. Center;

9. Nice-looking text processing

Take the cell textlabel in tableview as an example:

Cell. backgroundcolor = [uicolorscrollviewtexturedbackgroundcolor];

// Set the text font

Cell. textlabel. font = [uifont fontwithname: @ "americantypewriter" Size: 100366f];

// Set the text color

Cell. textlabel. textcolor = [uicolor orangecolor];

// Set the background color of the text

Cell. textlabel. shadowcolor = [uicolor whitecolor];

// Set the text display position

Cell. textlabel. textalignment = uitextalignmentcenter;

10. Hide the status bar

The reader may know a simple method, that is, adding

[[Uiapplication sharedapplication] setstatusbarhidden: Yes animated: No];

11. Change the alertview background

Uialertview * thealert = [[uialertviewalloc] initwithtitle: @ "atention"

Message: @ "I'm a Chinese! "

Delegate: Nil

Cancelbuttontitle: @ "cancel"

Otherbuttontitles: @ "okay", nil] autorelease];

[Thealert show];

Uiimage * theimage = [uiimageimagenamed: @ "lovechina.png"];

TheImage = [theimage stretchableimagewithleftcapwidth: 0 topcapheight: 0];

Cgsize thesize = [thealert frame]. size;

Uigraphicsbeginimagecontext (thesize );

[Theimage drawinrect: cgrectmake (5, 5, thesize. width-10, thesize. height-20)]; // adjust the size of this place to adapt to the background color of alertview.

TheImage = uigraphicsgetimagefromcurrentimagecontext ();

Uigraphicsendimagecontext ();

Thealert. layer. Contents = (ID) [theimage cgimage];

12. Transparent keyboard

Textfield. keyboardappearance = uikeyboardappearancealert;

Indicates whether the network active firewheel in the status bar is rotated.

[Uiapplication sharedapplication]. networkactivityindicatorvisible. The default value is no.

13. capture screen images

// Create a bitmap-based image context and specify the size as cgsizemake (200,400)

Uigraphicsbeginimagecontext (cgsizemake (200,400 ));

// Renderincontext presents the receiver and Its subrange to the specified context

[Self. View. layer renderincontext: uigraphicsgetcurrentcontext ()];

// Returns an image based on the current image context.

Uiimage * aimage = uigraphicsgetimagefromcurrentimagecontext ();

// Remove the image context at the top of the stack based on the current bitmap

Uigraphicsendimagecontext ();

// Return the data of the specified image in PNG format

Imagedata = uiimagepngrepresentation (aimage );

14. Change the background of the cell.

Uiview * myview = [[uiview alloc] init];

Myview. Frame = cgrecctmake (0, 0,320, 47 );

Myview. backgroundcolor = [uicolorcolorwithpatternimage: [uiimage imagenamed: @ "0006.png"];

Cell. selectedbackgroundview = myview;

15. display images

Cgrect myimagerect = cgrectmake (0.0f, 0.0f, 3200000f, 109.0f );

Uiimageview * myimage = [[uiimageview alloc] initwithframe: myimagerect];

[Myimage setimage: [uiimage imagenamed: @ "myimage.png"];

Myimage. opaque = yes; // whether opaque is transparent

[Self. View addsubview: myimage];

16. Adjust the image size to the frame size without confirmation)

Nsstring * ImagePath = [[nsbundle mainbundle] pathforresource: @ "xcodecrash" oftype: @ "PNG"];

Uiimage * image = [[uiimage alloc] initwithcontentsoffile: ImagePath];

Uiimage * newimage = [Image transformwidth: 80.f Height: 240.f];

Uiimageview * imageview = [[uiimageview alloc] initwithimage: newimage];

[Newimagerelease];

[Image release];

[Self. View addsubview: imageview];

17. Code for clicking an image to jump: generate a button with a background image and bind the button with the desired event!

Uibutton * imgbutton = [uibutton alloc] initwithframe: cgrectmake (0, 0,120,120)];

[Imgbutton setbackgroundimage :( uiimage *) [self. imgarray objectatindex: indexpath. Row] forstate: uicontrolstatenormal];

Imgbutton. Tag = [indexpath row];

[Imgbutton addtarget: Self action: @ selector (buttonclick :) forcontrolevents: uicontroleventtouchupinside];

 

 

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17 common codes