Block Value passing

Defining block is the same as defining delegate. It is defined in the class on the page on which the expected value is obtained.

For example: Class A and Class B, if I want to pass the value in Class A to Class B, I will define block in Class A and Class B ....

　　

For example:

Step 1:

In Class:

. H file:

# Import "baseviewcontroller. H"

// Define the block

Typedef void (^ addcommunity) (uiimage * IMG, nsstring * Title );

@ Interface moreviewcontroller: baseviewcontroller

@ Property (nonatomic, copy) addcommunity adds;

-(Void) addcommunitywithblock :( addcommunity) addblock;

. M file:

-(Void) viewdidload

{

[Super viewdidload];

// Do any additional setup after loading the view.

Imgview = [[[uiimageview alloc] initwithframe: cgrectmake (100,100,100,100)];

Nsstring * IMG = @ "market-android.png ";

Imgview. Image = [uiimage imagenamed: img];

[Self. View addsubview: imgview];

 

Lbltitle = [[uilabel alloc] initwithframe: cgrectmake (135,230,100, 30)];

Lbltitle. Text = @ "title ";

Lbltitle. textcolor = [uicolor redcolor];

[Self. View addsubview: lbltitle];

Uibutton * BTN = [[uibutton alloc] initwithframe: cgrectmake (100,300,100, 30)];

[BTN settitle: @ "add" forstate: uicontrolstatenormal];

[BTN addtarget: Self action: @ selector (ADD) forcontrolevents: uicontroleventtouchupinside];

[BTN setbackgroundcolor: [uicolor redcolor];

[Self. View addsubview: BTN];

}

-(Void) add {

_ Adds (imgview. Image, lbltitle. Text); // block the value

[Self. navigationcontroller poptorootviewcontrolleranimated: Yes];

}

-(Void) addcommunitywithblock :( addcommunity) addblock {

_ Adds = addblock;

}

Step 2:

Class B:

. M file:

[More addcommunitywithblock: ^ (uiimage * IMG, nsstring * Title ){

Nsdictionary * DIC = [nsdictionary dictionarywithobject: IMG forkey: title];

}];

Call block where you need to use the value. Description: More is an alias of Class. In this way, the value of page B is passed to the nsdictionary of page ....... I think it's clear! Hey ......