ios - What will happen when I scroll up and down UITableView because it's related to a bug I am trying to figure it out -

-

i want know happen when scroll uitableview , down. because facing bug related this. situation this, when click button, cell's avaudioplayer play audio url, , when scroll table view , down, view freeze. don't know what's caused this. trying figure out.

according dequeuereusablecellwithidentifier: documentation:

for performance reasons, table view’s data source should reuse uitableviewcell objects when assigns cells rows in tableview:cellforrowatindexpath: method. table view maintains queue or list of uitableviewcell objects data source has marked reuse. call method data source object when asked provide new cell table view. method dequeues existing cell if 1 available or creates new 1 using class or nib file registered. if no cell available reuse , did not register class or nib file, method returns nil.

that means:

when cell disappears , cell b appears , have same identifier, uikit reuse cell , returned dequeuereusablecellwithidentifier: call. if there no cell reuse - create new one.

you can use prepareforreuse method handle/prepare cell reuse.

if play audio avaudioplayer, define property in uitableviewcontroller. not create avaudioplayer object each cell.


Comments

Post a Comment

Popular posts from this blog

c - Bitwise operation with (signed) enum value -

-
i using enumerator values flags: typedef enum { = 0x00, b = 0x01u, // u has no influence, expected c = 0x02u, // u has no influence, expected ... } enum_name; volatile unsigned char* reg = someaddress; *reg |= b; according misra-c:2004 bitwise operations shall not done signed type. unfortunately, compiler iar use signed int (or short or char) underlying type of enums, , option can find relates size, not signedness ("--enum-is-int"). according iar c/c++ development guide arm , pages 169 , 211, can define type of enum s if enable iar language extensions ( -e command-line option, or project > options > c/c++ compiler > language > allow iar extensions in ide). in particular, should define "sentinel" value, make sure compiler chooses correct type. prefers signed types, , uses smallest possible integer type, sentinel should largest positive integer corresponding unsigned integer type can describe. example, typedef enum
Read more

xslt - Unnest parent nodes by child node -

-
in xml there items 0-n attributes , item should copied each attribute new item 1 attribute. given xml this: <?xml version="1.0" encoding="utf-8" ?> <items> <item> <name>a</name> <attributes> <attribute> <key>attribute1</key> <value>1</value> </attribute> </attributes> </item> <item> <name>b</name> </item> <item> <name>c</name> <attributes> <attribute> <key>attribute1</key> <value>5</value> </attribute> <attribute> <key>attribute2</key> <value>2</value> </attribute> <attribute> <key>attri
Read more

YouTubePlayerFragment cannot be cast to android.support.v4.app.Fragment -

-
im stuck on 3 days , have tried have come across after lots of searching ,this post last resort, im trying open youtubeplayerfragment using navigation drawer youtubeplayerfragment cannot cast android.support.v4.app.fragment problem edit question : have updated code have used youtubeplayersupportfragment instead of youtubeplayerfragment ,i error in displayview method (case 4: fragment = new youtube(); break;) in main activity saying cannot convert youtube fragment , cannot logcat since cant run it edit question 2: code updated again have runtime problem ,heres logcat 07-22 22:15:09.782: e/androidruntime(20603): fatal exception: main 07-22 22:15:09.782: e/androidruntime(20603): process: net.frankandwalters, pid: 20603 07-22 22:15:09.782: e/androidruntime(20603): java.lang.nullpointerexception: attempt invoke virtual method 'void com.google.android.youtube.player.youtubeplayerview.a()' on null object reference 07-22 22:15:09.782: e/androidruntime(20603): @ com.goog
Read more