Performance optimization for iOS development UITableView

One,. Reusing cells

In the data source method, repeat the drawing on the visible page

oc Method -(UITableViewCell *) TableView: (UITableView *) TableView Cellforrowatindexpath: (Nsindexpath *) Indexpath; Swift method override func TableView (Tableview:uitableview, Cellforrowatindexpath Indexpath:nsindexpath)- > UITableViewCell

Therefore, you can do some processing in this method

Static NSString *  "reusedcellid";   * Cell =private"reusedcellid"= Tableview.dequeuereusablecellwithidentifier (Reusedcellid, Forindexpath:indexpath)

This will prevent the cell from being created indefinitely, reusing the cell

　　

Second, the cell image asynchronous loading

When the image is loaded asynchronously, the picture of the cell is executed in the child thread, but if it declines at this point, there will be a lag.

Workaround:

Download the image in the following two ways,

// when the drag is over -(void) scrollviewdidenddragging: (Uiscrollview *) ScrollView willdecelerate: (BOOL) decelerate//  deceleration time -(void) scrollviewdidenddecelerating: (Uiscrollview *) ScrollView

Specific operation:

 //  Gets the visible part of the object  Nsarray *visiblepaths = [Self.tableview indexpathsforvisiblerows];  for 　　(Nsindexpath *indexpath in   Visiblepaths) {  //  Gets the DataSource inside the object, And that you do not need to load the  <code>-(UITableViewCell *) TableView: (UITableView *) TableView Cellforrowatindexpath: (Nsindexpath *) Indexpath 
 { if  (self.tableView.dragging = = NO && self.tableView.decelerating == NO) { // Span style= "color: #008000;" > start loading the picture asynchronously  <code>}  

Third, minimize the use of transparent layers

The internal rendering mechanism

Performance optimization for iOS development UITableView