1 // 2 //  MainViewController.m 3 //  TableViewSreenShot 4 // 5 //  Created by ChenJungang on 14/11/8. 6 //  Copyright (c) 2014年 ChenJungang. All rights reserved. 7 // 8  9 #import "MainViewController.h"10 #import "MainCell.h"11 12 #define kTableViewRowCount 3013 #define kTableViewHeight 7614 15 @interface MainViewController ()16 @property (strong, nonatomic) IBOutlet UITableView *tableView;17 @end18 19 @implementation MainViewController20 21 - (void)viewDidLoad {22     [super viewDidLoad];23     // Do any additional setup after loading the view from its nib.24     self.title = @"screen shot";25     self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc] initWithTitle:@"share" style:UIBarButtonItemStylePlain target:self action:@selector(screenshotAction:)];26 }27 28 - (void)screenshotAction:(id)sender{29     30     NSMutableArray *indexPaths = [NSMutableArray array];31     for(NSUInteger i = 0; i < [self.tableView numberOfRowsInSection:0]; i++){32         [indexPaths addObject:[NSIndexPath indexPathForRow:i inSection:0]];33     }34     UIImage *image = [self screenShotForIndexPaths:indexPaths];35     UIActivityViewController *activityVC = [[UIActivityViewController alloc] initWithActivityItems:@[image] applicationActivities:nil];36     [self.navigationController presentViewController:activityVC animated:YES completion:NULL];37 }38 39 #pragma mark - UITableViewDataSource40 - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{41     return kTableViewRowCount;42 }43 44 - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView{45     return 1;46 }47 48 - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{49     static NSString *mainCellId = @"CellId";50     MainCell *mainCell = [tableView dequeueReusableCellWithIdentifier:mainCellId];51     if (!mainCell) {52         mainCell = [MainCell loadFromXib];53     }54     mainCell.accountNameLabel.text = [NSString stringWithFormat:@"row : %ld",(long)indexPath.row];55     return mainCell;56 }57 58 #pragma mark - UITableViewDelegate59 - (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{60     [tableView deselectRowAtIndexPath:indexPath animated:YES];61 }62 - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{63     return kTableViewHeight;64 }65 66 #pragma mark - Screen shot Method67 - (UIImage*)screenShotForIndexPaths:(NSArray*)indexPaths68 {69     CGPoint originalOffset = self.tableView.contentOffset;70 71     UIGraphicsBeginImageContextWithOptions(CGSizeMake(CGRectGetWidth(self.tableView.frame), self.tableView.rowHeight * indexPaths.count), NO, 0.0);72     CGContextRef ctx = UIGraphicsGetCurrentContext();73     74     //将cell逐个渲染到CGContext上75     MainCell *cell = nil;76     for (NSIndexPath *indexPath in indexPaths) {77         78         //找到相应位置的cell，渲染出來79         [self.tableView scrollToRowAtIndexPath:indexPath atScrollPosition:UITableViewScrollPositionNone animated:NO];80         cell = (MainCell *)[self.tableView cellForRowAtIndexPath:indexPath];81         [cell.layer renderInContext:ctx];82         83         //在context上渲染的origin84         CGContextTranslateCTM(ctx, 0, self.tableView.rowHeight);85     }86     87     UIImage *image = UIGraphicsGetImageFromCurrentImageContext();88     UIGraphicsEndImageContext();89     self.tableView.contentOffset = originalOffset;90     return image;91 }92 93 94 - (void)didReceiveMemoryWarning {95     [super didReceiveMemoryWarning];96     // Dispose of any resources that can be recreated.97 }98 99 @end