摘要
如何在調(diào)試中高級運用調(diào)試方法，減少重新運行
LLDB獲取幫助
調(diào)用help命令來列出LLDB所有的頂層命令
LLDB高級運用
(lldb) e int $a = 2
(lldb) p $a * 19
38
(lldb) e NSArray *$array = @[ @"Saturday", @"Sunday", @"Monday" ]
(lldb) p [$array count]
3
(lldb) po [[$array objectAtIndex:0] uppercaseString]
SATURDAY
(lldb) p [[$array objectAtIndex:$a] characterAtIndex:0]
error: no known method '-characterAtIndex:'; cast the message send to the method's return type
error: 1 errors parsing expression
//lldb無法判定某一步的計算結(jié)果是什么數(shù)據(jù)類型
(lldb) p (char)[[$array objectAtIndex:$a] characterAtIndex:0]
'M'
(lldb) p/d (char)[[$array objectAtIndex:$a] characterAtIndex:0]
77
(lldb) thread step-in // The same as "step" or "s" in GDB.
(lldb) thread step-over // The same as "next" or "n" in GDB.
(lldb) thread step-out // The same as "finish" or "f" in GDB.
(lldb) thread step-inst // The same as "stepi" / "si" in GDB.
(lldb) thread step-over-inst // The same as "nexti" / "ni" in GDB.
(lldb) thread list
(lldb) thread backtrace
(lldb) thread backtrace all //查看調(diào)用棧狀態(tài)
(lldb) thread return //命令需要一個參數(shù)來指明函數(shù)強制返回時的返回值。
//檢查幀參數(shù)和本地變量的最簡便的方式是使用frame variable命令
(lldb) frame variable
self = (SKTGraphicView *) 0x0000000100208b40
_cmd = (struct objc_selector *) 0x000000010001bae1
sender = (id) 0x00000001001264e0
selection = (NSArray *) 0x00000001001264e0
i = (NSUInteger) 0x00000001001264e0
c = (NSUInteger) 0x00000001001253b0
(lldb) frame variable self
(SKTGraphicView *) self = 0x0000000100208b40
(lldb) frame variable *self
(SKTGraphicView *) self = 0x0000000100208b40
(NSView) NSView = {
(NSResponder) NSResponder = {
...
(lldb) frame select 9
frame #9: 0x0000000100015ae3
//查看工程中使用的庫
lldb) image list
[ ?0] 432A6EBF-B9D2-3850-BCB2-821B9E62B1E0 0x0000000100000000 /Users/**/Library/Developer/Xcode/
(lldb) image lookup --address 0x0000000100000de0//具體哪一行
(lldb) image lookup --type NSURL //如果想查看具體類型
自定義執(zhí)行
執(zhí)行任意代碼
(lldb) e char *$str = (char *)malloc(128)
(lldb) e (void)strcpy($str,"wxrld of warcraft")(lldb) e $str[1] ='o'(char) $0 ='o'
(lldb) p $str(char *) $str =0x00007fd04a900040"world of warcraft"(lldb) e (void)free($str)在debugger中可以修改view的顏色、尺寸、甚至創(chuàng)建controller來push。
打印cgframe
(lldb) po self.view.frameerror: unsupported expressionwithunknowntypeerror: unsupported expressionwithunknowntypeerror:2errors parsing expression
(lldb) p (CGRect)[self.view frame](CGRect) $0= origin=(x=0, y=0) size=(width=320, height=480)
觀察watchpoint
watchpoint可以在某個變量被寫入/讀取時暫停程序運行
(lldb) watchpointsetexpression-- (int*)&_abc4Watchpoint created: Watchpoint7: addr =0x15e36d3csize=4state = enabledtype= wnewvalue:0x00000000(lldb) watchpointsetv -wread_abc4Watchpoint created: Watchpoint8: addr =0x15e36d3csize=4state = enabledtype= r ? ?watchpoint spec ='_abc4'newvalue:0(lldb) watchpointsetv -w read_write _abc3Watchpoint created: Watchpoint9: addr =0x15e36d38size=4state = enabledtype= rw ? ?watchpoint spec ='_abc3'newvalue:0
刷新UI
(lldb) po [[[UIApplication sharedApplication] keyWindow] recursiveDescription]|(lldb) e id $myView = (id)0x7f82b1d01fd0(lldb) e (void)[$myView setBackgroundColor:[UIColor blueColor]](lldb) e (void)[CATransaction flush]//必須加(lldb) e id $nvc = [[[UIApplication sharedApplication] keyWindow] rootViewController](lldb) e id $vc = [UIViewController new](lldb) e (void)[[$vc view] setBackgroundColor:[UIColor yellowColor]](lldb) e (void)[$vc setTitle:@"Yay!"](lldb) e (void)[$nvc pushViewContoller:$vc animated:YES](lldb) e (void)[CATransaction flush]
查找按鈕的 target
(lldb) po [$myButtonallTargets]{( ? ?)}
(lldb) po [$myButtonactionsForTarget:(id)0x7fb58bd2e240forControlEvent:0](_handleTap:)
