navigation bar item button样式

 UIButton *BackBtn = [[UIButton alloc] initWithFrame:CGRectMake(0.0, 100.0, 62.0, 29.0)]; [BackBtn setImage:[UIImage imageNamed:@"BackBtn.png"] forState:UIControlStateNormal]; [BackBtn addTarget:self action:@selector(BackAction:) forControlEvents:UIControlEventTouchUpInside]; UIBarButtonItem *BackBarBtn = [[UIBarButtonItem alloc] initWithCustomView:BackBtn]; NavBar.topItem.leftBarButtonItem = BackBarBtn;     [BackBtn release]; [BackBarBtn release]; 

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