UIButtonのラベルを複数行にする
testbutton.layer.borderWidth=1.0;
[testbutton setTitle:@"あいうえお\nかきくけこ" forState:UIControlStateNormal];
UILabel*innerLabel= testbutton.titleLabel;
innerLabel.numberOfLines=0;
innerLabel.frame=CGRectMake(0, 0, testbutton.frame.size.width, testbutton.frame.size.height);