点击按钮改变textField的状态

创建一个TextField

//创建一个按钮,用来textfield切换状态

    UIButton *changePicbutton=[UIButtonbuttonWithType:UIButtonTypeSystem];

    changePicbutton.frame=CGRectMake(100,200, 50, 50);

    [changePicbutton setImage:[UIImageimageNamed:@"check.png"]forState:UIControlStateNormal];

    [changePicbutton addTarget:selfaction:@selector(changePic:)forControlEvents:UIControlEventTouchUpInside];

   self.isClick=NO;

    [self.windowaddSubview:changePicbutton];

-(void)changePic:(UIButton *)button

{

   if (self.isClick) {

        [button setImage:[UIImageimageNamed:@"check.png"]forState:UIControlStateNormal];

    }else{

        [button setImage:[UIImageimageNamed:@"checked.png"]forState:UIControlStateNormal];

    }

    self.isClick=!self.isClick

    ;

    self.textField.secureTextEntry=!self.textField.secureTextEntry;

}