Hi i am working with camera app , captured picture are shown in thumbnail-view using collection view ,i have used checkbox to select the particular picture,Example, i taken three picture , i just tapping on 1st and 2nd picture to select it will get selected ,then i am taking another two picture ,now the checkbox image moved to the latest picture ,i don't know why it happens ,
i have done this in collection view cell class , and i have created a Boolean property in same class it itself.
- (IBAction)checkButton:(id)sender {
if(!checked)
{
[self.checkBoxButton setImage:[UIImage imageNamed:#"Checkbox_checked.png"] forState:UIControlStateNormal];
checked = YES;
}
else if (checked)
{
[self.checkBoxButton setImage:[UIImage imageNamed:#"checkbox_unchecked.gif"] forState:UIControlStateNormal];
checked = NO;
}}
please help me to do this ,
If checked is declared as static, then there is only one of them which is shares by every instance of your class. You should use a property instead.
Related
Is it possible that I can change the background image of some button when I click on another button?
I basically have 10 buttons, and I want the user to know which button is currently clicked. So what happens is each button has 2 images. One for selected and one for not selected.
I want to create a function which will reset the background images of all the buttons. And in the method for each button, I will add this reset function and then change the background image of that specific button.
Can someone suggest how is that possible?
I know how to change the background image of a button when that button is clicked.
This how my buttons look:
- (IBAction)posterButton:(id)sender {}
- (IBAction)colorInvertButton:(id)sender {}
etc..
Look up the documentation for UIButton: configure each button like this:
[button setControlImage:selectedImage forState:UIControlStateSelected];
[button setControlImage:unselectedImage forState:UIControlStateNormal];
^^this can also be done in interface builder btw.
There are also the states UIControlStateNormal | UIControlStateHighlighted and UIControlStateSelected | UIControlStateHighlighted, but this is optional.
A button also has a selected state, inherited from UIControl.
If you want to have only one selected button at a time, try this (_selectedButton should be declared as an instance variable):
- (UIButton *)selectedButton {
return _selectedButton;
}
- (void)setSelectedButton:(UIButton *)b {
if(b != _selectedButton) {
_selectedButton.selected = NO;
b.selected = YES;
_selectedButton = b;
}
}
I have a UIButton that I am programmatically creating and adding to a UITableViewCell.
I have successfully set it up so that if you tap the button and keep holding it down, it will change to the image that I have set for the "highlighted state", but this is not good enough.
When the user taps the button, I need it to completely change to the new image. If the user taps the button again, I want it to change back to the original image.
I want the image to change every time they tap. Right now it changes if they tap and keep holding it down, but it switches back to the original image as soon as they are done holding it down.
Here is the code that I have so far for my buttons:
UIImage *addFriendButtonImage = [UIImage imageNamed:#"SliderThumb-Normal-G"];
UIImage *addFriendButtonImageHighlighted = [UIImage imageNamed:#"SliderThumb-Normal"];
UIButton *addFriendButton = [[UIButton alloc]init];
addFriendButton.frame = CGRectMake(237, -10, 64, 64);
[addFriendButton setImage:addFriendButtonImage forState:UIControlStateNormal];
[addFriendButton setImage:addFriendButtonImageHighlighted forState:UIControlStateHighlighted];
I also tried setting the state for the new image to "UIControlStateSelected" but all that does it make the original image a little darker. It doesn't even change to the new image, and once again it only shows it's effect if you are holding the button down.
Set the image for both the UIControlStateHighlighted and UIControlStateSelected states:
[addFriendButton setImage:addFriendButtonImage forState:UIControlStateNormal];
[addFriendButton setImage:addFriendButtonImageHighlighted forState:UIControlStateHighlighted];
[addFriendButton setImage:addFriendButtonImageHighlighted forState:UIControlStateSelected];
Then listen for UIControlEventTouchUpInside:
[addFriendButton addTarget:self action:#selector(handleTouchUpInside:) forControlEvents:UIControlEventTouchUpInside];
Then update the selected state:
- (void)handleTouchUpInside:(UIButton *)sender {
sender.selected = !sender.selected;
}
What you want is to set new image with [addFriendButton setImage:someImage forState:UIControlStateNormal]; every time the user taps on addFriendButton (look for event UIControlEventTouchUpInside).
If you want you can still assign appropriate highlight image on [addFriendButton setImage:someImage_highlighted forState:UIControlStateHighlighted];
You need to create an IBAction method for your button. If you are using a storyboard to design your view controllers go to the respective view controller in the assistant editor (tap on the icon in the upper right corner of the Xcode window), CTRL+drag the a line from the button to the .h file of your view controller's class like this:
Select Action and enter a named for the method like touchUpInsideButton.
Repeat the same steps to create a property for your button. (But select Outlet instead of Action and give your button a name like myButton.) Now you should have these two lines in your .h file:
#property (strong, nonatomic) IBOutlet UIButton *myButton;
- (IBAction)touchUpInsideButton:(id)sender;
Now go to the .m file of your view controller. Search for the newly created action method - (IBAction)touchUpInsideButton:(id)sender and enter the following code to change the button's image when the user taps the button:
- (IBAction)touchUpInsideButton:(id)sender {
UIImage *myImage = [UIImage imageNamed:#"myImageName"];
[self.myButton setImage:myImage forState:UIControlStateNormal];
}
(You can put any code inside this method that is executed whenever the user taps the button.)
I would recommend this method if you are using a storyboard. If not please refer to #Corey's reply.
The UIButton has a normal/default, highlighted, and selected image. I then have a IBAction method that is called on Touch Down. The method changes the highlighted image depending if it's selected. But when the button is selected, the method is called and so the highlight image is changed, however what is displayed is the normal/default image with a tint. I have tested that image used is in not nil. What happens is when the UIButton in a selected state is pressed displays the normal state with a tint. Why is it not using the highlight image and is there another way of showing a selected highlight image?
Why do you set the highlighted state in the IBAction method? You only need to set the highlighted image for you button when you create it. It will switch automatically. Adding a tint when selected is the default behavior of 'selection' when no highlighted image is assigned.
if your using Interface Builder, just assign the highlighted image there.
Im assuming your looking for normal button selection behavior with your IBAction method set to the touchUpInside event.
I got around this problem by using the selected state and notifications (not via the UI). When a notification is called I change image for the default state, change the selected state and then change the image for selected state.
Update:
I came up with a much better idea from another question that was doing something similar to me. The way to do it is to things in setSelected
- (void)setSelected:(BOOL)selected
{
if ( selected )
{
[self setImage:[CFCHStyleSheet imageForTickButtonChecked] forState:UIControlStateNormal];
[self setImage:[CFCHStyleSheet imageForTickButtonChecked] forState:UIControlStateSelected];
[self setImage:[CFCHStyleSheet imageForTickButtonCheckedDisabled] forState:UIControlStateDisabled];
}
else
{
[self setImage:[CFCHStyleSheet imageForTickButtonUnchecked] forState:UIControlStateNormal];
[self setImage:[CFCHStyleSheet imageForTickButtonUnchecked] forState:UIControlStateSelected];
[self setImage:[CFCHStyleSheet imageForTickButtonUncheckedDisabled] forState:UIControlStateDisabled];
}
[super setSelected:selected];
}
Is there any way I can get hold of which button I have pressed?
The buttons are created programmatically using a for loop.
I have a scroll-view of images (i used buttons for the images) where the images are taken by the user from the camera. So after the user takes a picture, the "new" picture will appear in the scrollview with the "old" pictures. The pictures are shrink into smaller sizes so what I want is that when I click the button (of any image) the image will pop up in another view in the actual size.
The button of images is created using a for loop. However, I do not know how to get hold of which button the user press. For now, when i press the button (regardless of which image/button), the last picture that is taken will always show up.
Thanks for you time.
You can use the tag property of button.
When you create the button, put a tag to each image buttons.
for(int i = 0 ; i < your_no_images ; i++){
UIButton *button = [UIButton <yourbuttontype>];
-----
button.tag = i;
[button addTarget:self action:#selector(buttonClicked:) forControlEvents:UIControlEventTouchUpInside];
[yourView addSubView:button];
}
Now in the button click action..
-(void)buttonClicked:(UIButton*)sender{
//if you has an array of UIImage's
UIImage *clickedImage = (UIImage *)[yourImageArray objectAtIndex:sender.tag];
}
IBAction methods, like those triggered upon clicking a button, include a sender argument. sender is the object that triggered the action, for example the button that was clicked. Like this:
- (IBAction)buttonWasClicked:(id)sender
{
NSLog(#"The %# button was clicked", (UIButton *)sender.currentTitle);
}
I have two buttons on my first view,so when I click on one of the button the view changes,so I have two images one for the default state and one for the selected state,
first i tried with xib,goin into the properties and changing the states and then selecting the proper images and when I build and run my code,On cliking the image doesnt change..
So I did this way through code
- (IBAction) handleButton:(id)sender
{
UIButton *button = (UIButton*)sender;
int tag = [button tag];
switch (tag)
{
case BUTTON_1:
if ([m_Button1 isSelected])
{
[m_Button2 setImage:[UIImage imageNamed:#"image.png"] forState:UIControlStateNormal];
[m_Button1 setSelected:NO];
}
else
{
[m_Button1 setImage:[UIImage imageNamed:#"image_pressed.png"] forState:UIControlStateSelected];
[m_Button1 setSelected:YES];
}
[self displaymethod1];
break;
case BUTTON_2:
[self displaymethod2];
break;
default:
break;
}
}
here the image changes when i click on it and i go to diffrent view..when i again come back to my first view,the button is still in selected mode..so How shall i fix this..
Waiting for your reply
I think is a bit simpler through IB.
When you add a regular Round Rect Button in IB you can modify its behavior by going to the Button section in the Attributes Inspector panel.
First select the images you want for it's default state by leaving the State Config in Default. There is an image and a background image properties for this. Once that is set, you can change the State Config to Highlighted and select the image you want to show when the button is highlighted.
NOTE: This is for xcode4.
when your view will appear then you have to initiate all the variable and UI property
in view will appear method. (not necessary in all cases solution is only for your requirement)
There you can set your button default state and image.
-(void)viewWillAppear:(BOOL)animated
{
[m_Button2 setImage:[UIImage imageNamed:#"image.png"] forState:UIControlStateNormal];
[m_Button1 setSelected:NO];
...
}