Shrink all views when keyboard is displayed

I am working on an app with a UISplitViewController and am wondering what the best way is to achieve the following:

开发者_C百科In the detail view I have a UITextView for editing txt files. However, one the keyboard appears on screen, I want all of the views to shrink (master and detail) to reflect the new size. Is this possible?

Thanks

Yes its possible. You need to register for the following notifications,

UIKeyboardWillShowNotification and UIKeyboardWillHideNotification.

And designate handlers for each.

Then in the handlers you need to adjust/shrink the frame of the UITextView. Note the notification will include an object with the dimensions of the keyboard. You need to use these to shrink your textview by the corresponding amount.

Here is some similar sample code you can refactor

 // Call this method somewhere in your view controller setup code.
 - (void)registerForKeyboardNotifications

{


[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(keyboardWasShown:)
                                             name:UIKeyboardDidShowNotification object:nil];

[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(keyboardWasHidden:)
                                             name:UIKeyboardDidHideNotification object:nil];

keyboardShown=NO;

}
- (void)resizeTextView
{
    float margin=[contentTextBox frame].origin.x;
    //margin=0.0;
    CGRect rect0 = [[container scrollView] frame];
    CGRect rect1 = [contentTextBox frame];
    //shrink textview if its too big to fit with textview
    if(rect0.size.height<rect1.size.height){
        rect1.size.height=rect0.size.height-2*margin;
        [contentTextBox setFrame:rect1];        
    }
    //make the textview visible if content is bigger than scroll view
    if([[container scrollView] contentSize].height>[[container scrollView] frame].size.height){
        CGPoint point = CGPointMake([[container scrollView] contentOffset].x,[contentTextBox frame].origin.y-margin);
        [[container scrollView] setContentOffset:point animated:YES];       
    }
}
- (void)keyboardWasShown:(NSNotification*)aNotification
{   
    //keyboard is already visible just exit
    if (keyboardShown)
        return;
    keyboardShown=YES;
    //resize the content text box and scroll into view
    if(activeTextView!=nil){
        [self resizeTextView];
    }
    //scroll text field into view
    if(activeTextField!=nil){
        //get the text field rectangle
        CGRect rect = [activeTextField frame];
        //adjust to the current page of the scroll view
        rect.origin.x=[[container scrollView] contentOffset].x;
        [[container scrollView] scrollRectToVisible:rect animated:YES];
    }

}
- (void)keyboardWasHidden:(NSNotification*)aNotification
{   
    //keyboard not visible just exit
    if (!keyboardShown)
        return;
    keyboardShown=NO;

    //resize the content text box
    if(contentTextBox!=nil){
        //find where the bottom of the texview should be from the label location
        CGRect rect0=[contentTextBoxBottom frame];
        //get the current frame
        CGRect rect1=[contentTextBox frame];
        //adjust width
        rect1.size.width=rect0.size.width;
        //adjust height
        rect1.size.height=rect0.origin.y-rect1.origin.y;
        //restore the size of the textview
        [contentTextBox setFrame:rect1];
    }
}