自定義的UITextView佔位符不刪除在鍵盤輸入

Question

我已經研究如何手動包括在UITextView中的佔位符文本（因爲有許多在計算器上），然而，每當我點擊的TextView並開始打字，它不會刪除佔位，我不知道爲什麼。任何幫助表示讚賞！謝謝！

#import "HusbandryAddRecord.h" 
#import <QuartzCore/QuartzCore.h> 

@interface HusbandryAddRecord() 

@end 

@implementation HusbandryAddRecord 

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil 
{ 
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]; 
    if (self) { 
    } 
    return self; 
} 

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 
    [scroller setScrollEnabled:YES]; 
    [scroller setContentSize:CGSizeMake(320, 601)]; 

    // Round The Corners of the Notes TextView 
    notesTV.clipsToBounds = YES; 
    notesTV.layer.cornerRadius = 10.0f; 

    placeholderLabel = [[UILabel alloc] initWithFrame:CGRectMake(10.0, 0.0, notesTV.frame.size.width - 20.0, 34.0)]; 
    [placeholderLabel setText:@"Notes"]; 
    [placeholderLabel setBackgroundColor:[UIColor clearColor]]; 
    [placeholderLabel setFont:[UIFont fontWithName:@"System" size:14.0]]; 
    [placeholderLabel setTextColor:[UIColor lightGrayColor]]; 

    [notesTV addSubview:placeholderLabel]; 
} 

- (void)viewDidUnload 
{ 
    [notesTV release]; 
    notesTV = nil; 
    [super viewDidUnload]; 
    // Release any retained subviews of the main view. 
} 

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation 
{ 
    return (interfaceOrientation == UIInterfaceOrientationPortrait); 
} 

- (void)dealloc { 
    [notesTV release]; 
    [super dealloc]; 
} 

- (void) textViewDidChange:(UITextView *)theTextView { 
    if(![theTextView hasText]) { 
     [theTextView addSubview:placeholderLabel]; 
     [placeholderLabel setText:@"Notes"]; 
    } 

    else if ([[theTextView subviews] containsObject:placeholderLabel]) { 
     [placeholderLabel removeFromSuperview]; 
    } 
} 

- (void)textViewDidEndEditing:(UITextView *)theTextView { 
    if (![theTextView hasText]) { 
     [theTextView addSubview:placeholderLabel]; 
    } 
} 

@end 

Answer 1

請告訴我真正發生的事情是要添加標籤，你的TextView的每個輸入查詢字符。因此，如果您鍵入字符並且條件符合，則只能刪除一個標籤，並且可以看到下面的標籤，然後再創建一個標籤。

請確保您有委託正確設置，然後使用，而不是添加和移除子視圖中隱藏屬性。

- (void)textViewDidChange:(UITextView *)textView 
{ 
    placeholderLabel.hidden = textView.hasText; 
} 

Answer 2

使用下面的代碼它會幫助你..

-(void)textViewDidChange:(UITextView *)textView 
{ 
    if([textView.text length]>0){ 
     placeholderLabel.hidden = YES; 
    }else { 
     placeholderLabel.hidden = NO; 
    } 

} 

Answer 3

您在TextView中添加placeHolderLabel輸入每個character.Have看看這個代碼： -

- (BOOL)textViewShouldBeginEditing:(UITextView *)textView 
{ 
[placeholderLabel removeFromSuperview]; 
return YES; 
} 

當你正在用的TextView文本的寫作做了這個時間寫代碼後。

-(IBAction)keyBoard:(id)sender 
{ 
if ([textView.text length]==0) 
{ 
    [textView addSubview:placeholderLabel]; 
} 
[textView resignFirstResponder]; 
} 

這個功能是按鈕，我已經把這個鍵盤的textview.On點擊外將dissmiss，它會檢查是否有TextView的文本0長度則placeHolderLabel將再次it.Hope添加它幫助。謝謝:)

Answer 4

使用lines.It工作

textviewname.editable = YES; textviewname.clearsContextBeforeDrawing = YES;

Answer 5

簡單的方法：https://stackoverflow.com/a/17451491/1442541

添加標籤TextView的和隱藏的文本時不爲空。