iOS UITextView載入本地html檔案例子

有時候我們不是從伺服器上直接載入一個網頁，而是需要載入本地的html檔案，具體實現的代碼如下：

- (void)viewDidLoad {
    [super viewDidLoad];
    self.view.backgroundColor = [UIColor whiteColor];
    
    //建立從Bundle中來自HTML檔案的URL
    NSURL *html = [[NSBundle mainBundle] URLForResource:@"right_obligations" withExtension:@"html"];
    
    // 用HTML建立attributedString
    NSAttributedString *attrStr = [[NSAttributedString alloc] initWithFileURL:html options:@{NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType} documentAttributes:nil error:nil];
    
    // 建立TextView，添加attributed str
    UITextView *textView = [[UITextView alloc] initWithFrame:CGRectMake(0, kHeaderHeight, kScreenWidth, kScreenHeight - kHeaderHeight)];
    textView.editable = NO;
    [textView setAttributedText:attrStr];
    [self.view addSubview:textView];
}

補充:關於 UITextView用法

//初始化並定義大小  

 UITextView *textview = [[UITextView alloc] initWithFrame:CGRectMake(20, 10, 280, 30)];
    textview.backgroundColor=[UIColor whiteColor]; //背景色
    textview.scrollEnabled = NO;    //當文字超過視圖的邊框時是否允許滑動，預設為“YES”
    textview.editable = YES;        //是否允許編輯內容，預設為“YES”
    textview.delegate = self;       //設定代理方法的實作類別
    textview.font=[UIFont fontWithName:@"Arial" size:18.0]; //設定字型名字和字型大小;
    textview.returnKeyType = UIReturnKeyDefault;//return鍵的類型
    textview.keyboardType = UIKeyboardTypeDefault;//鍵盤類型
    textview.textAlignment = NSTextAlignmentLeft; //文本顯示的位置預設為居左
    textview.dataDetectorTypes = UIDataDetectorTypeAll; //顯示資料類型的串連模式（如電話號碼、網址、地址等）
    textview.textColor = [UIColor blackColor];
    textview.text = @"UITextView詳解";//設定顯示的常值內容
    [self.view addSubview:textview];

UITextView的代理方法如下:
//將要開始編輯
- (BOOL)textViewShouldBeginEditing:(UITextView *)textView;

//將要結束編輯
- (BOOL)textViewShouldEndEditing:(UITextView *)textView;

//開始編輯
- (void)textViewDidBeginEditing:(UITextView *)textView;

//結束編輯
- (void)textViewDidEndEditing:(UITextView *)textView;

//內容將要發生改變編輯
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text;

//內容發生改變編輯
- (void)textViewDidChange:(UITextView *)textView;

//焦點發生改變
- (void)textViewDidChangeSelection:(UITextView *)textView;

有時候我們要控制項自適應輸入的文本的內容的高度，只要在textViewDidChange的代理方法中加入調整控制項大小的代理即可
 
 
- (void)textViewDidChange:(UITextView *)textView{
    //計算文本的高度
    CGSize constraintSize;
    constraintSize.width = textView.frame.size.width-16;
    constraintSize.height = MAXFLOAT;
    CGSize sizeFrame =[textView.text sizeWithFont:textView.font
                                constrainedToSize:constraintSize
                                    lineBreakMode:UILineBreakModeWordWrap];
   
 //重新調整textView的高度
    textView.frame = CGRectMake(textView.frame.origin.x,textView.frame.origin.y,textView.frame.size.width,sizeFrame.height+5);
}

 
控制輸入文字的長度和內容，可通調用以下代理方法實現
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
    if (range.location>=100)
    {
        //控制輸入文本的長度
        return  NO;
    }
    if ([text isEqualToString:@"\n"]) {
        //禁止輸入換行
        return NO;
    }
    else
    {
        return YES;
    }
}

 
UITextView退出鍵盤的幾種方式
因為iphone的軟鍵盤沒有內建的退鍵盤鍵，所以要實現退出鍵盤需要自己實現，有如下幾種方式：
1）如果你程式是有導航條的，可以在導航條上面加多一個Done的按鈕，用來退出鍵盤，當然要先實UITextViewDelegate。
 
- (void)textViewDidBeginEditing:(UITextView *)textView {
   
    UIBarButtonItem *done =    [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone
                                                                              target:self
                                                                              action:@selector(dismissKeyBoard)];
   
    self.navigationItem.rightBarButtonItem = done;
   
    [done release];
    done = nil;
   
}

- (void)textViewDidEndEditing:(UITextView *)textView { 
    self.navigationItem.rightBarButtonItem = nil;  
}

- (void)dismissKeyBoard {  
    [self.textView resignFirstResponder]; 
}

2）如果你的textview裡不用斷行符號鍵，可以把斷行符號鍵當做退出鍵盤的響應鍵。
代碼如下：

-(BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
    if ([text isEqualToString:@"\n"]) {
        [textView resignFirstResponder];
        return NO;
    }
    return YES;
}

 

 
3）還有你也可以自訂其他載入鍵盤上面用來退出，比如在彈出的鍵盤上面加一個view來放置退出鍵盤的Done按鈕。
代碼如下：

 
    UIToolbar * topView = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, 320, 30)];
    [topView setBarStyle:UIBarStyleBlack];

    UIBarButtonItem *btnSpace = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace
                                                                              target:self
                                                                              action:nil];
   
    UIBarButtonItem *doneButton = [[UIBarButtonItem alloc]initWithTitle:@"Done"
                                                                  style:UIBarButtonItemStyleDone
                                                                 target:self
                                                                 action:@selector(dismissKeyBoard)];
   
    NSArray * buttonsArray = @[btnSpace, doneButton];;
    [doneButton release];
    [btnSpace release];
    [topView setItems:buttonsArray];
    [textView setInputAccessoryView:topView];//當文本輸入框加上topView
    [topView release];
    topView = nil;

-(IBAction)dismissKeyBoard
{
    [tvTextView resignFirstResponder];
}