Question

在我的应用程序中我有一个UITextView，在inputAccessory视图中我有一些按钮可以让用户输入Bold，Italics等。

当我点击粗体按钮时，我添加了粗体字体的属性，但UItextView中没有文本，因此所选范围始终为（0,0）。我应该使用什么作为选定的范围，以便我可以以粗体输入即将到来的文本。当我再次点击粗体按钮时，它应该删除粗体字体属性并让用户再次键入普通字体。这是我正在使用的代码：

-(void)addOrRemoveFontTraitWithName:(NSString *)traitName andValue:(uint32_t)traitValue {

    NSRange selectedRange = [self.commentsTextView selectedRange];


    NSDictionary *currentAttributesDict;
    if (selectedRange.location==0 && selectedRange.length==0) {
        //currentAttributesDict = [self.commentsTextView.textStorage attributesAtIndex:selectedRange.location effectiveRange:nil];
    }
    else{
        currentAttributesDict = [self.commentsTextView.textStorage attributesAtIndex:selectedRange.location
                                                                                    effectiveRange:nil];
    }

    UIFont *currentFont;
    if (currentAttributesDict.count >0) {
        currentFont = [currentAttributesDict objectForKey:NSFontAttributeName];
    }
    else{
        currentFont = [UIFont fontWithName:@"Sans-Regular" size:20.0f];
    }
    //currentFont = [currentAttributesDict objectForKey:NSFontAttributeName];
    UIFontDescriptor *fontDescriptor = [currentFont fontDescriptor];

    NSString *fontNameAttribute = [[fontDescriptor fontAttributes] objectForKey:UIFontDescriptorNameAttribute];
    UIFontDescriptor *changedFontDescriptor;

    if ([fontNameAttribute rangeOfString:traitName].location == NSNotFound) {
        uint32_t existingTraitsWithNewTrait = [fontDescriptor symbolicTraits] | traitValue;
        changedFontDescriptor = [fontDescriptor fontDescriptorWithSymbolicTraits:existingTraitsWithNewTrait];
    }
    else{
        uint32_t existingTraitsWithoutTrait = [fontDescriptor symbolicTraits] & ~traitValue;
        changedFontDescriptor = [fontDescriptor fontDescriptorWithSymbolicTraits:existingTraitsWithoutTrait];
    }

    UIFont *updatedFont = [UIFont fontWithDescriptor:changedFontDescriptor size:0.0];

    NSDictionary *dict = @{NSFontAttributeName: updatedFont};

    /*NSMutableDictionary * combined = [[NSMutableDictionary alloc]init];
    [combined setObject:updatedFont forKey:NSFontAttributeName];
    [combined setObject:[NSNumber numberWithInt:1] forKey:NSUnderlineStyleAttributeName];*/
    NSRange newRange = NSMakeRange(0, 10000);
    [self.commentsTextView.textStorage beginEditing];
    [self.commentsTextView.textStorage setAttributes:dict range:newRange];
    [self.commentsTextView.textStorage endEditing];
}

Answer 1

我想使用setTypingAttributes:可能会对您有所帮助。同样的解释是here。

如何将属性添加到空TextView？

1 个答案: