UITextview viewWithTag - 更新文本不工作，雖然我知道我有權訪問它

Question

嘿，那裏，你的善意幫助一個小問題。

我有一個UITextView與標籤

// Text view 
UITextView *currentPage = [[UITextView alloc] initWithFrame:CGRectMake(10, 10, 300.0, 194.0)]; 
currentPage.scrollEnabled = YES; 
currentPage.textAlignment = UITextAlignmentLeft; 

currentPage.tag = 100; 
currentPage.editable = NO; 
currentPage.text = @"All is sweet"; 

[self.view addSubview:currentPage]; 
[currentPage release]; 

一段時間後，我想改變上述「當前頁」文本和替換它的內容有一些新的文本。

-(void)loadNewPage{ 
// works fine, meaning I am "touching" the right object 
[self.view viewWithTag:100].alpha = 0.5f; 

// So why this one isn't legal syntax ? 
//[self.view viewWithTag:100].text = @"A new updated text"; 

} 

的viewWithTag正常工作，而改變α，因此我在想關於申請文本更新正確的語法...

Answer 1

-viewWithTag:方法返回的UIView對象，所以要設置特定於性能UITextview你應該明確地投入它的類型：

((UITextView*)[self.view viewWithTag:100]).text = @"A new updated text";