我UITextfied在点击文本键盘时使用,但是当我按下return键时,键盘没有消失.我使用了以下代码:
func textFieldShouldReturn(textField: UITextField!) -> Bool // called when 'return' key pressed. return NO to ignore.
{
return true;
}
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resignfirstresponder方法没有进入功能.
struct ContentView: View {
var body: some View {
Text("Hello World")
}
}
struct contentView_Previews: PreviewProvider {
static var previews: some View {
ContentView()
}
}
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为了以Struct为起点,我们将在视图上设计的所有UI都将在Struct内部,并且我们知道Struct是值类型,并且它将在堆栈中分配内存。
就内存而言,它将如何影响?
视图对象没有进入addsubview括号
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: NSDictionary?) -> Bool
{
// Override point for customization after application launch.
UIApplication.sharedApplication().setStatusBarHidden(true, animated: true);
var myView = UIView(frame:CGRectMake(0, 200, 320, 100));
myView.backgroundColor = UIColor.redColor()
self.window.?.addSubview(myView)
return true
}
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