一个简单的 CommentView ,模仿网易新闻评论框

CommentView.swift

//
//  CommentView.swift
//  GuilinLegal
//
//  Created by Haizhen Lee on 15/7/2.
//  Copyright (c) 2015年 banxi1988 . All rights reserved.
//

import UIKit

func animationCurveToOptions(curve:UIViewAnimationCurve) -> UIViewAnimationOptions{
    switch curve{
    case .EaseInOut:
        return UIViewAnimationOptions.CurveEaseInOut
    case .EaseIn:
        return UIViewAnimationOptions.CurveEaseIn
    case .EaseOut:
        return UIViewAnimationOptions.CurveEaseOut
    case .Linear:
        return UIViewAnimationOptions.CurveLinear
    }
}


class CommentView : UIView,UITextViewDelegate{
    @IBOutlet weak var cancelButton: UIButton!
    
    @IBOutlet weak var submitButton: UIButton!
    
    @IBOutlet weak var textView: UITextView!
    let commentViewHeight: CGFloat = 160
    
    override func awakeFromNib() {
        super.awakeFromNib()
        textView.delegate = self
        submitButton.enabled = false
        self.frame = CGRect(x: 0, y: screenHeight - commentViewHeight, width: screenWidth, height: commentViewHeight)
    }
    
    func textViewDidChange(textView: UITextView) {
        submitButton.enabled = !textView.text.isEmpty
    }
    
    static func initFromNib() -> CommentView{
       return UINib(nibName: "CommentView", bundle: nil).instantiateWithOwner(self, options: nil).first as! CommentView
    }
    
    func show(){
        self.frame = CGRect(x: 0, y: screenHeight - commentViewHeight, width: screenWidth, height: commentViewHeight)
       let keyWindow = UIApplication.sharedApplication().keyWindow
        keyWindow?.addSubview(self)
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardFrameWillChange:", name: UIKeyboardWillChangeFrameNotification, object: nil)
        textView.becomeFirstResponder()
    }
    
    func keyboardFrameWillChange(notification:NSNotification){
        NSLog("keyboardFrameWillChange \(notification)")
        let userInfo = notification.userInfo!
        let duration = userInfo[UIKeyboardAnimationDurationUserInfoKey]!.doubleValue
        let curve = userInfo[UIKeyboardAnimationCurveUserInfoKey]!.integerValue
        var options = UIViewAnimationOptions.TransitionFlipFromBottom
        if let animCurve = UIViewAnimationCurve(rawValue: curve){
            options = animationCurveToOptions(animCurve)
        }
        
        let keyboardEndFrame = userInfo[UIKeyboardFrameEndUserInfoKey]!.CGRectValue()
        UIView.animateWithDuration(0.25, delay: 0, options: options, animations: { () -> Void in
            let keyboardY = keyboardEndFrame.origin.y
            self.frame = CGRect(x: 0, y: keyboardY - self.commentViewHeight, width: screenWidth, height: screenHeight)
            }, completion: { (finished) -> Void in
        })
    }
    
    func dismiss(){
        textView.resignFirstResponder()
        removeFromSuperview()
    }
    
    @IBAction func onCancelPressed(sender: AnyObject) {
        dismiss()
    }
    
    @IBAction func onSubmitPressed(sender: AnyObject) {
        dismiss()
    }
    
    
    
}

CommentView.xib

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<document type="com.apple.InterfaceBuilder3.CocoaTouch.XIB" version="3.0" toolsVersion="7706" systemVersion="14E26a" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES">
    <dependencies>
        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="7703"/>
        <capability name="Constraints to layout margins" minToolsVersion="6.0"/>
    </dependencies>
    <objects>
        <placeholder placeholderIdentifier="IBFilesOwner" id="-1" userLabel="File's Owner"/>
        <placeholder placeholderIdentifier="IBFirstResponder" id="-2" customClass="UIResponder"/>
        <view contentMode="scaleToFill" id="iN0-l3-epB" customClass="CommentView" customModule="GuilinLegal" customModuleProvider="target">
            <rect key="frame" x="0.0" y="0.0" width="320" height="160"/>
            <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
            <subviews>
                <button opaque="NO" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="aS2-a3-hfZ">
                    <rect key="frame" x="8" y="8" width="30" height="30"/>
                    <state key="normal" title="取消">
                        <color key="titleColor" red="0.068509414790000001" green="0.068507365880000004" blue="0.068508528169999999" alpha="1" colorSpace="calibratedRGB"/>
                        <color key="titleShadowColor" white="0.5" alpha="1" colorSpace="calibratedWhite"/>
                    </state>
                    <connections>
                        <action selector="onCancelPressed:" destination="iN0-l3-epB" eventType="touchUpInside" id="Twb-jL-eEa"/>
                    </connections>
                </button>
                <button opaque="NO" contentMode="scaleToFill" contentHorizontalAlignment="center" contentVerticalAlignment="center" buttonType="roundedRect" lineBreakMode="middleTruncation" translatesAutoresizingMaskIntoConstraints="NO" id="xTp-BU-lal">
                    <rect key="frame" x="282" y="8" width="30" height="30"/>
                    <state key="normal" title="发送">
                        <color key="titleColor" red="0.068509414790000001" green="0.068507365880000004" blue="0.068508528169999999" alpha="1" colorSpace="calibratedRGB"/>
                        <color key="titleShadowColor" white="0.5" alpha="1" colorSpace="calibratedWhite"/>
                    </state>
                    <connections>
                        <action selector="onSubmitPressed:" destination="iN0-l3-epB" eventType="touchUpInside" id="AUe-PY-hUa"/>
                    </connections>
                </button>
                <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" text="写评论" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="aQp-H1-fcG">
                    <rect key="frame" x="139" y="12.5" width="51" height="20.5"/>
                    <fontDescription key="fontDescription" type="system" pointSize="17"/>
                    <color key="textColor" red="0.068509414790000001" green="0.068507365880000004" blue="0.068508528169999999" alpha="1" colorSpace="calibratedRGB"/>
                    <nil key="highlightedColor"/>
                </label>
                <textView clipsSubviews="YES" multipleTouchEnabled="YES" contentMode="scaleToFill" translatesAutoresizingMaskIntoConstraints="NO" id="9sx-5D-yby">
                    <rect key="frame" x="8" y="46" width="304" height="99"/>
                    <color key="backgroundColor" white="1" alpha="1" colorSpace="calibratedWhite"/>
                    <fontDescription key="fontDescription" type="system" pointSize="14"/>
                    <textInputTraits key="textInputTraits" autocapitalizationType="sentences"/>
                </textView>
            </subviews>
            <color key="backgroundColor" white="0.96289620007554155" alpha="1" colorSpace="calibratedWhite"/>
            <constraints>
                <constraint firstItem="aS2-a3-hfZ" firstAttribute="leading" secondItem="iN0-l3-epB" secondAttribute="leadingMargin" id="AJo-1z-grE"/>
                <constraint firstAttribute="bottom" secondItem="9sx-5D-yby" secondAttribute="bottom" constant="15" id="I9d-w3-dmQ"/>
                <constraint firstAttribute="trailingMargin" secondItem="9sx-5D-yby" secondAttribute="trailing" id="IZS-tk-Rkt"/>
                <constraint firstItem="9sx-5D-yby" firstAttribute="leading" secondItem="iN0-l3-epB" secondAttribute="leadingMargin" id="Kh8-2n-PlZ"/>
                <constraint firstItem="xTp-BU-lal" firstAttribute="trailing" secondItem="iN0-l3-epB" secondAttribute="trailingMargin" id="R7T-bD-5ws"/>
                <constraint firstAttribute="centerX" secondItem="aQp-H1-fcG" secondAttribute="centerX" constant="-4.5" id="TK1-OL-233"/>
                <constraint firstItem="xTp-BU-lal" firstAttribute="top" secondItem="iN0-l3-epB" secondAttribute="top" constant="8" id="dQo-Pp-gUt"/>
                <constraint firstItem="aS2-a3-hfZ" firstAttribute="baseline" secondItem="aQp-H1-fcG" secondAttribute="baseline" id="eP6-G6-GEt"/>
                <constraint firstItem="aS2-a3-hfZ" firstAttribute="top" secondItem="iN0-l3-epB" secondAttribute="top" constant="8" id="fRY-CX-Moi"/>
                <constraint firstItem="9sx-5D-yby" firstAttribute="top" secondItem="xTp-BU-lal" secondAttribute="bottom" constant="8" id="gwT-1u-cx2"/>
            </constraints>
            <nil key="simulatedStatusBarMetrics"/>
            <freeformSimulatedSizeMetrics key="simulatedDestinationMetrics"/>
            <connections>
                <outlet property="cancelButton" destination="aS2-a3-hfZ" id="oLZ-aC-wfh"/>
                <outlet property="submitButton" destination="xTp-BU-lal" id="1lC-uR-TUW"/>
                <outlet property="textView" destination="9sx-5D-yby" id="fcp-I5-McV"/>
            </connections>
        </view>
    </objects>
</document>