實現背景透明度漸變的效果，類似於分享底部的彈出框

這是公司最近寫的一個專案，其中的一個自定義分享模組，剛開始實現的效果比較簡單，背景透明度沒有漸變，而是隨著底部分享的彈出框而一起彈出，看起來比較生硬，使用者體驗不是很好，現在要實現的效果就是類似於SharedSDK底部分享彈出框的效果，相信大家都用過SharedSDK，也見過他的分享彈出框的效果！廢話不多說了，看張效果圖，然後直接上程式碼！

程式碼塊

1.這個是主介面

package com.example.bg.share.selfdefinitionshareanimaiton;

import android.animation.Animator;
import
 
 android.animation.ObjectAnimator;
import android.content.Context;
import android.graphics.drawable.ColorDrawable;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.Gravity;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import
 
 android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.PopupWindow;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private Button bt_share;
    private ImageView iv_all
 
;
    private static PopupWindow mPop;
    private View mPopupView;
    private PopupWindow mPopupWindow;
    private LinearLayout qzone;
    private LinearLayout friend_circle;
    private LinearLayout sina;
    private LinearLayout weixin_goodfriend;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        initView();
        initData();
        initEventListener();
    }

    private void initView() {
        bt_share = (Button) findViewById(R.id.bt_share);
        iv_all = (ImageView) findViewById(R.id.iv_all);

        /**
         * 分享的那個popupWindow
         */
        //獲取得到PopupWindow的佈局檔案
        mPopupView = View.inflate(this, R.layout.layout_share_popupwindow, null);
        qzone = (LinearLayout) mPopupView.findViewById(R.id.qzone);
        friend_circle = (LinearLayout) mPopupView.findViewById(R.id.friend_circle);
        sina = (LinearLayout) mPopupView.findViewById(R.id.sina);
        weixin_goodfriend = (LinearLayout) mPopupView.findViewById(R.id.weixin_goodfriend);
    }

    private void initData() {
    }

    private void initEventListener() {
        bt_share.setOnClickListener(this);
        qzone.setOnClickListener(this);
        friend_circle.setOnClickListener(this);
        sina.setOnClickListener(this);
        weixin_goodfriend.setOnClickListener(this);

    }

    @Override
    public void onClick(View view) {
        switch(view.getId()) {
           case R.id.bt_share: //分享
               propetyAnim(iv_all);
               mPopupWindow = showPopWindow(view, mPopupView, this, iv_all);
               break;
            case R.id.qzone://分享到qq空間！

               break;
            case R.id.friend_circle://分享到微信朋友圈！

               break;
            case R.id.sina://分享到新浪微博！

               break;
            case R.id.weixin_goodfriend://分享到微信好友！

               break;
           default:
               break;
        }
    }

    /**
        半透明背景出現的動畫
     */
    private void propetyAnim(ImageView iv) {
        ObjectAnimator animator = ObjectAnimator.ofFloat(iv, "alpha", 0, 0.2f, 0.5f, 0.7f, 0.9f, 1);
        animator.setDuration(500);
        animator.setRepeatCount(0);
        animator.start();
        iv.setVisibility(View.VISIBLE);
    }

    /**
     * 半透明背景消失的動畫
     * @param iv
     */
    public static void propetyAnim2(final ImageView iv){
        ObjectAnimator animator = ObjectAnimator.ofFloat(iv,"alpha",1,0.9f,0.7f,0.5f,0.2f,0);
        animator.setDuration(500);
        animator.setRepeatCount(0);
        animator.start();
        animator.addListener(new Animator.AnimatorListener() {
            @Override
            public void onAnimationStart(Animator animation) {

            }

            @Override
            public void onAnimationEnd(Animator animation) {
                iv.setVisibility(View.GONE);
            }

            @Override
            public void onAnimationCancel(Animator animation) {

            }

            @Override
            public void onAnimationRepeat(Animator animation) {

            }
        });
    }

    /**
     * 顯示PopupWindow
     * @param parent
     * @param view
     * @return
     */
    public static PopupWindow showPopWindow(View parent, View view, Context context, final ImageView iv_all) {
        mPop = new PopupWindow(view,
                ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
        mPop.setOutsideTouchable(true);
        mPop.setFocusable(true);
        mPop.setBackgroundDrawable(new ColorDrawable(0));
        mPop.setAnimationStyle(R.style.AnimBottom);
        mPop.showAtLocation(parent, Gravity.TOP, 0, 0);

        //mPop.showAsDropDown(v,0,0);
        view.setFocusable(true); // 這個很重要
        view.setFocusableInTouchMode(true);

        mPop.setOnDismissListener(new PopupWindow.OnDismissListener() {
            @Override
            public void onDismiss() {
                propetyAnim2(iv_all);
                mPop = null;
            }
        });

        // 重寫onKeyListener
        view.setOnKeyListener(new View.OnKeyListener() {

            @Override
            public boolean onKey(View v, int keyCode, KeyEvent event) {
                if (keyCode == KeyEvent.KEYCODE_BACK) {
                    mPop.dismiss();
                    return true;
                }
                return false;
            }
        });

        // 點選其他地方消失
        view.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                // TODO Auto-generated method stub
                if (mPop != null && mPop.isShowing()) {
                    mPop.dismiss();
                }
                return false;
            }
        });

        return mPop;
    }



}

2.這個是主介面的佈局檔案

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <Button
        android:id="@+id/bt_share"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:text="分享"/>
    <ImageView
        android:id="@+id/iv_all"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="#44000000"
        android:visibility="gone">
    </ImageView>
</RelativeLayout>

3.這個是PopupWindow的佈局檔案

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@android:color/transparent"
    android:orientation="vertical">

    <View
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1" />

    <LinearLayout
        android:id="@+id/ll"
        android:layout_width="match_parent"
        android:layout_height="235dp"
        android:orientation="vertical">

        <View
            android:id="@+id/view1"
            android:layout_width="match_parent"
            android:layout_height="1dp"
            android:background="@color/layout_bg" />

        <View
            android:id="@+id/child_top"
            android:layout_width="match_parent"
            android:layout_height="20dp"
            android:background="@android:color/white" />

        <LinearLayout
            android:id="@+id/ll_share_item"
            android:layout_width="match_parent"
            android:layout_height="140dp"
            android:background="@android:color/white"
            android:orientation="horizontal">

            <LinearLayout
                android:id="@+id/qzone"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:orientation="vertical">

                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center"
                    android:src="@drawable/qzone" />

                <TextView
                    android:id="@+id/tv1"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center"
                    android:layout_marginTop="10dp"
                    android:gravity="center"
                    android:text="QQ空間"
                    android:textSize="14sp" />
            </LinearLayout>

            <LinearLayout
                android:id="@+id/friend_circle"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:orientation="vertical">

                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center"
                    android:src="@drawable/friend_cirle" />

                <TextView
                    android:id="@+id/tv2"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center"
                    android:layout_marginTop="10dp"
                    android:gravity="center"
                    android:text="朋友圈"
                    android:textSize="14sp" />
            </LinearLayout>

            <LinearLayout
                android:id="@+id/sina"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:orientation="vertical">

                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center"
                    android:src="@drawable/sina_weibo" />

                <TextView
                    android:id="@+id/tv3"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center"
                    android:layout_marginTop="10dp"
                    android:gravity="center"
                    android:text="新浪微博"
                    android:textSize="14sp" />
            </LinearLayout>

            <LinearLayout
                android:id="@+id/weixin_goodfriend"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:orientation="vertical">

                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center"
                    android:src="@drawable/weixin_goodfriend" />

                <TextView
                    android:id="@+id/tv4"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_gravity="center"
                    android:layout_marginTop="10dp"
                    android:gravity="center"
                    android:text="微信好友"
                    android:textSize="14sp" />
            </LinearLayout>

        </LinearLayout>

        <View
            android:layout_width="match_parent"
            android:layout_height="20dp"
            android:layout_below="@id/ll"
            android:background="#22000000" />

        <View
            android:id="@+id/view2"
            android:layout_width="match_parent"
            android:layout_height="1dp"
            android:background="@color/layout_bg" />

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:background="@color/white"
            android:id="@+id/rl_cancel">

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerInParent="true"
                android:gravity="center"
                android:text="取消"
                android:textColor="#0000ff"
                android:textSize="15sp" />

        </RelativeLayout>

        <View
            android:layout_width="match_parent"
            android:layout_height="1dp"
            android:background="@color/layout_bg" />

    </LinearLayout>
</LinearLayout>

4.在colors.xml中加入這兩種顏色

    <color name="white">#ffffff</color>
    <color name="layout_bg">#f0f0f0</color>

5.在styles.xml中加入這個樣式

     <!--自定義分享的底部彈出-->
    <style name="AnimBottom" parent="@android:style/Animation">
        <item name="android:windowEnterAnimation">@anim/push_bottom_in</item>
        <item name="android:windowExitAnimation">@anim/push_bottom_out</item>
    </style>

對應的兩種動畫
1）push_bottom_in

<?xml version="1.0" encoding="utf-8"?>
<!-- 上下滑入式 -->
<set xmlns:android="http://schemas.android.com/apk/res/android" >

    <translate
        android:duration="280"
        android:fromYDelta="100%p"
        android:toYDelta="0"        
     />   
     <alpha
        android:fromAlpha="0.0"
        android:toAlpha="1.0"
        android:duration="200"
    />     
</set>

2)push_bttom_out

<?xml version="1.0" encoding="utf-8"?>
<!-- 上下滑入式 -->
<set xmlns:android="http://schemas.android.com/apk/res/android" >


    <translate
        android:duration="280"
        android:fromYDelta="0"
        android:toYDelta="50%p" />
    <alpha
        android:fromAlpha="1.0"
        android:toAlpha="0.0"
        android:duration="200"
    />  
</set>

好的到這裡已ok，本人技術水平有限，如有錯誤，歡迎各位大牛指正！