窗口背景随弹窗的出现而渐变

之前写都是点击弹窗的时候直接将背景变成半透明，但是客户要求进行渐变

一、使用Activity.getWindow().setAttributes()方法来实现

工具代码灵活使用

1、窗口渐变工具代码

实现渐变的代码如下

public class WindowsBgAlpha {    private Activity mActivity;    Handler handler = new Handler();    public WindowsBgAlpha(Activity activity) {        this.mActivity = activity;    }    /**     * 设置添加屏幕的背景透明度,     * 在给定的时间内渐变     */    private float currentAlpha ;    private boolean isAdd = false;    public void backgroundAlpha(float startBgAlpha, final float endBgAlpha, long time) {        //计算，实现渐变过程        int end = (int) (endBgAlpha * 10);        int start = (int) (startBgAlpha * 10);        final int num ; //时间分为几份        if (start>end){            isAdd = false;            num = start - end;        }else {            isAdd = true;            num = end - start;        }        final long mTime = (time / num);//每段变化使用的时长        final WindowManager.LayoutParams lp = mActivity.getWindow().getAttributes();        currentAlpha = startBgAlpha;        handler.postDelayed(new Runnable() {            @Override            public void run() {                if (isAdd){                    currentAlpha += 0.1;                    if (currentAlpha>endBgAlpha){                        handler.removeCallbacks(this);                    }else {                        handler.postDelayed(this,mTime);                    }                }else {                    currentAlpha -= 0.1;                    if (currentAlpha<endBgAlpha){                        handler.removeCallbacks(this);                    }else {                        handler.postDelayed(this,mTime);                    }                }                lp.alpha = currentAlpha; //0.0-1.0                mActivity.getWindow().setAttributes(lp);            }        }, mTime);    }}

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2、和弹窗一起使用

随弹窗的出现而进行渐变，主要就是这个方法backgroundAlpha(float startBgAlpha, final float endBgAlpha, long time)

private void showPopupWindow() {        View showView = LayoutInflater.from(BarrierActivity.this).inflate(R.layout.sub_popup_window, null);        popupWindow = new PopupWindow(showView, ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT, true);        popupWindow.setTouchable(true);        popupWindow.setAnimationStyle(R.style.AnimationPopup);          //一定要在代码中setBackgroundDrawable，不然点击外面popupWindow是不会dismiss的        popupWindow.setBackgroundDrawable(getResources().getDrawable(R.drawable.choose_sub_shape));        View v = LayoutInflater.from(BarrierActivity.this).inflate(R.layout.activity_brkthough, null);        ImageView menuDown = (ImageView) showView.findViewById(R.id.menu_down);        menuDown.setOnClickListener(new View.OnClickListener() {            @Override            public void onClick(View v) {                popupWindow.dismiss();            }        });        popupWindow.showAtLocation(v, Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL, 0, 0);        new WindowsBgAlpha(BarrierActivity.this).backgroundAlpha(1.0f, 0.6f, 200);        popupWindow.setOnDismissListener(new poponDismissListener());        RecyclerView recyclerView = (RecyclerView) showView.findViewById(R.id.recycler_view);        TextView popupTime = (TextView) showView.findViewById(R.id.popup_time);        long nowTime = clockUtils.getNowTime();        clockUtils.stopTime();        clock = new ClockUtils(nowTime, handler, popupTime);        clock.startTime();        ChooseSubjectAdapter adapter = new ChooseSubjectAdapter(BarrierActivity.this, mData, totalCount, new ChooseSubjectAdapter.ItemClickListener() {            @Override            public void onClick(View v) {                int tag = (int) v.getTag();                brkthoughActivityViewpager.setCurrentItem(tag, true);                popupWindow.dismiss();            }        });        recyclerView.setAdapter(adapter);        recyclerView.setLayoutManager(new GridLayoutManager(this, 5));    }    class poponDismissListener implements PopupWindow.OnDismissListener {        @Override        public void onDismiss() {            //这里的时间最好和窗口进出时动画执行时间一致            new WindowsBgAlpha(BarrierActivity.this).backgroundAlpha(0.6f, 1.0f, 300);            if (clock!=null){                long nowTime = clock.getNowTime();                clock.stopTime();                if (nowTime==0){                    bottomTime.setText("00:00");                }else {                    clockUtils.refreshTime(nowTime);                }            }        }    }

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二 、 通过给Dialog设置style来实现渐变

    //color    <color name="tram">#00000000</color>    //animal    <style name="DialogAnimation">        <item name="android:windowEnterAnimation">@anim/abc_slide_in_bottom</item>        <item name="android:windowExitAnimation">@anim/abc_slide_out_bottom</item>    </style>    <style name="dialog_style" parent="android:Theme.Dialog">        <item name="android:windowNoTitle">true</item>        <item name="android:windowBackground">@color/tram</item>        <item name="android:windowAnimationStyle">@style/DialogAnimation</item>    </style>

abc_slide_in_bottom

<translate xmlns:android="http://schemas.android.com/apk/res/android"           android:interpolator="@android:anim/decelerate_interpolator"           android:fromYDelta="50%p" android:toYDelta="0"           android:duration="@android:integer/config_mediumAnimTime"/>

abc_slide_out_bottom

<translate xmlns:android="http://schemas.android.com/apk/res/android"           android:interpolator="@android:anim/accelerate_interpolator"           android:fromYDelta="0" android:toYDelta="50%p"           android:duration="@android:integer/config_mediumAnimTime"/>