1、点击右上角三个点的图标，在界面底部弹出一个区域，这个区域有一些按钮提供给我们操作

2、当该区域出现的时候，详情界面便灰了，也说成透明度变化了

3、当任意选了一个按钮或者点击了该区域以外的部分，该区域消失，灰色界面变回亮白色，并执行点击的按钮对应的操作

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context=".MainActivity"

    android:id="@+id/mainlayout"

    >

    <ImageButton

        android:id="@+id/btn_more"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:src="@mipmap/btn_more"

        android:background="#0000"

        android:layout_alignParentRight="true"

        android:layout_margin="5dp"

        />

</RelativeLayout>

 * 自定义PopupWindow ， 实现仿QQ空间分享效果

 */

public class SelectPopupWindow extends PopupWindow {

    //一个LinearLayout 表示一个可选操作

    private LinearLayout fp_hide_all,fp_hide_pic,fp_report,fp_linear_sharetoWeixin,fp_linear_sharetoquan,fp_linear_sharetoQzone,fp_linear_sharetoQQ;

    //popupWindow 取消文本按钮

    private TextView fp_cancel;

    private View mMenuView;

    public SelectPopupWindow(Activity context, OnClickListener itemsOnClick) {

        super(context);

        LayoutInflater inflater = (LayoutInflater) context

                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        mMenuView = inflater.inflate(R.layout.feed_popuwindow, null);

        fp_hide_pic = (LinearLayout) mMenuView.findViewById(R.id.fp_hide_pic);

        fp_hide_all = (LinearLayout) mMenuView.findViewById(R.id.fp_hide_all);

        fp_report = (LinearLayout) mMenuView.findViewById(R.id.fp_report);

        fp_linear_sharetoWeixin = (LinearLayout) mMenuView.findViewById(R.id.fp_linear_sharetoWeixin);

        fp_linear_sharetoquan = (LinearLayout) mMenuView.findViewById(R.id.fp_linear_sharetoquan);

        fp_linear_sharetoQzone = (LinearLayout) mMenuView.findViewById(R.id.fp_linear_sharetoQzone);

        fp_linear_sharetoQQ = (LinearLayout) mMenuView.findViewById(R.id.fp_linear_sharetoQQ);

        fp_cancel = (TextView) mMenuView.findViewById(R.id.fp_cancel);

        //点击取消按钮，关闭popupWindow

        fp_cancel.setOnClickListener(new OnClickListener() {

            @Override

            public void onClick(View v) {

                dismiss();

            }

        });

        fp_hide_pic.setOnClickListener(itemsOnClick);

        fp_hide_all.setOnClickListener(itemsOnClick);

        fp_report.setOnClickListener(itemsOnClick);

        fp_linear_sharetoWeixin.setOnClickListener(itemsOnClick);

        fp_linear_sharetoquan.setOnClickListener(itemsOnClick);

        fp_linear_sharetoQzone.setOnClickListener(itemsOnClick);

        fp_linear_sharetoQQ.setOnClickListener(itemsOnClick);

        this.setContentView(mMenuView);

        this.setWidth(LayoutParams.MATCH_PARENT);

        this.setHeight(LayoutParams.WRAP_CONTENT);

        ColorDrawable dw = new ColorDrawable(0x000000);

        this.setBackgroundDrawable(dw);

        this.setFocusable(true);
　　　　
        //点击popupWindow之外的部分  关闭popupWindow

        mMenuView.setOnTouchListener(new OnTouchListener() {

            public boolean onTouch(View v, MotionEvent event) {

                int height = mMenuView.findViewById(R.id.fp_linear_share).getTop();

                int y = (int) event.getY();

                if (event.getAction() == MotionEvent.ACTION_UP){

                    if(y<height){

                        dismiss();

                    }

                }

                return true;

            }

        });

    }

    // 可自主添加其他功能需求方法

}

public class MainActivity extends Activity implements View.OnClickListener {
    // 自定义PopupWindow
    private SelectPopupWindow feedSelectPopupWindow;
    // 界面父容器
    private RelativeLayout relativeLayout;
    // 打开popupWindow的按钮
    private ImageButton btn_more;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        relativeLayout = (RelativeLayout) findViewById(R.id.mainlayout);
        btn_more = (ImageButton) findViewById(R.id.btn_more);
        btn_more.setOnClickListener(this);
    }

    // popupWindow 点击事件监听
    private View.OnClickListener selectItemsOnClick = new View.OnClickListener() {
        public void onClick(View v) {
            switch (v.getId()) {
                //根据popupWindow 布局文件中的id 来执行相应的点击事件
                case R.id.fp_linear_sharetoWeixin:
                    Toast.makeText(MainActivity.this,"点击了微信分享",Toast.LENGTH_SHORT).show();
                    break;
                // ....
            }
            //每次点击popupWindow中的任意按钮，记得关闭此popupWindow，
            feedSelectPopupWindow.dismiss();
        }
    };

    /**
     * 设置添加屏幕的背景透明度
     * @param bgAlpha
     */
    public void backgroundAlpha(float bgAlpha)
    {
        WindowManager.LayoutParams lp = getWindow().getAttributes();
        lp.alpha = bgAlpha; //0.0-1.0
        getWindow().setAttributes(lp);
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            //点击分享按钮，弹出PopupWindow
            case R.id.btn_more:
                feedSelectPopupWindow = new SelectPopupWindow(this, selectItemsOnClick);
                // 设置popupWindow显示的位置
                // 此时设在界面底部并且水平居中
                feedSelectPopupWindow.showAtLocation(relativeLayout,
                        Gravity.BOTTOM| Gravity.CENTER_HORIZONTAL, 0, 0);
                // 当popupWindow 出现的时候 屏幕的透明度  ，设为0.5 即半透明 灰色效果
                backgroundAlpha(0.5f);
                // 设置popupWindow取消的点击事件，即popupWindow消失后，屏幕的透明度，全透明，就回复原状态
                feedSelectPopupWindow.setOnDismissListener(new PopupWindow.OnDismissListener() {
                    @Override
                    public void onDismiss() {
                        backgroundAlpha(1f);
                    }
                });
                break;
        }
    }
}

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