PopMenu.java

package cn.mutils.app.ui;

import android.app.Activity;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Rect;
import android.graphics.drawable.ColorDrawable;
import android.graphics.drawable.GradientDrawable;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.util.TypedValue;
import android.view.Gravity;
import android.view.View;
import android.view.WindowManager;
import android.widget.FrameLayout;
import android.widget.LinearLayout;
import android.widget.PopupWindow;
import android.widget.ScrollView;

import cn.mutils.app.ui.adapter.PopMenuAdapter;
import cn.mutils.app.ui.core.IStatusBarOwner;
import cn.mutils.app.util.AppUtil;

@SuppressWarnings({"deprecation", "unused"})
public class PopMenu<DATA_ITEM> {

    protected View mAnchor;

    protected PopupWindow mPopupWindow;

    protected PopMenuAdapter<DATA_ITEM> mAdapter;

    protected PopMenuListener mListener;

    protected int mBackgroundRes;

    protected int mPopupX;

    protected int mPopupY;

    public PopMenu(View anchor) {
        Context context = anchor.getContext();
        if (!(context instanceof Activity)) {
            throw new IllegalArgumentException("Context is not Activity");
        }
        int[] anchorLocation = new int[2];
        mAnchor = anchor;
        mAnchor.getLocationOnScreen(anchorLocation);
        mPopupX = anchorLocation[0];
        mPopupY = anchorLocation[1];
    }

    public void setAdapter(PopMenuAdapter<DATA_ITEM> adapter) {
        if (mPopupWindow != null) {
            return;
        }
        if (adapter.getContainer() != null) {
            throw new IllegalArgumentException("I will set container by myslef");
        }
        mAdapter = adapter;
        mAdapter.setPopMenu(this);
    }

    public void setListener(PopMenuListener listener) {
        mListener = listener;
    }

    public void dismiss() {
        if (mPopupWindow != null) {
            mPopupWindow.dismiss();
        }
    }

    public void setBackgroundRes(int backgroundRes) {
        if (mPopupWindow != null) {
            return;
        }
        mBackgroundRes = backgroundRes;
    }

    public void show() {
        if (mPopupWindow != null) {
            return;
        }
        Context context = mAnchor.getContext();
        Resources resources = context.getResources();
        DisplayMetrics metrics = resources.getDisplayMetrics();
        int screenHeight = metrics.heightPixels;
        int padding = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 4, metrics);
        Rect popupArea = new Rect();
        ((Activity) context).getWindow().getDecorView().getWindowVisibleDisplayFrame(popupArea);
        boolean statusBarAtTop = popupArea.top > 1;
        boolean statusBarTranslucent = (context instanceof IStatusBarOwner)
                && ((IStatusBarOwner) context).isStatusBarTranslucent();
        if (statusBarTranslucent) {
            statusBarAtTop = true;// Do not know how to do with this case.
        }
        int popupAreaHeight = popupArea.height();
        int statusBarHeight = screenHeight - popupAreaHeight;
        if (statusBarTranslucent) {
            statusBarHeight = AppUtil.getStatusBarHeight(context);
        }
        int anchorHeight = mAnchor.getHeight();
        int halfPopupAreaHeight = popupAreaHeight >> 1;
        boolean underAnchor = (mPopupY - popupArea.top + (anchorHeight >> 1)) < halfPopupAreaHeight;
        mPopupY = underAnchor ? (mPopupY + anchorHeight + padding) : (mPopupY - padding);
        int contentMaxHeight = underAnchor ? (screenHeight - mPopupY - padding - (statusBarAtTop ? 0 : statusBarHeight))
                : (mPopupY - padding - (statusBarAtTop ? statusBarHeight : 0));
        FrameLayout realContentView = new FrameLayout(context);
        realContentView.setPadding(padding, 0, padding, 0);
        OPopupMenuScroller scroller = new OPopupMenuScroller(context);
        scroller.setVerticalScrollBarEnabled(false);
        if (mBackgroundRes != 0) {
            scroller.setBackgroundResource(mBackgroundRes);
        } else {
            GradientDrawable scrollerDrawable = new GradientDrawable();
            scrollerDrawable.setColor(0xFFF5F5F5);
            scrollerDrawable.setStroke(1, 0xD9D9D9D9);
            scroller.setBackgroundDrawable(scrollerDrawable);
        }
        scroller.setMaxHeight(contentMaxHeight);
        if (!underAnchor) {
            scroller.setOnMeasuredListener(new OnMeasuredListener() {

                @Override
                public void onMeasured(View v, int width, int height) {
                    ((OPopupMenuScroller) v).setOnMeasuredListener(null);
                    mPopupY = mPopupY - height;
                    mPopupWindow.update(mPopupX, mPopupY, WindowManager.LayoutParams.WRAP_CONTENT,
                            WindowManager.LayoutParams.WRAP_CONTENT);
                }
            });
        }
        LinearLayout scrollContent = new LinearLayout(context);
        scrollContent.setOrientation(LinearLayout.VERTICAL);
        if (mAdapter != null) {
            mAdapter.setContainer(scrollContent);
        }
        scroller.addView(scrollContent, new FrameLayout.LayoutParams(FrameLayout.LayoutParams.WRAP_CONTENT,
                FrameLayout.LayoutParams.WRAP_CONTENT));
        realContentView.addView(scroller, new FrameLayout.LayoutParams(FrameLayout.LayoutParams.WRAP_CONTENT,
                FrameLayout.LayoutParams.WRAP_CONTENT));

        mPopupWindow = new PopupWindow(realContentView, WindowManager.LayoutParams.WRAP_CONTENT,
                WindowManager.LayoutParams.WRAP_CONTENT);
        mPopupWindow.setBackgroundDrawable(new ColorDrawable(0x00000000));
        mPopupWindow.setOutsideTouchable(true);
        mPopupWindow.setFocusable(true);
        mPopupWindow.showAtLocation(mAnchor, Gravity.NO_GRAVITY, mPopupX, mPopupY);
        mPopupWindow.setOnDismissListener(new PopupWindow.OnDismissListener() {

            @Override
            public void onDismiss() {
                if (mListener != null) {
                    mListener.onDismiss();
                }
                mPopupWindow = null;
            }
        });
    }

    public static interface PopMenuListener {

        public void onDismiss();

    }

    protected static interface OnMeasuredListener {

        public void onMeasured(View v, int width, int height);

    }

    protected static class OPopupMenuScroller extends ScrollView {

        protected int mMaxHeight;

        protected int mMaxWidth;

        protected OnMeasuredListener mOnMeasuredListener;

        public OPopupMenuScroller(Context context) {
            super(context);
        }

        public OPopupMenuScroller(Context context, AttributeSet attrs) {
            super(context, attrs);
        }

        public OPopupMenuScroller(Context context, AttributeSet attrs, int defStyle) {
            super(context, attrs, defStyle);
        }

        @Override
        protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
            super.onMeasure(widthMeasureSpec, heightMeasureSpec);
            int measuredWidth = this.getMeasuredWidth();
            int measuredHeight = this.getMeasuredHeight();
            boolean measuredChanged = false;
            if (mMaxWidth > 0 && measuredWidth > mMaxWidth) {
                measuredWidth = mMaxWidth;
                measuredChanged = true;
            }
            if (mMaxHeight > 0 && measuredHeight > mMaxHeight) {
                measuredHeight = mMaxHeight;
                measuredChanged = true;
            }
            if (measuredChanged) {
                this.setMeasuredDimension(measuredWidth, measuredHeight);
            }
            if (mOnMeasuredListener != null) {
                mOnMeasuredListener.onMeasured(this, measuredWidth, measuredHeight);
            }
        }

        public int getMaxHeight() {
            return mMaxHeight;
        }

        public void setMaxHeight(int maxHeight) {
            this.mMaxHeight = maxHeight;
        }

        public int getMaxWidth() {
            return mMaxWidth;
        }

        public void setMaxWidth(int maxWidth) {
            this.mMaxWidth = maxWidth;
        }

        public void setOnMeasuredListener(OnMeasuredListener listener) {
            mOnMeasuredListener = listener;
        }

    }

}