Android 弹出菜单PopupWindow

利用继承PopupWindow，自定义类实现弹出菜单并为弹出菜单添加动画效果。

自定义PopupMenu继承PopupWindow：

import android.app.Activity;
import android.content.Context;
import android.graphics.drawable.ColorDrawable;
import android.view.Display;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.LinearLayout.LayoutParams;
import android.widget.PopupWindow;
import android.widget.TextView;

public class PopupMenu extends PopupWindow implements OnClickListener {

	private Activity activity;
	private View popView;

	private int mWidth;
	private int mHeight;

	private View v_item1;
	private View v_item2;
	private View v_item3;

	private OnItemClickListener onItemClickListener;

	/**
	 *
	 * 枚举，选择选项标识
	 */
	public enum MENUITEM {
		ITEM1, ITEM2, ITEM3
	}

	private String[]  tabs;

	public PopupMenu(Activity activity ,String[] tabs) {
		super(activity);
		this.activity = activity;
		this.tabs = tabs;
		Display display = activity.getWindowManager().getDefaultDisplay();
		mWidth = display.getWidth();
		mHeight = display.getHeight();
		LayoutInflater inflater = (LayoutInflater) activity
				.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
		popView = inflater.inflate(R.layout.popup_menu, null);// 加载菜单布局文件
		this.setContentView(popView);// 把布局文件添加到popupwindow中
		this.setWidth(mWidth*4/5);// 设置菜单的宽度（需要和菜单于右边距的距离搭配，可以自己调到合适的位置）
		this.setHeight(LayoutParams.MATCH_PARENT);
		this.setFocusable(true);// 获取焦点
		this.setTouchable(true); // 设置PopupWindow可触摸
		this.setOutsideTouchable(true); // 设置非PopupWindow区域可触摸
		this.setAnimationStyle(R.style.popupAnimation);
		ColorDrawable dw = new ColorDrawable(0x00000000);
		this.setBackgroundDrawable(dw);

		// 获取选项卡
		v_item1 = popView.findViewById(R.id.ly_item1);
		v_item2 = popView.findViewById(R.id.ly_item2);
		v_item3 = popView.findViewById(R.id.ly_item3);
		// 添加监听
		v_item1.setOnClickListener(this);
		v_item2.setOnClickListener(this);
		v_item3.setOnClickListener(this);

	}


	/**
	 * 设置显示的位置
	 *
	 * @param resourId
	 *            这里的x,y值自己调整可以
	 */
	public void showLocation(int resourId) {
		showAsDropDown(activity.findViewById(resourId), dip2px(activity, 0),
				dip2px(activity, -8));
	}

	@Override
	public void onClick(View v) {
		MENUITEM menuitem = null;
		String str = "";
		if (v == v_item1) {
			menuitem = MENUITEM.ITEM1;
			str = tabs[0];
			TextView tvAboutUs = (TextView)v_item1.findViewById(R.id.tv_about_us);
			tvAboutUs.setText(str);
		} else if (v == v_item2) {
			menuitem = MENUITEM.ITEM2;
			str = tabs[1];
			TextView tvAboutUs = (TextView)v_item2.findViewById(R.id.tv_check_update);
			tvAboutUs.setText(str);
		} else if (v == v_item3) {
			menuitem = MENUITEM.ITEM3;
			str = tabs[2];
			TextView tvAboutUs = (TextView)v_item3.findViewById(R.id.tv_feedback);
			tvAboutUs.setText(str);
		}
		if (onItemClickListener != null) {
			onItemClickListener.onClick(menuitem, str);
		}
		dismiss();
	}

	// dip转换为px
	public int dip2px(Context context, float dipValue) {
		final float scale = context.getResources().getDisplayMetrics().density;
		return (int) (dipValue * scale + 0.5f);
	}

	// 点击监听接口
	public interface OnItemClickListener {
		void onClick(MENUITEM item, String str);
	}

	// 设置监听
	public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
		this.onItemClickListener = onItemClickListener;
	}

}

布局文件：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="100dp"
    android:layout_height="wrap_content"
    android:gravity="center_horizontal"
    android:background="#33000000"
    android:orientation="vertical"
    android:layout_gravity="center">
    <LinearLayout
        android:id="@+id/ly_item1"
        android:layout_width="match_parent"
        android:layout_height="45dip"
        android:gravity="center_vertical"
        android:orientation="horizontal"
        android:background="@drawable/bg_default_button_selector">

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="15sp"
            android:paddingLeft="20dip"
            android:id="@+id/tv_about_us"
            android:textColor="#595d5f"
            android:text="选项一" />

    </LinearLayout>
    <View
        android:layout_width="match_parent"
        android:layout_height="1dip"
        android:background="#eeeeee" />
    <LinearLayout
        android:id="@+id/ly_item2"
        android:layout_width="match_parent"
        android:layout_height="45dip"
        android:gravity="center_vertical"
        android:orientation="horizontal"
        android:background="@drawable/bg_default_button_selector">

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:paddingLeft="20dip"
            android:paddingRight="20dip"
            android:visibility="gone" />

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="15sp"
            android:paddingLeft="20dip"
            android:textColor="#595d5f"
            android:id="@+id/tv_check_update"
            android:text="选项二" />
    </LinearLayout>
    <View
        android:layout_width="match_parent"
        android:layout_height="1dip"
        android:background="#eeeeee" />
    <LinearLayout
        android:id="@+id/ly_item3"
        android:layout_width="match_parent"
        android:layout_height="45dip"
        android:gravity="center_vertical"
        android:orientation="horizontal"
        android:background="@drawable/bg_default_button_selector" >

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:paddingLeft="20dip"
            android:paddingRight="20dip"
            android:visibility="gone" />

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:textSize="15sp"
            android:paddingLeft="20dip"
            android:textColor="#595d5f"
            android:id="@+id/tv_feedback"
            android:text="选项三" />
    </LinearLayout>

</LinearLayout>

anim文件夹中定义动画文件：

in.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <translate
        android:duration="500"
        android:fromXDelta="-100%"
        android:toXDelta="0" />
    <alpha
        android:duration="500"
        android:fromAlpha="0.0"
        android:toAlpha="1.0" />
</set>

out.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <translate
        android:duration="500"
        android:fromXDelta="0"
        android:toXDelta="-100%" />
    <alpha
        android:duration="500"
        android:fromAlpha="1.0"
        android:toAlpha="0.0" />
</set>

定义style：

<style name="popupAnimation" parent="android:Animation">
    <item name="android:windowEnterAnimation">@anim/in</item>
    <item name="android:windowExitAnimation">@anim/out</item>
</style>

通过setAnimationStyle方法设置popupAnimation实现动画效果。

调用方式：通过showAtLocation设置弹出菜单弹出的位置，实现setOnItemClickListener监听点击选项回调事件。