PopupWindow的简单运用

PopupWindow可实现弹出窗口效果。

PopupWindow与Dialog的区别是：

1.PopupWindow是阻塞式的，Dialog是非阻塞式的。

2.PopupWindow弹出时没有背景，Dialog弹出时有背景。

 

下面是一个简单的例子。

activity类：

package com.zzj.ui.popupwindow;

import android.app.Activity;
import android.graphics.drawable.ColorDrawable;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.PopupWindow;
import android.widget.TextView;
import android.widget.Toast;

import com.zzj.ui.R;

public class PopubWindowActivity extends Activity {

    private PopupWindow popupWindow;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.popupwindow_activity);
        initPopupwindow();
    }

    private void initPopupwindow() {
        LayoutInflater inflater = LayoutInflater.from(this);
        View popupwindowView = inflater
                .inflate(R.layout.popupwindow_menu, null);
        ListView listView = (ListView) popupwindowView
                .findViewById(R.id.listView1);
        listView.setAdapter(new ArrayAdapter<String>(this,
                R.layout.popupwindow_menu_item,
                new String[] { "复制", "修改", "删除" }));
        listView.setOnItemClickListener(new OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) {
                Toast.makeText(PopubWindowActivity.this,
                        ((TextView) view).getText(), Toast.LENGTH_LONG).show();
            }
        });

        popupWindow = new PopupWindow();
        popupWindow.setContentView(popupwindowView);
        popupWindow.setFocusable(true);// 很重要
        ColorDrawable background = new ColorDrawable(0x000000);
        popupWindow.setBackgroundDrawable(background);// 很重要
        popupWindow.setAnimationStyle(R.style.PopupwindowAnimation);// 弹出动画
        popupWindow.setWidth(100);
        popupWindow.setHeight(100);
    }

    public void popupwindow(View v) {
        if (!popupWindow.isShowing()) {
            popupWindow.showAsDropDown(v, 5, 5);
        }
    }
}

有两个非常重要的两个属性focusable和background需要设置。如果popupwindow没有得到焦点，则任何在popupwindow上的点击事件都无效。如果没有给popupwindow设置背景，当popupwindow获取焦点后，back键将无效，并且点击popupwindow之外的范围也无效；如果给popupwindow设置了背景，点击back键或者点击popupwindow之外的范围，popupwindow都将关闭。

 

activity布局文件：

<?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:orientation="vertical" >

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="popupwindow"
        android:text="popupwindow" />

    <Button
        android:id="@+id/button2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="点得到我吗" />

</LinearLayout>

popupwindow布局文件：

<?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="@color/black"
    android:orientation="vertical" >

    <ListView
        android:id="@+id/listView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >
    </ListView>

</LinearLayout>

列表项（菜单项）布局文件：

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:textColor="@color/white" >

</TextView>

样式：

<!-- popupwindow弹出动画 -->
    <style name="PopupwindowAnimation">
        <item name="android:windowEnterAnimation">@anim/fade_in</item>
        <item name="android:windowExitAnimation">@anim/fade_out</item>
    </style>

anim/fade_in动画：

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

    <scale
        android:duration="500"
        android:fromXScale="0.0"
        android:fromYScale="0.0"
        android:toXScale="1.0"
        android:toYScale="1.0" />

</set>

anim/fade_out动画：

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

    <scale
        android:duration="500"
        android:fromXScale="1.0"
        android:fromYScale="1.0"
        android:toXScale="0.0"
        android:toYScale="0.0" />

</set>

效果：