彈出視窗(PopupWindow)

彈出視窗(PopupWindow)就像是一個浮動在主屏幕之上的視窗.

實例:



修改main.xml, 添加一個按鈕用來打開彈出視窗(PopupWindow).

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello" />
    <Button
        android:id="@+id/openpopupwindow"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Open PopupWindow" />

</LinearLayout>

主要的Java代碼.

package com.PopupWindow;

import android.app.Activity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.PopupWindow;

public class PopupWindowActivity extends Activity {
 
 Button buttonOpen;
 
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        buttonOpen = (Button)findViewById(R.id.openpopupwindow);
        buttonOpen.setOnClickListener(buttonOpenOnClickListener);
    }
    
    Button.OnClickListener buttonOpenOnClickListener
    = new Button.OnClickListener(){

  @Override
  public void onClick(View view) {
   openPopupWindow(view);
  }};
  
 private void openPopupWindow(View v){
  LayoutInflater layoutInflater = (LayoutInflater)getBaseContext()
    .getSystemService(LAYOUT_INFLATER_SERVICE);
  View popupView = layoutInflater.inflate(R.layout.popup, null);
  final PopupWindow popupWindow = new PopupWindow(popupView,
    LayoutParams.WRAP_CONTENT, 
    LayoutParams.WRAP_CONTENT);
  Button buttonClose = (Button)popupView.findViewById(R.id.closepopupwindow);
  buttonClose.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View v) {
    // TODO Auto-generated method stub
    popupWindow.dismiss();
   }});

  popupWindow.showAsDropDown(buttonOpen);
  popupWindow.setFocusable(true);
  popupWindow.update();
 }
}

創建/res/layout/popup.xml文件, 定義彈出視窗的佈局.

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:background="#000055">
      <TextView
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="PopupWindow" />
      <Button
          android:id="@+id/closepopupwindow"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:text="OK" />
</LinearLayout>