PopUpWindow的使用

public class MainActivity extends Activity {
	private Button button;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        button = (Button)findViewById(R.id.button);
        button.setOnClickListener(new OnClickListener() {
			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				View view = getLayoutInflater().inflate(R.layout.popupwindow, null);
				PopupWindow popupWindow = new PopupWindow(view,
						LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
				//setBackgroundDrawable必须要有，不然点击window以外区域不会消失
				popupWindow.setBackgroundDrawable(
						getResources().getDrawable(android.R.drawable.btn_plus));
//				popupWindow.setTouchable(true);
//				popupWindow.setOutsideTouchable(true);
				popupWindow.setFocusable(true);
				popupWindow.showAtLocation(v, Gravity.BOTTOM, 0, 0);
			}
		});
    }
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/RelativeLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.popupwindow.MainActivity" >

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:text="@string/click" />

</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
    android:orientation="vertical"
    tools:context=".MainActivity" >

    <Button
        android:id="@+id/button1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@android:string/cancel" />

    <Button
        android:id="@+id/button2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@android:string/ok" />

</LinearLayout>