转于：http://my.oschina.net/xsjayz/blog/184848#OSC_h2_5
----------------------------------------------------------------------------------------------------
一、概述
1、构造方法
部分常用：
|
1
2
3
4
|
PopupWindow(View contentView,
int
width,
int
height)
Create a
new
non focusable popup window which can display the contentView.
PopupWindow(View contentView,
int
width,
int
height,
boolean
focusable)
Create a
new
popup window which can display the contentView.
|
contentView为要显示的view，width和height为宽和高，值为像素值，也可以是MATCHT_PARENT和WRAP_CONTENT。
focusable为是否可以获得焦点，也可以通过set方法设置：
|
1
2
|
// Changes the focusability of the popup window
setFocusable(
boolean
focusable)
|
根据网上的资料，focusable参数的主要作用是：
如果focusable为false，在一个Activity弹出一个PopupWindow，按返回键，由于PopupWindow没有焦点，会直接退出Activity。如果focusable为true，PopupWindow弹出后，所有的触屏和物理按键都由PopupWindow处理。
如果PopupWindow中有Editor的话，focusable要为true。
二、初始化PopupWindow
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
|
/**
* 初始化rightPopupWindow
*/
private
PopupWindow initPopupWindow() {
LayoutInflater inflater = LayoutInflater.from(
this
);
View popView = inflater.inflate(R.layout.popupwindow_content,
null
);
TextView item = (TextView) popView.findViewById(R.id.text_item);
// 创建PopupWindow
final
PopupWindow popupWindow = createPopupWindow(popView);
popView.setOnTouchListener(
new
View.OnTouchListener() {
@Override
public
boolean
onTouch(View v, MotionEvent event) {
if
(rightPop !=
null
&& rightPop.isShowing()) {
popupWindow.dismiss();
}
return
true
;
}
});
item.setOnClickListener(
new
View.OnClickListener() {
@Override
public
void
onClick(View v) {
popupWindow.dismiss();
// ...
}
});
return
popupWindow;
}
|
三、创建一个PopupWindow
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
|
/**
* 创建PopupWindow
*
* @param popView
* 指定PopupWindow的内容
*/
private
PopupWindow createPopupWindow(View popView) {
PopupWindow popupInstance =
new
PopupWindow(popView, LayoutParams.MATCH_PARENT,
LayoutParams.MATCH_PARENT);
popupInstance.setFocusable(
true
);
popupInstance.setBackgroundDrawable(
new
ColorDrawable(
0
));
popupInstance.setOutsideTouchable(
true
);
// 监听器
popupInstance.setOnDismissListener(
new
PopupWindow.OnDismissListener() {
@Override
public
void
onDismiss() {
// ...
}
});
return
popupInstance;
}
|
四、显示
例如一个button，点击该按钮，显示popupWindow，并且要求popupWindow显示在该按钮下面，则
|
1
2
3
4
5
6
7
|
btn.setOnClickListener(
new
View.OnClickListener() {
@Override
public
void
onClick(View v) {
PopupWindow popupWindow = ...;
popupWindow.showAsDropDown(v);
}
});
|
另外，还支持指定位+置偏移量显示：
|
1
|
public
void
showAsDropDown(View anchor,
int
xoff,
int
yoff);
|
|
1
2
3
4
5
6
7
8
9
|
public
void
showAtLocation (View parent,
int
gravity,
int
x,
int
y)
Display the content view in a popup window at the specified location. If the popup window cannot fit on screen, it will be clipped. See WindowManager.LayoutParams
for
more information on how gravity and the x and y parameters are related. Specifying a gravity of NO_GRAVITY is similar to specifying Gravity.LEFT | Gravity.TOP.
Parameters
parent a parent view to get the getWindowToken() token from
gravity the gravity which controls the placement of the popup window
x the popup's x location offset
y the popup's y location offset
|
五、popupWindow显示优化
1、动画效果
例如显示的时候，从底部出现或者从顶部出现等，可以添加自定义动画效果。
|
1
2
3
4
5
6
7
8
9
|
<?
xml
version
=
"1.0"
encoding
=
"utf-8"
?>
<
set
xmlns:android
=
"http://schemas.android.com/apk/res/android"
>
<
translate
android:duration
=
"250"
android:fromYDelta
=
"100.0%"
android:toYDelta
=
"0.0"
/>
</
set
>
|
|
1
2
3
4
5
6
7
8
9
|
<?
xml
version
=
"1.0"
encoding
=
"utf-8"
?>
<
set
xmlns:android
=
"http://schemas.android.com/apk/res/android"
>
<
translate
android:duration
=
"250"
android:fromYDelta
=
"0.0"
android:toYDelta
=
"100%"
/>
</
set
>
|
2、其他效果
默认的popupWindow显示的时候，是没有像Dialog那样的背景变成灰色半透明效果的。可以自己添加类似Dialog或ios那样的效果。
例如，设置popupWindow的显示内容的布局文件的background属性为灰色半透明颜色，然后popupWindow在创建的时候指定宽、高属性为MATCH_PARENT即可实现除了popupWindow以外区域变成灰色半透明效果。
当然，这个灰色区域，其实也属于popupWindow，只是没有真正的内容。这时候如果需要设置点击popupWindow以外区域让它自动消失的话，就需要额外处理。因为点击灰色部分，你仍然点击的是popupWindow本身。
一种方法是给popupWindow的整个布局区域添加onTouch事件监听器，手动让popupWindow去dismiss()掉。