更新以下适用于API 26，但它在API 23上崩溃。有谁知道为什么会这样？还有，任何解决方法？
我的android开发真的需要你的帮助。我想要做的是拥有PopupWindow。在弹出窗口内，有一个按钮，显示弹出菜单。
这在技术上是否可行？我有以下代码，但当我点击popupwindow中的按钮时它停止工作。该应用程序关闭了“popupMenu.show（）”行
import android.os.Build;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.PopupWindow;
import android.widget.PopupMenu;
import android.widget.RelativeLayout;
public class MainActivity extends AppCompatActivity {
private Button mPopupWindowButton;
private Button mButtonPopupMenuOnPopupWindow;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mPopupWindowButton = (Button) findViewById(R.id.btn);
mPopupWindowButton.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View view) {
LayoutInflater inflater = (LayoutInflater)getApplicationContext().getSystemService(LAYOUT_INFLATER_SERVICE);
View settingsView = inflater.inflate(R.layout.settings, null);
PopupWindow popupWindow = new PopupWindow(settingsView, RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
if(Build.VERSION.SDK_INT >=21){
popupWindow.setElevation(5.0f);
}
LinearLayout mainLayout = (LinearLayout)findViewById(R.id.mainActivityLayout);
popupWindow.showAtLocation(mainLayout, Gravity.BOTTOM,0,0);
mButtonPopupMenuOnPopupWindow = settingsView.findViewById(R.id.btnPopupMenuOnPopupWindow);
mButtonPopupMenuOnPopupWindow.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
PopupMenu popupMenu = new PopupMenu(MainActivity.this, view);
popupMenu.inflate(R.menu.age_group);
popupMenu.show();
}
});
}
});
}
}
如果这是不可能的，是否有解决方法？基本上，我想在popupwindow中有一个下拉选项。
谢谢你的时间。
UPDATE
这是崩溃日志
12-31 21:09:49.600 3960-3960/com.codingdaddy.popupwindowexample E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.codingdaddy.popupwindowexample, PID: 3960
android.view.WindowManager$BadTokenException: Unable to add window -- token android.view.ViewRootImpl$W@4f880f0 is not valid; is your activity running?
at android.view.ViewRootImpl.setView(ViewRootImpl.java:567)
at android.view.WindowManagerGlobal.addView(WindowManagerGlobal.java:310)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:85)
at android.widget.PopupWindow.invokePopup(PopupWindow.java:1258)
at android.widget.PopupWindow.showAsDropDown(PopupWindow.java:1110)
at android.widget.ListPopupWindow.show(ListPopupWindow.java:658)
at com.android.internal.view.menu.MenuPopupHelper.tryShow(MenuPopupHelper.java:170)
at com.android.internal.view.menu.MenuPopupHelper.show(MenuPopupHelper.java:124)
at android.widget.PopupMenu.show(PopupMenu.java:218)
at com.codingdaddy.popupwindowexample.MainActivity$1$1.onClick(MainActivity.java:50)
at android.view.View.performClick(View.java:5198)
at android.view.View$PerformClick.run(View.java:21147)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
是的，有可能请修改您的以下点击监听器，如下所示： - 而不是getBaseContext使用Activity.this
mButtonPopupMenuOnPopupWindow = settingsView.findViewById(R.id.btnPopupMenuOnPopupWindow);
mButtonPopupMenuOnPopupWindow.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
PopupMenu popupMenu = new PopupMenu(MainActivity.this, view);
popupMenu.inflate(R.menu.menu);
popupMenu.show();
}
});
主要布局文件
<LinearLayout android:id="@+id/main_layout"
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:gravity="center_horizontal"
android:orientation="vertical"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="lib4.com.stackoverflow.SimpleActivity">
<Button android:id="@+id/btn" android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TAP"/>
</LinearLayout>
设置布局文件
<LinearLayout android:id="@+id/main_layout"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_horizontal"
android:orientation="vertical"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin">
<Button android:id="@+id/btnPopupMenuOnPopupWindow" android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="button"/>
</LinearLayout>
菜单资源文件
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@+id/about"
android:title="About"/>
<item android:id="@+id/help"
android:title="Help"/>
</menu>
如果有效，请告诉我。