【Android进阶学习】Popupwindow的应用
PopupWindow 是一种阻塞式的弹出窗口，这就意味着在我们退出这个弹出框之前，程序会一直等待。它可以浮动在当前Activity的任何的位置上。 需要注意的是，PopupWindow必须触发某个焦点或者某个事件才会显示出来，不然总会会出现错误。 下面是使用PopupWindow 弹出自定义菜单的例子 当我们点击Menu键的时候，会在当前的Activity最下方弹出一个菜单。 效果图如下： PopupMenuDemo.java packagecom.lingdududu.popupWindow; importandroid.app.Activity; importandroid.content.Context; importandroid.graphics.drawable.BitmapDrawable; importandroid.os.Bundle; importandroid.view.Gravity; importandroid.view.KeyEvent; importandroid.view.LayoutInflater; importandroid.view.Menu; importandroid.view.MenuItem; importandroid.view.View; importandroid.view.ViewGroup; importandroid.widget.BaseAdapter; importandroid.widget.GridView; importandroid.widget.ImageView; importandroid.widget.LinearLayout; importandroid.widget.PopupWindow; importandroid.widget.TextView; importandroid.widget.LinearLayout.LayoutParams; publicclassPopupMenuDemoextendsActivity{ privateint[]resArray=newint[]{ R.drawable.icon_menu_addto,R.drawable.icon_menu_audioinfo, R.drawable.icon_menu_findlrc,R.drawable.icon_menu_scan }; privateString[]title=newString[]{ "添加","信息","搜索","查看" }; privatePopupWindowpw=null; /**Calledwhentheactivityisfirstcreated.*/ @Override publicvoidonCreate(BundlesavedInstanceState){ super.onCreate(savedInstanceState); setContentView(R.layout.main); } @Override publicbooleanonCreateOptionsMenu(Menumenu){ menu.add(""); returnsuper.onCreateOptionsMenu(menu); } /** *在此方法中实现自定义菜单栏 */ publicbooleanonMenuOpened(intfeatureId,Menumenu){ if(pw!=null){ if(pw.isShowing()){ //就关闭弹出窗口 pw.dismiss(); } else{ //在指定位置弹出窗口 pw.showAtLocation(findViewById(R.id.tv),Gravity.CENTER,0,300); } } else{ LayoutInflaterinflater=(LayoutInflater)this.getSystemService(Context.LAYOUT_INFLATER_SERVICE); Viewview=inflater.inflate(R.layout.menu,null); GridViewgrid1=(GridView)view.findViewById(R.id.menuGridChange); grid1.setAdapter(newImageAdapter(this)); //生成PopupWindow对象 pw=newPopupWindow(view,LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT); //在指定位置弹出窗口 pw.showAtLocation(findViewById(R.id.tv),Gravity.CENTER,0,300); } //此处返回false，系统不会执行onCreateOptionsMenu中添加的菜单 returnfalse; } publicbooleanonKeyDown(intkeyCode,KeyEventevent){ if(keyCode==KeyEvent.KEYCODE_BACK){ pw.dismiss(); returnfalse; } returnsuper.onKeyDown(keyCode,event); } @Override publicbooleanonOptionsItemSelected(MenuItemitem){ returnsuper.onOptionsItemSelected(item); } publicclassImageAdapterextendsBaseAdapter{ privateContextcontext; publicImageAdapter(Contextcontext){ this.context=context; } @Override publicintgetCount(){ returnresArray.length; } @Override publicObjectgetItem(intarg0){ returnresArray[arg0]; } @Override publiclonggetItemId(intarg0){ returnarg0; } @Override publicViewgetView(intarg0,Viewarg1,ViewGrouparg2){ LinearLayoutlinear=newLinearLayout(context); LinearLayout.LayoutParamsparams=newLayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT); linear.setOrientation(LinearLayout.VERTICAL); ImageViewiv=newImageView(context); iv.setImageBitmap(((BitmapDrawable)context.getResources().getDrawable(resArray[arg0])).getBitmap()); LinearLayout.LayoutParamsparams2=newLayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT); params2.gravity=Gravity.CENTER; linear.addView(iv,params2); TextViewtv=newTextView(context); tv.setText(title[arg0]); LinearLayout.LayoutParamsparams3=newLayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT); params3.gravity=Gravity.CENTER; linear.addView(tv,params3); returnlinear; } } } main.xml <?xmlversion="1.0"encoding="utf-8"?> <LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <TextView android:id="@+id/tv" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/hello" /> </LinearLayout> menu.xml <?xmlversion="1.0"encoding="utf-8"?> <LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent" > <TextView android:id="@+id/tv" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/hello" /> </LinearLayout> menu_bg_frame.xml 这个文件是菜单背景的样式文件，在drawable-hdpi文件下面 <?xmlversion="1.0"encoding="UTF-8"?> <shapeandroid:shape="rectangle"xmlns:android="http://schemas.android.com/apk/res/android"> <solidandroid:color="#b4000000"/> <strokeandroid:width="2.0dip"android:color="#b4ffffff"android:dashWidth="3.0dip"android:dashGap="0.0dip"/> <paddingandroid:left="7.0dip"android:top="7.0dip"android:right="7.0dip"android:bottom="7.0dip"/> <cornersandroid:radius="8.0dip"/> </shape> 本文转自 lingdududu 51CTO博客，原文链接： http://blog.51cto.com/liangruijun/739459
