使用Android和XML构建动态用户界面

/* * XmlGui application. * Written by Frank Ableson for IBM Developerworks * June 2010 * Use the code as you wish -- no warranty of fitness, etc, etc. */ package com.msi.ibm; import android.app.Activity; import android.app.AlertDialog; import android.os.Bundle; import android.content.Intent; import android.util.Log; import java.net.URL; import java.net.URLConnection; import java.io.InputStream; import java.io.BufferedReader; import java.io.InputStreamReader; import java.io.BufferedOutputStream; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import android.app.AlertDialog.*; import java.util.ListIterator; import java.lang.Thread; import android.view.View; import android.view.ViewGroup; import android.widget.ScrollView; import android.widget.LinearLayout; import android.widget.Button; import android.widget.LinearLayout.LayoutParams; import android.app.ProgressDialog; import android.os.Handler; import android.os.Message; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.w3c.dom.NamedNodeMap; public class RunForm extends Activity { /** Called when the activity is first created. */ String tag = RunForm.class.getName(); XmlGuiForm theForm; ProgressDialog progressDialog; Handler progressHandler; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); String formNumber = ""; Intent startingIntent = getIntent(); if(startingIntent == null) { Log.e(tag,"No Intent? We're not supposed to be here..."); finish(); return; } formNumber = startingIntent.getStringExtra("formNumber"); Log.i(tag,"Running Form [" + formNumber + "]"); if (GetFormData(formNumber)) { DisplayForm(); } else { Log.e(tag,"Couldn't parse the Form."); AlertDialog.Builder bd = new AlertDialog.Builder(this); AlertDialog ad = bd.create(); ad.setTitle("Error"); ad.setMessage("Could not parse the Form data"); ad.show(); } } private boolean DisplayForm() { try { ScrollView sv = new ScrollView(this); final LinearLayout ll = new LinearLayout(this); sv.addView(ll); ll.setOrientation(android.widget.LinearLayout.VERTICAL); // walk thru our form elements and dynamically create them, leveraging our mini library of tools. int i; for (i=0;i<theForm.fields.size();i++) { if (theForm.fields.elementAt(i).getType().equals("text")) { theForm.fields.elementAt(i).obj = new XmlGuiEditBox(this,(theForm.fields.elementAt(i).isRequired() ? "*" : "") + theForm.fields.elementAt(i).getLabel(),""); ll.addView((View) theForm.fields.elementAt(i).obj); } if (theForm.fields.elementAt(i).getType().equals("numeric")) { theForm.fields.elementAt(i).obj = new XmlGuiEditBox(this,(theForm.fields.elementAt(i).isRequired() ? "*" : "") + theForm.fields.elementAt(i).getLabel(),""); ((XmlGuiEditBox)theForm.fields.elementAt(i).obj).makeNumeric(); ll.addView((View) theForm.fields.elementAt(i).obj); } if (theForm.fields.elementAt(i).getType().equals("choice")) { theForm.fields.elementAt(i).obj = new XmlGuiPickOne(this,(theForm.fields.elementAt(i).isRequired() ? "*" : "") + theForm.fields.elementAt(i).getLabel(),theForm.fields.elementAt(i).getOptions()); ll.addView((View) theForm.fields.elementAt(i).obj); } } Button btn = new Button(this); btn.setLayoutParams(new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,ViewGroup.LayoutParams.WRAP_CONTENT)); ll.addView(btn); btn.setText("Submit"); btn.setOnClickListener(new Button.OnClickListener() { public void onClick(View v) { // check if this form is Valid if (!CheckForm()) { AlertDialog.Builder bd = new AlertDialog.Builder(ll.getContext()); AlertDialog ad = bd.create(); ad.setTitle("Error"); ad.setMessage("Please enter all required (*) fields"); ad.show(); return; } if (theForm.getSubmitTo().equals("loopback")) { // just display the results to the screen String formResults = theForm.getFormattedResults(); Log.i(tag,formResults); AlertDialog.Builder bd = new AlertDialog.Builder(ll.getContext()); AlertDialog ad = bd.create(); ad.setTitle("Results"); ad.setMessage(formResults); ad.show(); return; } else { if (!SubmitForm()) { AlertDialog.Builder bd = new AlertDialog.Builder(ll.getContext()); AlertDialog ad = bd.create(); ad.setTitle("Error"); ad.setMessage("Error submitting form"); ad.show(); return; } } } } ); setContentView(sv); setTitle(theForm.getFormName()); return true; } catch (Exception e) { Log.e(tag,"Error Displaying Form"); return false; } } private boolean SubmitForm() { try { boolean ok = true; this.progressDialog = ProgressDialog.show(this, theForm.getFormName(), "Saving Form Data", true,false); this.progressHandler = new Handler() { @Override public void handleMessage(Message msg) { // process incoming messages here switch (msg.what) { case 0: // update progress bar progressDialog.setMessage("" + (String) msg.obj); break; case 1: progressDialog.cancel(); finish(); break; case 2: progressDialog.cancel(); break; } super.handleMessage(msg); } }; Thread workthread = new Thread(new TransmitFormData(theForm)); workthread.start(); return ok; } catch (Exception e) { Log.e(tag,"Error in SubmitForm()::" + e.getMessage()); e.printStackTrace(); // tell user we failed.... Message msg = new Message(); msg.what = 1; this.progressHandler.sendMessage(msg); return false; } } private boolean CheckForm() { try { int i; boolean good = true; for (i=0;i<theForm.fields.size();i++) { String fieldValue = (String) theForm.fields.elementAt(i).getData(); Log.i(tag,theForm.fields.elementAt(i).getName() + " is [" + fieldValue + "]"); if (theForm.fields.elementAt(i).isRequired()) { if (fieldValue == null) { good = false; } else { if (fieldValue.trim().length() == 0) { good = false; } } } } return good; } catch(Exception e) { Log.e(tag,"Error in CheckForm()::" + e.getMessage()); e.printStackTrace(); return false; } } private boolean GetFormData(String formNumber) { try { Log.i(tag,"ProcessForm"); URL url = new URL("http://servername/xmlgui" + formNumber + ".xml"); Log.i(tag,url.toString()); InputStream is = url.openConnection().getInputStream(); DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); DocumentBuilder db = factory.newDocumentBuilder(); Document dom = db.parse(is); Element root = dom.getDocumentElement(); NodeList forms = root.getElementsByTagName("form"); if (forms.