妳可以看到附件中的截圖，我們將創建壹個列表顯示所有已安裝的應用程序。
snippet_list_row.xml--------------------這個布局是由ListView適配器用於表示應用程序的細節。它顯示應用程序圖標、應用程序名稱和應用程序包。
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="/apk/res/android" android:layout_width="fill_parent" android:layout_height="wrap_content" > <ImageView android:id="@+id/app_icon" android:layout_width="50dp" android:layout_height="50dp" android:padding="3dp" android:scaleType="centerCrop" /> <LinearLayout android:layout_width="fill_parent" android:layout_height="fill_parent" android:gravity="center_vertical" android:orientation="vertical" android:paddingLeft="5dp" > <TextView android:id="@+id/app_name" android:layout_width="fill_parent" android:layout_height="wrap_content" android:gravity="center_vertical" android:textStyle="bold" /> <TextView android:id="@+id/app_paackage" android:layout_width="fill_parent" android:layout_height="wrap_content" android:gravity="center_vertical" /> </LinearLayout></LinearLayout>
AllAppsActivity.java ##這是用於初始化和列表已安裝的應用程序的主要應用程序類。從packagemanage得到應用細節列表是壹個耗時的任務，我們將在AsyncTask裏面做。同時，類使用自定義適配器“自定義listview applicationadapter”。 package com.javatechig.listapps;import java.util.ArrayList;import java.util.List;import android.app.AlertDialog;import android.app.ListActivity;import android.app.ProgressDialog;import android.content.ActivityNotFoundException;import android.content.DialogInterface;import android.content.Intent;import android.content.pm.ApplicationInfo;import android.content.pm.PackageManager;import android.net.Uri;import android.os.AsyncTask;import android.os.Bundle;import android.view.Menu;import android.view.MenuInflater;import android.view.MenuItem;import android.view.View;import android.widget.ListView;import android.widget.Toast;public class AllAppsActivity extends ListActivity { private PackageManager packageManager = null; private List<ApplicationInfo> applist = null; private ApplicationAdapter listadaptor = null; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); packageManager = getPackageManager(); new LoadApplications().execute(); } public boolean onCreateOptionsMenu(Menu menu) { MenuInflater inflater = getMenuInflater(); inflater.inflate(R.menu.menu, menu); return true; } public boolean onOptionsItemSelected(MenuItem item) { boolean result = true; switch (item.getItemId()) { case R.id.menu_about: { displayAboutDialog(); break; } default: { result = super.onOptionsItemSelected(item); break; } } return result; } private void displayAboutDialog() { final AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setTitle(getString(R.string.about_title)); builder.setMessage(getString(R.string.about_desc)); builder.setPositiveButton("Know More", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int id) { Intent browserIntent = new Intent(Intent.ACTION_VIEW, Uri.parse("")); startActivity(browserIntent); dialog.cancel(); } }); builder.setNegativeButton("No Thanks!", new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int id) { dialog.cancel(); } }); builder.show(); } @Override protected void onListItemClick(ListView l, View v, int position, long id) { super.onListItemClick(l, v, position, id); ApplicationInfo app = applist.get(position); try { Intent intent = packageManager .getLaunchIntentForPackage(app.packageName); if (null != intent) { startActivity(intent); } } catch (ActivityNotFoundException e) { Toast.makeText(AllAppsActivity.this, e.getMessage(), Toast.LENGTH_LONG).show(); } catch (Exception e) { Toast.makeText(AllAppsActivity.this, e.getMessage(), Toast.LENGTH_LONG).show(); } } private List<ApplicationInfo> checkForLaunchIntent(List<ApplicationInfo> list) { ArrayList<ApplicationInfo> applist = new ArrayList<ApplicationInfo>(); for (ApplicationInfo info : list) { try { if (null != packageManager.getLaunchIntentForPackage(info.packageName)) { applist.add(info); } } catch (Exception e) { e.printStackTrace(); } } return applist; } private class LoadApplications extends AsyncTask<Void, Void, Void> { private ProgressDialog progress = null; @Override protected Void doInBackground(Void... params) { applist = checkForLaunchIntent(packageManager.getInstalledApplications(PackageManager.GET_META_DATA)); listadaptor = new ApplicationAdapter(AllAppsActivity.this, R.layout.snippet_list_row, applist); return null; } @Override protected void onCancelled() { super.onCancelled(); } @Override protected void onPostExecute(Void result) { setListAdapter(listadaptor); progress.dismiss(); super.onPostExecute(result); } @Override protected void onPreExecute() { progress = ProgressDialog.show(AllAppsActivity.this, null, "Loading application info..."); super.onPreExecute(); } @Override protected void onProgressUpdate(Void... values) { super.onProgressUpdate(values); } }}
package com.javatechig.listapps;import java.util.List;import android.content.Context;import android.content.pm.ApplicationInfo;import android.content.pm.PackageManager;import android.view.LayoutInflater;import android.view.View;import android.view.ViewGroup;import android.widget.ArrayAdapter;import android.widget.ImageView;import android.widget.TextView;public class ApplicationAdapter extends ArrayAdapter<ApplicationInfo> { private List<ApplicationInfo> appsList = null; private Context context; private PackageManager packageManager; public ApplicationAdapter(Context context, int textViewResourceId, List<ApplicationInfo> appsList) { super(context, textViewResourceId, appsList); this.context = context; this.appsList = appsList; packageManager = context.getPackageManager(); } @Override public int getCount() { return ((null != appsList) ? appsList.size() : 0); } @Override public ApplicationInfo getItem(int position) { return ((null != appsList) ? appsList.get(position) : null); } @Override public long getItemId(int position) { return position; } @Override public View getView(int position, View convertView, ViewGroup parent) { View view = convertView; if (null == view) { LayoutInflater layoutInflater = (LayoutInflater) context .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = layoutInflater.inflate(R.layout.snippet_list_row, null); } ApplicationInfo applicationInfo = appsList.get(position); if (null != applicationInfo) { TextView appName = (TextView) view.findViewById(R.id.app_name); TextView packageName = (TextView) view.findViewById(R.id.app_paackage); ImageView iconview = (ImageView) view.findViewById(R.id.app_icon); appName.setText(applicationInfo.loadLabel(packageManager)); packageName.setText(applicationInfo.packageName); iconview.setImageDrawable(applicationInfo.loadIcon(packageManager)); } return view; }};