查詢&開啟應用程式列表 - getInstalledApplications & getLaunchIntentForPackage (一)

因為是教學範例, 所以用GridView抓個預設的android.R.layout.simple_list_item_1←欄位樣式來放我們所需的資料

./res/layout/allap.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello" />

    <GridView
        android:id="@+id/gridView1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:numColumns="2" >
    </GridView>

</LinearLayout>

./src/com.tsots.allap/Activity_ALLAP.java

package com.tsots.allap;

import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.GridView;
import android.widget.Toast;

public class Activity_ALLAP extends Activity {
    Context context = Activity_ALLAP.this;
    GridView gridView1;
    PackageManager packageManager;
    List<ApplicationInfo> allappInfo;
    ArrayList<String> list_apPag = new ArrayList<String>();
    ArrayList<String> list_apName = new ArrayList<String>();
    ArrayAdapter<String> adapter;
    AdapterView.OnItemClickListener mClickListener;
   
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.layout_allap);
       
        gridView1 = (GridView) findViewById (R.id.gridView1);
        packageManager =context.getPackageManager();
        //取得Device中包括系統預設與手動安裝的所有AP
        allappInfo = packageManager.getInstalledApplications(PackageManager.GET_ACTIVITIES);
        queryAPInfo();            

        adapter = new ArrayAdapter<String>(context, android.R.layout.simple_list_item_1, list_apName);
        gridView1.setAdapter(adapter);       
        clickAction();      
        gridView1.setOnItemClickListener(mClickListener);
    }
   
    public ArrayList<String> queryAPInfo()
    {
        for(int i = 0 ; i <allappInfo.size() ; i ++)
        {                
            ApplicationInfo appPI = allappInfo.get(i);//ApplicationInfo{2ad3d2e0 com.android.launcher}
            String apPag = appPI.packageName;         //com.android.launcher
            list_apPag.add(apPag);
            String apName = appPI.loadLabel(packageManager).toString();//Launcher
            list_apName.add(apName);    
        }
        return list_apName;
    }
   
    /*
     *  intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
     *  有此行程式可將不同的activity看成好像是同一個應用程式
     *  當你從主activity跳至另一個activity(此activity早己存在於系統之中)
     *  當你按下"back"後它會跳回主activity
     *  如果沒加入此程式當按下"back"後它則會離開主activity       
     */
    public void clickAction()
    {
        mClickListener = new AdapterView.OnItemClickListener ()
        {
            public void onItemClick(AdapterView parent, View v, int position, long id)
            {
                Intent intent = getPackageManager().getLaunchIntentForPackage(list_apPag.get(position));
                try
                {
                    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                    startActivity(intent);
                }
                catch(NullPointerException e)
                {
                    Toast.makeText(context, "NO Activity can be launch", Toast.LENGTH_LONG).show();
                }
                catch(Exception e)
                {
                    String errorInfo = e.toString();
                    Toast.makeText(context, errorInfo, Toast.LENGTH_LONG).show();
                }
            }
        };
    }
}

%%%%%%%%%%%%%%%%%延伸學習%%%%%%%%%%%%%%%%%%%%%%%%%

package的ACTION_PACKAGE_ADDED / ACTION_PACKAGE_REMOVED事件
http://bedingfield-tsots.blogspot.com/2012/05/broadcastreceiver.html 

 

查詢&開啟應用程式列表 - getInstalledApplications & getLaunchIntentForPackage (二)
http://bedingfield-tsots.blogspot.com/2012/03/getinstalledapplications.html