Android列出所有应用，点击可运行~

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends Activity {

    List<AppsItemInfo> list;

    private GridView gridview;
    private PackageManager pManager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        this.setContentView(R.layout.activity_main);

        gridview = (GridView) findViewById(R.id.gridview);

        pManager = MainActivity.this.getPackageManager();
        List<PackageInfo> appList = getAllApps(MainActivity.this);

        list = new ArrayList<AppsItemInfo>();

        for (int i = 0; i < appList.size(); i++) {
            PackageInfo pinfo = appList.get(i);
            AppsItemInfo shareItem = new AppsItemInfo();
            shareItem.setIcon(pManager.getApplicationIcon(pinfo.applicationInfo));
            shareItem.setLabel(pManager.getApplicationLabel(
                    pinfo.applicationInfo).toString());
            shareItem.setPackageName(pinfo.applicationInfo.packageName);

            list.add(shareItem);

        }

        gridview.setAdapter(new baseAdapter());

        gridview.setOnItemClickListener(new ClickListener());

    }

    public static List<PackageInfo> getAllApps(Context context) {

        List<PackageInfo> apps = new ArrayList<PackageInfo>();
        PackageManager pManager = context.getPackageManager();
        List<PackageInfo> packlist = pManager.getInstalledPackages(0);
        for (int i = 0; i < packlist.size(); i++) {
            PackageInfo pak = (PackageInfo) packlist.get(i);
            if ((pak.applicationInfo.flags & pak.applicationInfo.FLAG_SYSTEM) <= 0) {
                apps.add(pak);
            }
        }
        return apps;
    }

    private class baseAdapter extends BaseAdapter {
        LayoutInflater inflater = LayoutInflater.from(MainActivity.this);
        @Override
        public int getCount() {return list.size();}
        @Override
        public Object getItem(int position) {return null;}
        @Override
        public long getItemId(int position) {return position;}
        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ViewHolder holder;
            if (convertView == null) {
                convertView = inflater.inflate(R.layout.apps, null);
                holder = new ViewHolder();
                holder.icon = (ImageView) convertView
                        .findViewById(R.id.apps_image);
                holder.label = (TextView) convertView
                        .findViewById(R.id.apps_textview);
                convertView.setTag(holder);
            } else {
                holder = (ViewHolder) convertView.getTag();
            }
            holder.icon.setImageDrawable(list.get(position).getIcon());
            holder.label.setText(list.get(position).getLabel().toString());
            return convertView;
        }
    }

    private class ViewHolder{
        private ImageView icon;
        private TextView label;
    }

    private class ClickListener implements AdapterView.OnItemClickListener {

        @Override
        public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,long arg3) {
            Intent intent = new Intent();
            intent = MainActivity.this.getPackageManager().getLaunchIntentForPackage(list.get(arg2).getPackageName());
            startActivity(intent);
        }
    }

    private class AppsItemInfo {

        private Drawable icon;
        private String label;
        private String packageName;

        public Drawable getIcon() {
            return icon;
        }

        public void setIcon(Drawable icon) {
            this.icon = icon;
        }

        public String getLabel() {
            return label;
        }

        public void setLabel(String label) {
            this.label = label;
        }

        public String getPackageName() {
            return packageName;
        }

        public void setPackageName(String packageName) {
            this.packageName = packageName;
        }
    }
}

<?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">

    <GridView xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/gridview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:columnWidth="95dp"
        android:gravity="center"
        android:horizontalSpacing="12dp"
        android:numColumns="auto_fit"
        android:stretchMode="columnWidth"
        android:verticalSpacing="15dp" />
</LinearLayout>  

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

    <ImageView
        android:id="@+id/apps_image"
        android:layout_width="48dip"
        android:layout_height="48dip"
        android:icon="@mipmap/ic_launcher" />

    <TextView
        android:id="@+id/apps_textview"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:maxLines="1"
        android:maxEms="5"
        android:text="good" />

</LinearLayout>