Implement own App Launcher

Implement own App Launcher

This example demonstrate how to implement our own App Launcher; list icons of installed App in GridView, and launchth the app once clicked.

Modify layout to XML to use GridView.

<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:numColumns="auto_fit"
    android:verticalSpacing="10dp"
    android:horizontalSpacing="10dp"
    android:columnWidth="50dp"
    android:stretchMode="columnWidth"
    android:gravity="center"/>

Main Code.

package com.example.androidapplauncher;

import java.util.List;

import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.pm.ActivityInfo;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;

public class MainActivity extends Activity {
 
 PackageManager myPackageManager;
 
 public class MyBaseAdapter extends BaseAdapter {
  
  private Context myContext;
  private List<ResolveInfo> MyAppList;

  MyBaseAdapter(Context c, List<ResolveInfo> l){
   myContext = c;
   MyAppList = l;
  }
  
  @Override
  public int getCount() {
   return MyAppList.size();
  }
  
  @Override
  public Object getItem(int position) {
   return MyAppList.get(position);
  }
  
  @Override
  public long getItemId(int position) {
   return position;
  }
  
  @Override
  public View getView(int position, View convertView, ViewGroup parent) {
   
   ImageView imageView;
   if (convertView == null) {
    // if it's not recycled, initialize some attributes
    imageView = new ImageView(myContext);
    imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
    imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
    imageView.setPadding(8, 8, 8, 8); 
   } else {
    imageView = (ImageView)convertView; 
   }
   
   ResolveInfo resolveInfo = MyAppList.get(position);
   imageView.setImageDrawable(resolveInfo.loadIcon(myPackageManager));

   return imageView;
         
  }
  
 }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        myPackageManager = getPackageManager();
        
        Intent intent = new Intent(Intent.ACTION_MAIN, null);
        intent.addCategory(Intent.CATEGORY_LAUNCHER);
        List<ResolveInfo> intentList = getPackageManager().queryIntentActivities(intent, 0);
        
        GridView gridview = (GridView) findViewById(R.id.gridview);
        gridview.setAdapter(new MyBaseAdapter(this, intentList));
        
        gridview.setOnItemClickListener(myOnItemClickListener);
    }
    
    OnItemClickListener myOnItemClickListener =
      new OnItemClickListener(){

    @Override
    public void onItemClick(AdapterView<?> parent, View view,
      int position, long id) {
     ResolveInfo cleckedResolveInfo = 
       (ResolveInfo)parent.getItemAtPosition(position);
     ActivityInfo clickedActivityInfo = 
       cleckedResolveInfo.activityInfo;

     Intent intent = new Intent(Intent.ACTION_MAIN);
        intent.addCategory(Intent.CATEGORY_LAUNCHER);
        intent.setClassName(
          clickedActivityInfo.applicationInfo.packageName,
          clickedActivityInfo.name);
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | 
          Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);
        startActivity(intent);
      
    }

    };
    
}

Download the files.