自定义Lancher

效果图

运行程序得到的效果图

布局文件

activity_main.xml主布局文件

<RelativeLayoutxmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:background="@color/brown"

    android:paddingBottom="@dimen/activity_vertical_margin"

    android:paddingLeft="@dimen/activity_horizontal_margin"

    android:paddingRight="@dimen/activity_horizontal_margin"

    android:paddingTop="@dimen/activity_vertical_margin"

    tools:context=".MainActivity">

    <GridView

        android:id="@+id/apps_list"

        android:layout_width="match_parent"

        android:layout_height="wrap_content"

        android:layout_centerVertical="true"

        android:numColumns="4">

    </GridView>

</RelativeLayout>

然后单个item布局文件

application_layout.xml

<?xmlversion="1.0"encoding="utf-8"?>

<LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:orientation="vertical">

    <ImageView

        android:id="@+id/app_icon"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content" 

        android:layout_marginTop="15dp"/>

    <TextView

        android:id="@+id/app_title"

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:textSize="12sp"

        android:gravity="center"/>

</LinearLayout>

AndroidMainfest.xml 这里记得要添加两个设置

 <categoryandroid:name="android.intent.category.DEFAULT"/>

                <categoryandroid:name="android.intent.category.HOME"/>

源代码

package com.example.test;


import java.util.List;


import android.os.Bundle;
import android.app.Activity;
import android.content.ComponentName;
import android.content.Intent;
import android.content.pm.ResolveInfo;
import android.view.LayoutInflater;
import android.view.Menu;
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.widget.TextView;


public class MainActivity extends Activity {


private List<ResolveInfo>mApps;
GridView mGrid;
private OnItemClickListener listener=new OnItemClickListener(){


@Override
public void onItemClick(AdapterView<?> arg0, View view, int position,
long id) {
// TODO Auto-generated method stub
ResolveInfo info=mApps.get(position);
//该应用包名
String pkg=info.activityInfo.packageName;
//应用的主activity类
String cls=info.activityInfo.name;
ComponentName componet=new ComponentName(pkg,cls);
Intent i=new Intent();
i.setComponent(componet);
startActivity(i);
}

};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
loadApps();
setContentView(R.layout.activity_main);
mGrid=(GridView)findViewById(R.id.apps_list);

mGrid.setAdapter(new AppsAdapter());
mGrid.setOnItemClickListener(listener);
}


@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}


private void loadApps(){
Intent mainIntent=new Intent(Intent.ACTION_MAIN,null);
mainIntent.addCategory(Intent.CATEGORY_LAUNCHER);
mApps=getPackageManager().queryIntentActivities(mainIntent, 0);
}

public class AppsAdapter extends BaseAdapter{
public AppsAdapter(){

}
public View getView(int position,View convertView,ViewGroup parent){
ViewHolder holder=null;
if(convertView==null){
convertView=LayoutInflater.from(MainActivity.this).inflate(R.layout.application_layout,null);
holder=new ViewHolder();
holder.mAppIcon=(ImageView)convertView.findViewById(R.id.app_icon);
holder.mAppTitle=(TextView)convertView.findViewById(R.id.app_title);
convertView.setTag(holder);
}else{
holder=(ViewHolder)convertView.getTag();
}
ResolveInfo info=mApps.get(position);
holder.mAppIcon.setImageDrawable(info.loadIcon(getPackageManager()));
holder.mAppTitle.setText(info.loadLabel(getPackageManager()).toString());
return convertView;
}
private class ViewHolder{
ImageView mAppIcon;
TextView mAppTitle;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return mApps.size();
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return mApps.get(position);
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
}

}