摘要:main.xml2.通过PackageManager的api查询已经安装的apkprivatevoidloadApps(){IntentmainIntent=newIntent;mainIntent.addCategory;mApps=getPackageManager().queryIntentActivities;}3.实现用于显示Gridview的Adapter,使其显示获得的应用程序列表ViewCode4.监听GridView的onItemClick事件设置一个监听器是为了当gridView的某项被点击时,会有一个回调函数通知我们。我们调用mGrid.setOnItemClickListener;设置一个监听器mGrid.setOnItemClickListener中的listener是一个接口,其类型为:android.widget.AdapterView.OnItemClickListenerprivateOnItemClickListenerlistener=newOnItemClickListener(){@OverridepublicvoidonItemClick(AdapterViewparent,Viewview,intposition,longid){//事件内容....}};5.启动被点击应用的activity一般来讲,我们根据position即可知道被点击的项目是哪一项了。现在我们根据被点击的项目,取出对应的应用程序数据,然后启动activity。用下面代码实现:publicvoidonItemClick(AdapterView˂?
第一步,把我们的应用程序作为home(即实现按下home键,启动自己的launcher.)
要把我们的应用程序作为home,只需要在AndroidManifest.xml中添加:
<category android:name="android.intent.category.HOME" />
<category android:name="android.intent.category.DEFAULT" />
AndroidManifest.xml 第二步,列出安装的应用程序
列出已经安装的应用程序是作为launcher比不可少的功能。下面我们就讲解怎样将应用程序列出来。程序运行后的样子如下:
1. 修改main.xml,在其中添加一个GridView用来显示应用程序列表。
main.xml 2 . 通过PackageManager的api 查询已经安装的apkprivatevoidloadApps() { Intent mainIntent =newIntent(Intent.ACTION_MAIN, null); mainIntent.addCategory(Intent.CATEGORY_LAUNCHER); mApps =getPackageManager().queryIntentActivities(mainIntent, 0); }
3. 实现用于显示Gridview的Adapter,使其显示获得的应用程序列表View Code 4.监听GridView的onItemClick事件
设置一个监听器是为了当gridView的某项被点击时,会有一个回调函数通知我们。
我们调用mGrid.setOnItemClickListener(listener); 设置一个监听器
mGrid.setOnItemClickListener(listener)中的listener是一个接口,其类型为:android.widget.AdapterView.OnItemClickListener
privateOnItemClickListener listener =newOnItemClickListener() { @Override publicvoidonItemClick(AdapterView<?>parent, View view, intposition,longid) { //事件内容....} };
5.启动被点击应用的activity
一般来讲,我们根据position即可知道被点击的项目是哪一项了。现在我们根据被点击的项目,取出对应的应用程序数据(主要是其中的主activity),然后启动activity。用下面代码实现:
publicvoidonItemClick(AdapterView<?>parent, View view, intposition,longid) { ResolveInfo info =mApps.get(position); //该应用的包名String pkg =info.activityInfo.packageName; //应用的主activity类String cls =info.activityInfo.name; ComponentName componet =newComponentName(pkg, cls); Intent i =newIntent(); i.setComponent(componet); startActivity(i); }
最后整个Activity的代码如下:
packageorg.bangchui.myhome; importjava.util.List; importandroid.app.Activity; importandroid.content.ComponentName; importandroid.content.Intent; importandroid.content.pm.ResolveInfo; importandroid.os.Bundle; importandroid.view.View; importandroid.view.ViewGroup; importandroid.widget.AdapterView; importandroid.widget.BaseAdapter; importandroid.widget.GridView; importandroid.widget.ImageView; importandroid.widget.AdapterView.OnItemClickListener; publicclassMyHome extendsActivity { privateList<ResolveInfo>mApps; GridView mGrid; privateOnItemClickListener listener =newOnItemClickListener() { @Override publicvoidonItemClick(AdapterView<?>parent, View view, intposition,longid) { ResolveInfo info=mApps.get(position); //该应用的包名String pkg =info.activityInfo.packageName; //应用的主activity类String cls =info.activityInfo.name; ComponentName componet =newComponentName(pkg, cls); Intent i =newIntent(); i.setComponent(componet); startActivity(i); } }; /**Called when the activity is first created. */@Override publicvoidonCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); loadApps(); setContentView(R.layout.main); mGrid =(GridView) findViewById(R.id.apps_list); mGrid.setAdapter(newAppsAdapter()); mGrid.setOnItemClickListener(listener); } privatevoidloadApps() { Intent mainIntent =newIntent(Intent.ACTION_MAIN, null); mainIntent.addCategory(Intent.CATEGORY_LAUNCHER); mApps =getPackageManager().queryIntentActivities(mainIntent, 0); } publicclassAppsAdapter extendsBaseAdapter { publicAppsAdapter() { } publicView getView(intposition, View convertView, ViewGroup parent) { ImageView i; if(convertView ==null) { i =newImageView(MyHome.this); i.setScaleType(ImageView.ScaleType.FIT_CENTER); i.setLayoutParams(newGridView.LayoutParams(50, 50)); } else{ i =(ImageView) convertView; } ResolveInfo info =mApps.get(position); i.setImageDrawable(info.activityInfo.loadIcon(getPackageManager())); returni; } publicfinalintgetCount() { returnmApps.size(); } publicfinalObject getItem(intposition) { returnmApps.get(position); } publicfinallonggetItemId(intposition) { returnposition; } } }