android.content.pm包里的类都是管理应用程序的。
获取已安装应用程序信息
通过Activity的getPackageManager()方法可以得到PackageManager的对象
1.PackageManager 的getInstalledPackages(int flags)方法可以得到所有安装在机器上的程序的包信息类对象List<PackageInfo>,PackageInfo类中有一值applicationInfo可以得到Application的对象。
2.PackageManager的getInstalledApplications(int flags)方法可以得到所有安装在机器上的程序的application对象List<ApplicationInfo>;
Application类继承类PackageItemInfo,在PackageItemInfo类中有方法loadIcon(PackageManager pm)返回应用程序图标Drawable类型。有方法loadLabel(PackageManager pm)返回应用程序名称,CharSequence类型。
ApplicationInfo中无法获取版本号和版本名。PackageInfo类中有包名、版本名、版本号。
如果只需要安装程序的名字和图片而不需要版本号和版本名信息,用方法2获取ApplicationInfo。如果都需要,用方法1获取PackageInfo,再通过PackageInfo获取ApplicationInfo。
PackageItemInfo中有值
public int | icon | : A drawable resource identifier (in the package's resources) of this component's icon. |
public int | labelRes | : A string resource identifier (in the package's resources) of this component's label. |
是int型,基本用不上。
public String | packageName | : Name of the package that this item is in. |
这个是程序的包名,也就是说,可以在ApplicationInfo对象中得到安装程序的图片名字和包名。版本号和版本名只能在PackageInfo中获得。ApplicationInfo与PackageInfo中都能得到包名!
程序名和图片还可以通过PackageManager类获得,PackageManager有方法getApplicationIcon(String packageName)和getApplicationIcon(ApplicationInfo info)都可以获得应用程序的图片,getApplicationLabel(ApplicationInfo info)方法可以获得应用程序的名字。
下面这段代码可以得到所有已安装应用启动程序的Activity的信息,即Main Activity Info:
PackageManager pm = getPackageManager();
Intent filter = new Intent(Intent.ACTION_MAIN);
filter.addCategory(Intent.CATEGORY_LAUNCHER);
List<ResolveInfo>list = pm.queryIntentActivities(filter, PackageManager.GET_RESOLVED_FILTER);
启动手机里的第1个程序:
ComponentName cn =new ComponentName(list.get(0).activityInfo.packageName, list.get(0).activityInfo.name);
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK |
Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED);
intent.setComponent(cn);
startActivity(intent);
获取apk文件信息:
public static AppInfo getApkFileInfo(Context ctx, String apkPath) {
// System.out.println(apkPath);
long q=System.currentTimeMillis();
File apkFile = new File(apkPath);
if (!apkFile.exists() || !apkPath.toLowerCase().endsWith(".apk")) {
System.out.println("文件路径不正确");
return null;
}
AppInfo appInfoData;
String PATH_PackageParser = "android.content.pm.PackageParser";
String PATH_AssetManager = "android.content.res.AssetManager";
try {
//反射得到pkgParserCls对象并实例化,有参数
Class<?> pkgParserCls = Class.forName(PATH_PackageParser);
Class<?>[] typeArgs = {String.class};
Constructor<?> pkgParserCt = pkgParserCls.getConstructor(typeArgs);
Object[] valueArgs = {apkPath};
Object pkgParser = pkgParserCt.newInstance(valueArgs);
//从pkgParserCls类得到parsePackage方法
DisplayMetrics metrics = new DisplayMetrics();
metrics.setToDefaults();//这个是与显示有关的, 这边使用默认
typeArgs = new Class<?>[]{File.class,String.class,
DisplayMetrics.class,int.class};
Method pkgParser_parsePackageMtd = pkgParserCls.getDeclaredMethod(
"parsePackage", typeArgs);
valueArgs=new Object[]{new File(apkPath),apkPath,metrics,0};
//执行pkgParser_parsePackageMtd方法并返回
Object pkgParserPkg = pkgParser_parsePackageMtd.invoke(pkgParser,
valueArgs);
//从返回的对象得到名为"applicationInfo"的字段对象
if (pkgParserPkg==null) {
return null;
}
Field appInfoFld = pkgParserPkg.getClass().getDeclaredField(
"applicationInfo");
//从对象"pkgParserPkg"得到字段"appInfoFld"的值
if (appInfoFld.get(pkgParserPkg)==null) {
return null;
}
ApplicationInfo info = (ApplicationInfo) appInfoFld
.get(pkgParserPkg);
//反射得到assetMagCls对象并实例化,无参
Class<?> assetMagCls = Class.forName(PATH_AssetManager);
Object assetMag = assetMagCls.newInstance();
//从assetMagCls类得到addAssetPath方法
typeArgs = new Class[1];
typeArgs[0] = String.class;
Method assetMag_addAssetPathMtd = assetMagCls.getDeclaredMethod(
"addAssetPath", typeArgs);
valueArgs = new Object[1];
valueArgs[0] = apkPath;
//执行assetMag_addAssetPathMtd方法
assetMag_addAssetPathMtd.invoke(assetMag, valueArgs);
//得到Resources对象并实例化,有参数
Resources res = ctx.getResources();
typeArgs = new Class[3];
typeArgs[0] = assetMag.getClass();
typeArgs[1] = res.getDisplayMetrics().getClass();
typeArgs[2] = res.getConfiguration().getClass();
Constructor<Resources> resCt = Resources.class
.getConstructor(typeArgs);
valueArgs = new Object[3];
valueArgs[0] = assetMag;
valueArgs[1] = res.getDisplayMetrics();
valueArgs[2] = res.getConfiguration();
res = (Resources) resCt.newInstance(valueArgs);
// 读取apk文件的信息
appInfoData = new AppInfo();
if (info!=null) {
if (info.icon != 0) {// 图片存在,则读取相关信息
Drawable icon = res.getDrawable(info.icon);// 图标
appInfoData.setImage(icon);
}
else//若从apk文件里读取不出图片,则用默认图片填补image空白。
{
appInfoData.setImage(res.getDrawable(R.drawable.ic_launcher));
}
//若label标签没有,则名字为文件名
if (info.labelRes != 0) {
String neme = (String) res.getText(info.labelRes);// 名字
appInfoData.setName(neme);
}else {
String apkName=apkFile.getName();
appInfoData.setName(apkName.substring(0,apkName.lastIndexOf(".")));
}
String pkgName = info.packageName;// 包名
appInfoData.setPackagename(pkgName);
}else {
return null;//读不出info信息而返回空,影响待测。
}
PackageManager pm = ctx.getPackageManager();
PackageInfo packageInfo = pm.getPackageArchiveInfo(apkPath, PackageManager.GET_ACTIVITIES);
if (packageInfo != null) {
appInfoData.setVersion(packageInfo.versionName);//版本号
// appInfoData.setAppversionCode(packageInfo.versionCode+"");//版本码
}
//取得apk文件大小
File f=new File(apkPath);
if(f.length()/1024>1024)
{
appInfoData.setFilesize(f.length()/(1024*1024)+"M");
}
else
{
appInfoData.setFilesize(f.length()/1024+"kb");
}
appInfoData.setApkpath(apkPath);
System.out.println(System.currentTimeMillis()-q);
return appInfoData;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
上面的方法是以前百度搜的,的确有效,用的是java的反射实现的,当时没看懂,现在明白了是代码中很多没用的代码,不建议试用上面的代码,使用下面的代码:
public static Drawable getApkIcon(Context context, String apkPath) {
PackageManager pm = context.getPackageManager();
PackageInfo info = pm.getPackageArchiveInfo(apkPath,
PackageManager.GET_ACTIVITIES);
if (info != null) {
ApplicationInfo appInfo = info.applicationInfo;
appInfo.sourceDir = apkPath;
appInfo.publicSourceDir = apkPath;
try {
return appInfo.loadIcon(pm);
} catch (OutOfMemoryError e) {
Log.e("ApkIconLoader", e.toString());
}
}
return null;
}
--------------------------------------------------------------------获取拥有某权限的应用列表---------------------------------------------------------------------------
public List<PackageInfo> getAppListByPermission(String permissionName){
List<PackageInfo> appinfos = new ArrayList<PackageInfo>();
PackageManager mPackageManager = getPackageManager();
List<PackageInfo> mPackageInfo =
mPackageManager.getInstalledPackages(PackageManager.GET_PERMISSIONS);
// false framework switch
for(int i=0;i< mPackageInfo.size(); i++) {
String[] mPermissions;
// ignore local application ,keep third_party application stay
if((mPackageInfo.get(i).applicationInfo.flags & ApplicationInfo.FLAG_SYSTEM) != 0 )
{
Log.d("ss","OnePermissionTOApplicationList " + mPackageInfo.get(i).applicationInfo.flags + " " + ApplicationInfo.FLAG_SYSTEM);
continue;
}
// ignore local application ,keep third_party application stay
try {
mPermissions = mPackageManager.getPackageInfo(mPackageInfo.get(i).packageName, PackageManager.GET_PERMISSIONS).requestedPermissions;
if( mPermissions != null)
{
for(int j=0; j< mPermissions.length; j++)
{
if(permissionName.equals(mPermissions[j]))
{
appinfos.add(mPackageInfo.get(i));
}
}
}
}catch (Exception e) {
}
}
return appinfos;
}