android动态加载已安装apk中的方法
16lz
2022-04-27
在android开发中,有很多时候是需要用到动态加载的,今天学习在android中动态加载已安装的apk中的方法。
首先,我们需要新建一个用来被加载的android工程,暂且给他取名叫做:plugproj
在plugproj中新建一个类Dynamic,在这个类中,我们新建一些方法,等会我们会分别在该工程安装和没有安装的情况下加载这些方法,Dynamic.java如下:
package com.example.plugproj;import android.app.Activity;import android.widget.Toast;public class Dynamic {Activity mActivity = null;public void init(Activity activity) {// TODO Auto-generated method stubmActivity = activity;}public void showDialog() {// TODO Auto-generated method stubToast.makeText(mActivity, "show dialog test gaga",Toast.LENGTH_LONG).show();}public void showWindow() {// TODO Auto-generated method stubToast.makeText(mActivity, "show window test gaga",Toast.LENGTH_LONG).show();}public int addMethod(int a, int b) {// TODO Auto-generated method stubreturn a + b;}}可以看到init方法中,我们为其mActivity赋值,这是为了得到context对象,好让toast可以执行。
这里还需要注意,我们需要为plugproj工程的启动的activity中配置一个action,好让我们可以通过这个action来加载对应的包,如下:
<activity android:name="com.example.plugproj.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> <intent-filter> <action android:name="com.haha.android.plugin"/> </intent-filter> </activity>
安装plugproj工程。
接下来看看另一个主工程,即加载plugproj的工程,主要代码如下:
//创建一个意图,用来找到指定的apk Intent intent = new Intent("com.haha.android.plugin", null); //获得包管理器 PackageManager pm = getPackageManager(); List<ResolveInfo> resolveinfoes = pm.queryIntentActivities(intent, 0); //获得指定的activity的信息 ActivityInfo actInfo = resolveinfoes.get(0).activityInfo; //获得包名 String pacageName = actInfo.packageName; //获得apk的目录或者jar的目录 String apkPath = actInfo.applicationInfo.sourceDir; //dex解压后的目录,注意,这个用宿主程序的目录,android中只允许程序读取写自己 //目录下的文件 String dexOutputDir = getApplicationInfo().dataDir; //native代码的目录 String libPath = actInfo.applicationInfo.nativeLibraryDir; //创建类加载器,把dex加载到虚拟机中 DexClassLoader calssLoader = new DexClassLoader(apkPath, dexOutputDir, libPath, this.getClass().getClassLoader()); try {clazz = calssLoader.loadClass(pacageName+".Dynamic"); obj = clazz.newInstance();Method initMethod = clazz.getDeclaredMethod("init",Activity.class);initMethod.invoke(obj,MainActivity.this);} catch (ClassNotFoundException e) {e.printStackTrace();} catch (InstantiationException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IllegalArgumentException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (NoSuchMethodException e) {// TODO Auto-generated catch blocke.printStackTrace();}接下来是执行上面三个方法的onclick事件:
@Overridepublic void onClick(View arg0) {// TODO Auto-generated method stubtry {switch (arg0.getId()) {case R.id.id_dialog:Method dialogMethod = clazz.getDeclaredMethod("showDialog",null);dialogMethod.invoke(obj, null);Log.d("Tag","show dialog runs ...");break;case R.id.id_window:Method windowMethod = clazz.getDeclaredMethod("showWindow",null);windowMethod.invoke(obj,null);Log.d("Tag","show window runs ...");break;case R.id.id_plus:Class[] param = new Class[2]; param[0] = Integer.TYPE; param[1] = Integer.TYPE; Method method = clazz.getDeclaredMethod("addMethod",param); int result = (Integer) method.invoke(obj, 22,33);Toast.makeText(MainActivity.this,"result is :"+result,Toast.LENGTH_SHORT).show();Log.d("Tag","add runs ...");break;default:Toast.makeText(MainActivity.this,"no property id",Toast.LENGTH_LONG).show();}} catch (NoSuchMethodException e) {e.printStackTrace();} catch (IllegalAccessException e) {e.printStackTrace();} catch (IllegalArgumentException e) {e.printStackTrace();} catch (InvocationTargetException e) {e.printStackTrace();}}
这样就实现了加载已经安装的apk中的方法。
接下来看看加载已经打包成为jar文件的方式:
首先需要将plugproj导出为jar文件,我们这里导出为plugproj.jar,注意这时候的jar文件在android手机上是不能直接加载的,我们需要将他转换成dex文件,怎么转换呢,在sdk下有一个dx工具,可以用它来实现,将plugproj.jar拷贝到拥有dx文件的目录下,一般是在platform_tool有时在build_tools文件夹下,然后用命令进入该文件下:
执行如下命令:
dx --dex --output 优化过的jar 没有优化过的jar
此时就会生成一个优化过的jar文件,这个jar文件就是我们的android手机可以直接加载的。将该jar文件拷贝到手机指定的目录下:
以下是关键代码:
String path = "/storage/sdcard0/183/mydynamic_help.jar";dexPath = getDir("dex", Context.MODE_PRIVATE).getAbsolutePath();dexClassLoader = new DexClassLoader(path, dexPath, null, getClassLoader());try {clazz = dexClassLoader.loadClass("com.example.plugproj.Dynamic");try {obj = clazz.newInstance();Method method = clazz.getDeclaredMethod("init",Activity.class);method.invoke(obj, MainActivity.this);Log.d("Tag","dynamic init runs ...");} catch (InstantiationException e1) {e1.printStackTrace();} catch (IllegalAccessException e1) {e1.printStackTrace();} catch (NoSuchMethodException e) {e.printStackTrace();} catch (IllegalArgumentException e) {e.printStackTrace();} catch (InvocationTargetException e) {e.printStackTrace();}} catch (ClassNotFoundException e) {e.printStackTrace();}为按钮绑定onclick事件:
public void onClick(View arg0) {// TODO Auto-generated method stubtry {switch (arg0.getId()) {case R.id.id_dialog:Method method = clazz.getDeclaredMethod("showDialog",null);method.invoke(obj, null);Log.d("Tag","show dialog runs ...");break;case R.id.id_window:method = clazz.getDeclaredMethod("showWindow",null);method.invoke(obj, null);Log.d("Tag","show window runs ...");break;case R.id.id_plus:<span style="white-space:pre"></span>Class[]param = new Class[2];param[0] = Integer.TYPE;param[1] = Integer.TYPE; method = clazz.getDeclaredMethod("addMethod",param);int result = (Integer) method.invoke(obj,23,25);<span style="white-space:pre"></span>Toast.makeText(MainActivity.this,"result is :"+result,Toast.LENGTH_SHORT).show();Log.d("Tag","add runs ...");break;<span style="white-space:pre"></span>default:Toast.makeText(MainActivity.this,"no property id",Toast.LENGTH_LONG).show();}} catch (NoSuchMethodException e) {e.printStackTrace();} catch (IllegalAccessException e) {e.printStackTrace();} catch (IllegalArgumentException e) {e.printStackTrace();} catch (InvocationTargetException e) {e.printStackTrace();}}最后千万要记住,添加读写sd卡的权限。
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
源码下载
动态加载jar
更多相关文章
- android启动过程及各个镜像间的关系
- Android自适应不同屏幕几种方法
- Android:异步调用详解
- Android与H5交互,以及WebView加载进度条
- Android(安卓)应用没有桌面图标
- 浅谈Java中Collections.sort对List排序的两种方法
- NPM 和webpack 的基础使用
- Python list sort方法的具体使用
- 【阿里云镜像】使用阿里巴巴DNS镜像源——DNS配置教程