从LINUX 驱动 到APK （4）

实现简单的apk，实现对对应节点的访问

　　此次使用apk实现对相应节点的访问。

　　实现apk，主要分为两个部分：实现相应的apk主体部分，编译生成apk

　　一、实现相应的apk主体部分

　　由于本人对Java不是很熟悉，过借鉴了老罗的代码，不同之处此次使用的Android studio来新建一个apk工程取名为welcome，选择Android6.0的sdk。

　　1、主程序 welcome.java

　　　　生成的代码需要修改相应的import 模块跟代码，以便使用mtk代码，同时由于引用了自己的代码故在Android studio 中编译会报错

package com.example.atlas.welcome;

//import com.example.atlas.welcome.R;
//import android.support.v7.app.AppCompatActivity;
import android.app.Activity;
import android.os.Bundle;
import android.os.ServiceManager;
import android.os.IWelcomeService;
import android.os.RemoteException;
import android.util.Log;
import android.util.EventLog;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.textservice.TextServicesManager;
import android.widget.Button;
import android.widget.EditText;
import java.io.IOException;
import java.util.ArrayList;

import android.app.ListActivity;
import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.graphics.drawable.Drawable;

public class welcome extends Activity implements  OnClickListener {
    private final static String LOG_TAG = "atlas.welcome";
    private IWelcomeService welcomeService = null;
    private EditText valueText = null;
    private Button readButton = null;
    private Button writeButton = null;
    private Button clearButton = null;

    // called when the activity is first created.
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_welcome);
        welcomeService = IWelcomeService.Stub.asInterface(ServiceManager.getService("welcome"));
        valueText = (EditText)findViewById(R.id.edit_value);
        readButton = (Button)findViewById(R.id.button_read);
        writeButton = (Button)findViewById(R.id.button_write);
        clearButton = (Button)findViewById(R.id.button_clear);

        readButton.setOnClickListener(this);
        writeButton.setOnClickListener(this);
        clearButton.setOnClickListener(this);

        Log.i(LOG_TAG,"Welcome Activity Created");
    }
    @Override
    public void onClick(View v){
        if(v.equals(readButton)){
            try{
                int val = welcomeService.getVal();
                String text = String.valueOf(val);
                valueText.setText(text);
            }catch (RemoteException e){
                Log.e(LOG_TAG,"Remote Exception while reading value from device.");
            }
        }else if(v.equals(writeButton)){
            try{
                String text = valueText.getText().toString();
                int val = Integer.parseInt(text);
                welcomeService.setVal(val);
            }catch (RemoteException e){
                Log.e(LOG_TAG,"Remote Exception while writing value to device.");
            }
        }else if(v.equals(clearButton)){
            String text = "";
            valueText.setText(text);
        }
    }
}

　　1.2 修改layout 目录下的activity_welcome.xml 文件

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  
   android:orientation="vertical"  
   android:layout_width="fill_parent"  
   android:layout_height="fill_parent">  
   <LinearLayout  
      android:layout_width="fill_parent"  
      android:layout_height="wrap_content"  
      android:orientation="vertical"   
      android:gravity="center">  
      <TextView   
         android:layout_width="wrap_content"  
         android:layout_height="wrap_content"   
         android:text="@string/value">  
      </TextView>  
      <EditText   
         android:layout_width="fill_parent"  
         android:layout_height="wrap_content"   
         android:id="@+id/edit_value"  
         android:hint="@string/hint">  
      </EditText>  
   </LinearLayout>  
   <LinearLayout  
      android:layout_width="fill_parent"  
      android:layout_height="wrap_content"  
      android:orientation="horizontal"   
      android:gravity="center">  
      <Button   
         android:id="@+id/button_read"  
         android:layout_width="wrap_content"  
         android:layout_height="wrap_content"  
         android:text="@string/read">  
      </Button>  
      <Button   
         android:id="@+id/button_write"  
         android:layout_width="wrap_content"  
         android:layout_height="wrap_content"  
         android:text="@string/write">  
      </Button>  
      <Button   
         android:id="@+id/button_clear"  
         android:layout_width="wrap_content"  
         android:layout_height="wrap_content"  
         android:text="@string/clear">  
      </Button>  
   </LinearLayout>  
</LinearLayout>  

　　1.3、 字符串文件res/values/strings.xml

<resources>
    <string name="app_name">welcome</string>
   <string name="value">Value</string>
   <string name="hint">Please input a value...</string>
   <string name="read">Read</string>
   <string name="write">Write</string>
   <string name="clear">Clear</string>
</resources>

　　1.4 修改styles.xml

<?xml version="1.0" encoding="utf-8"?>
<!--
/*
 * Copyright (C) 2010, The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); 
 * you may not use this file except in compliance with the License. 
 * You may obtain a copy of the License at 
 *
 *     http://www.apache.org/licenses/LICENSE-2.0 
 *
 * Unless required by applicable law or agreed to in writing, software 
 * distributed under the License is distributed on an "AS IS" BASIS, 
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 
 * See the License for the specific language governing permissions and 
 * limitations under the License.
 */
-->

<resources>
    <style name="TallTitleBarTheme" parent="android:Theme.NoTitleBar">
        <item name="android:windowContentOverlay">@null</item>
    </style>
</resources>

　　1.5 程序描述文件AndroidManifest.xml：

<?xml version="1.0" encoding="utf-8"?>  
<manifest xmlns:android="http://schemas.android.com/apk/res/android"  
    package="com.example.atlas.welcome"  
    android:sharedUserId="android.uid.log"
    >
    <application
        android:label="welcome" >
        <activity
            android:name=".welcome"
            android:label="welcome" >
        <intent-filter>  
            <action android:name="android.intent.action.MAIN" />  
            <category android:name="android.intent.category.LAUNCHER" />  
        </intent-filter>  
    </activity>  
</application>  
</manifest>   

　　二、编译生成apk

　　2.1、在适当的位置建立app目录，此次选择packagesapps建立welcome目录。

　　　　将Android studio 建立的源文件目录 welcomeappsrcmain 下的的文件copy到welcome目录下。

　　2.2、添加Android.mk 文件，添加编译规则

LOCAL_PATH:= $(call my-dir)

include $(CLEAR_VARS)
LOCAL_MODULE_TAGS:=optional

LOCAL_SRC_FILES := $(call all-java-files-under, java)

LOCAL_PACKAGE_NAME:=welcome
LOCAL_CERTIFICATE := platform
include $(BUILD_PACKAGE)
#include $(call all-makefiles-under,$(LOCAL_PATH))

　　　至此apk代码部分完成。

　　三、编译，下载，验证

　　　　使用mmm package/apps/welcome 编译即可，打包下载或者直接安装。

　　 如有相关权限问题，添加对应的权限即可。至此，从kernel 到apk部分代码完成。