Question

即时通讯在我的应用程序中创建一个功能，从服务器上下载新版本的apk并安装但是即时面临问题经过这么多次切换我发现这个代码如下当我在这行c.connect();之后进行调试时，catch()并打印Toast消息有什么问题请帮我，我的网址正在工作你可以尝试在webbroser上有人给我这个在线apk网址

public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);



    Button  button = (Button) findViewById(R.id.button1);

    button.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {


   Update("https://dl.dropboxusercontent.com/u/245131571/SampleApp.apk");       



        }

    });



}





      public void Update(String apkurl){
          try {
                URL url = new URL(apkurl);
                HttpURLConnection c = (HttpURLConnection) url.openConnection();
                c.setRequestMethod("GET");

                c.connect();

 String PATH = Environment.getExternalStorageDirectory() + "/naz/";
                File file = new File(PATH);
                file.mkdirs();
                File outputFile = new File(file, "app.apk");
                FileOutputStream fos = new FileOutputStream(outputFile);

                InputStream is = c.getInputStream();

                byte[] buffer = new byte[1024];
                int len1 = 0;
                while ((len1 = is.read(buffer)) != -1) {
                    fos.write(buffer, 0, len1);
                }
                fos.close();
                is.close();//till here, it works fine - .apk is download to my sdcard in download file

                Intent promptInstall = new Intent(Intent.ACTION_VIEW)
                .setData(Uri.parse(PATH+"app.apk"))
                .setType("application/android.com.app");
                startActivity(promptInstall);//installation is not working

            } catch (IOException e) {
 Toast.makeText(getApplicationContext(), "Update error!", Toast.LENGTH_LONG).show();
            }
         }  



}

AndroidManifest

<uses-sdk
    android:minSdkVersion="8"
    android:targetSdkVersion="18" />
 <uses-permission android:name="android.permission.INTERNET"/>

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.WRITE_SYNC_SETTINGS"/>
<uses-permission android:name="android.permission.INSTALL_PACKAGES"/>
<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name="com.example.appinstall.MainActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

 </manifest>

Answer 1

Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(new File(Environment.getExternalStorageDirectory() + "/download/" + "app.apk")), "application/vnd.android.package-archive");
intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(intent);

Answer 2

请使用上述代码在下面找到完整的工作示例。这个答案只是为了使用上述权限（

）收集完整的工作示例

<uses-permission android:name="android.permission.INSTALL_PACKAGES"/>

在这里输入代码

活动如下：

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;

import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Environment;
import android.app.Activity;
import android.content.Intent;

import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button button = (Button) findViewById(R.id.button1);

        button.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {

                Update("https://dl.dropboxusercontent.com/u/245131571/SampleApp.apk");

            }

        });

    }

    public void Update(final String apkurl) {
        new AsyncTask<Void, String, String>() {
            String result="";
            @Override
            protected String doInBackground(Void... params) {
                try {
                    URL url = new URL(apkurl);
                    HttpURLConnection c = (HttpURLConnection) url
                            .openConnection();
                    c.setRequestMethod("GET");

                    c.connect();

                    String PATH = Environment.getExternalStorageDirectory()
                            + "/download/";
                    File file = new File(PATH);
                    file.mkdirs();
                    File outputFile = new File(file, "app.apk");
                    FileOutputStream fos = new FileOutputStream(outputFile);

                    InputStream is = c.getInputStream();

                    byte[] buffer = new byte[1024];
                    int len1 = 0;
                    while ((len1 = is.read(buffer)) != -1) {
                        fos.write(buffer, 0, len1);
                    }
                    fos.close();
                    is.close();
                    Intent intent = new Intent(Intent.ACTION_VIEW);
                    intent.setDataAndType(Uri.fromFile(new File(Environment.getExternalStorageDirectory() + "/download/" + "app.apk")), "application/vnd.android.package-archive");
                    intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                    startActivity(intent);

                } catch (IOException e) {
                    result="Update error! "+ e.getMessage();
                    e.printStackTrace();

                }
                return result;
            }

            protected void onPostExecute(String result) {

                Toast.makeText(getApplicationContext(), result,
                        Toast.LENGTH_LONG).show();
            };

        }.execute();

    }

}

如何从url安装apk并以编程方式安装

2 个答案: