How to Download an image in ANDROID programatically?
How to Download an pdf in ANDROID programatically?
Open new project and add these code.
This an simple example for downloading files from server in android programatically.
The java code to download the file.
package com.example.root.download;
import android.os.AsyncTask;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
public class MainActivity extends AppCompatActivity {
private static Button btnDownload;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnDownload = (Button) findViewById(R.id.btnDownload);
btnDownload.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//ok calll downloading
new Downloading().execute();
Toast.makeText(MainActivity.this,"Downloading completed",Toast.LENGTH_LONG).show();
}
});
}
//add downloading
private class Downloading extends AsyncTask<Void, Void, Void> {
@Override
protected Void doInBackground(Void... voids) {
try {
//This is the file we are going to download.
//Please add your server file location .
URL url = new URL("http://www.mission2win.in/pdf/pdf22.pdf");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
//Connect
urlConnection.connect();
//set path where to save the file
File SDCardRoot = Environment.getExternalStorageDirectory();
//create a new file to save
File file = new File(SDCardRoot,"pdf22.pdf");
FileOutputStream fileOutput = new FileOutputStream(file);
//stream used for reading the data from the internet
InputStream inputStream = urlConnection.getInputStream();
//create a buffer
byte[] buffer = new byte[124];
int bufferLength = 0;
while( (bufferLength = inputStream.read(buffer)) > 0){
fileOutput.write(buffer,0,bufferLength);
}
//close the output stream when complete
fileOutput.close();
}
catch (final MalformedURLException e){
showError("Error : MalformURLException " + e);
e.printStackTrace();
}
catch (final IOException e){
showError("Error : IOException " + e);
e.printStackTrace();
}
catch (final Exception e){
showError("Error : Please check your internet connection " + e);
}
return null;
}
void showError(final String err){
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(MainActivity.this,err,Toast.LENGTH_LONG).show();
}
});
}
}
}
This is the contents of xml file.
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.root.download.MainActivity">
<Button
android:id="@+id/btnDownload"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Download File"
/>
</RelativeLayout>
Add Internet and Write to External Directory permissions to AndroidManifest.xml
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.root.download">
<!-- Permission required for Downloading Files -->
<uses-permission android:name="android.permission.INTERNET" />
<!-- Permission required for Checking Internet Connection -->
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<!-- Permission required for Reading Writing SD Card/Memory -->
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
Now run the app on your Android device.
open failed: EACCES (Permission denied)
Verify permission and add this code to give a permission public static void verifyStoragePermissions(Activity activity) {
// Check if we have write permission
int permission = ActivityCompat.checkSelfPermission(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE);
if (permission != PackageManager.PERMISSION_GRANTED) {
// We don't have permission so prompt the user
ActivityCompat.requestPermissions(
activity,
PERMISSIONS_STORAGE,
REQUEST_EXTERNAL_STORAGE
);
}
}
Other wise add several permission to Manifest file.
<!-- Permission required for Downloading Files -->
<uses-permission android:name="android.permission.INTERNET" /> <!-- Permission required for Checking Internet Connection -->
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" /> <!-- Permission required for Reading Writing SD Card/Memory -->
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
Android download a file from remote server With progressbar
Create a new xml file inside res/layout folder and name it progressdialog.xml
<?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"
android:padding="10dp"
>
<TextView
android:id="@+id/heading"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#0F0"
android:text="Heading"
android:textStyle="bold|italic"
android:layout_marginTop="5dp"
/>
<ProgressBar
android:id="@+id/progressbar"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:progress="0"
android:layout_marginTop="5dp"
android:layout_marginBottom="10dp"
style="?android:attr/progressBarStyleHorizontal"
android:maxHeight="10dip"
android:minHeight="10dip"
/>
</LinearLayout>
Colored code add to Main_Activity.java
package com.example.root.download;
import android.app.Dialog;
import android.os.AsyncTask;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.Window;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
public class MainActivity extends AppCompatActivity {
private static Button btnDownload;
ProgressBar progressBar;
Dialog dialog;
int downloadedSize =0;
int totalSize=0;
TextView heading;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnDownload = (Button) findViewById(R.id.btnDownload);
btnDownload.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
showProgress();
//ok calll downloading
new Downloading().execute();
Toast.makeText(MainActivity.this,"Downloading completed",Toast.LENGTH_LONG).show();
}
});
}
//add downloading
private class Downloading extends AsyncTask<Void, Void, Void> {
@Override
protected Void doInBackground(Void... voids) {
try {
URL url = new URL("http://www.mission2win.in/pdf/pdf22.pdf");
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
//Connect
urlConnection.connect();
//set path where to save the file
File SDCardRoot = Environment.getExternalStorageDirectory();
//create a new file to save
File file = new File(SDCardRoot,"pdf22.pdf");
FileOutputStream fileOutput = new FileOutputStream(file);
//stream used for reading the data from the internet
InputStream inputStream = urlConnection.getInputStream();
//This is total size of the downloading file
totalSize = urlConnection.getContentLength();
runOnUiThread(new Runnable() {
@Override
public void run() {
progressBar.setMax(totalSize);
}
});
//create a buffer
byte[] buffer = new byte[124];
int bufferLength = 0;
while( (bufferLength = inputStream.read(buffer)) > 0){
fileOutput.write(buffer,0,bufferLength);
downloadedSize += bufferLength;
//Update progress bar
runOnUiThread(new Runnable() {
@Override
public void run() {
progressBar.setProgress(downloadedSize);
}
});
}
//close the output stream when complete
fileOutput.close();
//close dialog
dialog.dismiss();
}
catch (final MalformedURLException e){
showError("Error : MalformURLException " + e);
e.printStackTrace();
}
catch (final IOException e){
showError("Error : IOException " + e);
e.printStackTrace();
}
catch (final Exception e){
showError("Error : Please check your internet connection " + e);
}
return null;
}
void showError(final String err){
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(MainActivity.this,err,Toast.LENGTH_LONG).show();
}
});
}
}
void showProgress(){
dialog = new Dialog(MainActivity.this);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
dialog.setContentView(R.layout.progressdialog); //this is my created xml file
dialog.setTitle("Download Progress");
heading = (TextView) dialog.findViewById(R.id.heading);
heading.setText("Download starting ...");
dialog.show();
progressBar = (ProgressBar)dialog.findViewById(R.id.progressbar);
progressBar.setProgress(0);
}
}
