ProgressBar
We can display the android progress bar dialog box to display the status of work being done e.g. downloading file, analyzing status of work etc.
In this example, we are displaying the progress dialog for dummy file download operation.
Here we are using android.app.ProgressDialog class to show the progress bar. Android ProgressDialog is the subclass of AlertDialog class.
The ProgressDialog class provides methods to work on progress bar like setProgress(), setMessage(), setProgressStyle(), setMax(), show() etc. The progress range of Progress Dialog is 0 to 10000.
Let's see a simple example to display progress bar in android.
progressBar.setCancelable(true);//you can cancel it by pressing back button
progressBar.setMessage("File downloading ...");
progressBar.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
progressBar.setProgress(0);//initially progress is 0
progressBar.setMax(100);//sets the maximum value 100
progressBar.show();//displays the progress bar
Android Progress Bar Example by ProgressDialog
Let's see a simple example to create progress bar using ProgressDialog class.
activity_main.xml
Drag one button from the pallete, now the activity_main.xml file will look like this:
File: activity_main.xml
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity" >
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="116dp"
android:text="download file" />
</RelativeLayout>
Activity class
Let's write the code to display the progress bar dialog box.
File: MainActivity.java
import android.app.ProgressDialog;
import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity {
Button btnStartProgress;
ProgressDialog progressBar;
private int progressBarStatus = 0;
private Handler progressBarHandler = new Handler();
private long fileSize = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
addListenerOnButtonClick();
}
public void addListenerOnButtonClick() {
btnStartProgress = findViewById(R.id.button);
btnStartProgress.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v) {
// creating progress bar dialog
progressBar = new ProgressDialog(v.getContext());
progressBar.setCancelable(true);
progressBar.setMessage("File downloading ...");
progressBar.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
progressBar.setProgress(0);
progressBar.setMax(100);
progressBar.show();
//reset progress bar and filesize status
progressBarStatus = 0;
fileSize = 0;
new Thread(new Runnable() {
public void run() {
while (progressBarStatus < 100) {
// performing operation
progressBarStatus = doOperation();
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
// Updating the progress bar
progressBarHandler.post(new Runnable() {
public void run() {
progressBar.setProgress(progressBarStatus);
}
});
}
// performing operation if file is downloaded,
if (progressBarStatus >= 100) {
// sleeping for 1 second after operation completed
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}
// close the progress bar dialog
progressBar.dismiss();
}
}
}).start();
}//end of onClick method
});
}
// checking how much file is downloaded and updating the filesize
public int doOperation() {
//The range of ProgressDialog starts from 0 to 10000
while (fileSize <= 10000) {
fileSize++;
if (fileSize == 1000) {
return 10;
} else if (fileSize == 2000) {
return 20;
} else if (fileSize == 3000) {
return 30;
} else if (fileSize == 4000) {
return 40; // you can add more else if
}
/* else {
return 100;
}*/
}//end of while
return 100;
}//end of doOperation
}
Output:
