Progress bar of the Android Control

The following describes ProgressBar in detail.

I. Description

The visual indicator in the progress of some operations shows the operation progress for the user, and it also has a secondary progress bar to display the intermediate progress, such as the progress in the buffer area of streaming media playback. A progress bar cannot be determined. In uncertain mode, the progress bar displays a circular animation. This mode is often used in applications. The length of a task is unknown.

Ii. Important XML attributes

Android: progressBarStyle: Default progress bar style

Android: progressBarStyleHorizontal: horizontal style

 

Iii. Important Methods

GetMax (): Maximum range of the returned progress bar

GetProgress (): returns the progress

GetSecondaryProgress (): returns the secondary progress

IncrementProgressBy (int diff): Specifies the increase progress.

IsIndeterminate (): indicates whether the progress bar is in uncertain mode.

SetIndeterminate (boolean indeterminate): sets the uncertain mode.

SetVisibility (int v): sets whether the progress bar is visible.

4. Important Events

OnSizeChanged (int w, int h, int oldw, int oldh): this event is triggered when the progress value changes.

V. Instances

1. layout File

[Html]
<? Xml version = "1.0" encoding = "UTF-8"?>
 
<LinearLayout xmlns: android = "http://schemas.android.com/apk/res/android"
Android: orientation = "vertical"
Android: layout_width = "match_parent"
Android: layout_height = "wrap_content">
 
<ProgressBar android: id = "@ + id/progress_horizontal"
Style = "? Android: attr/progressBarStyleHorizontal"
Android: layout_width = "200dip"
Android: layout_height = "wrap_content"
Android: max = "100"
Android: progress = "50"
Android: secondaryProgress = "75"/>
 
<TextView
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "Default progress bar"/>
 
<LinearLayout
Android: orientation = "horizontal"
Android: layout_width = "match_parent"
Android: layout_height = "wrap_content">
 
<Button android: id = "@ + id/decrease"
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "reduce"/>
 
<Button android: id = "@ + id/increase"
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "add"/>
 
</LinearLayout>
 
<TextView
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "Custom progress bar"/>
 
<LinearLayout
Android: orientation = "horizontal"
Android: layout_width = "match_parent"
Android: layout_height = "wrap_content">
 
<Button android: id = "@ + id/decrease_secondary"
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "second decrease"/>
 
<Button android: id = "@ + id/increase_secondary"
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "added second"/>
 
</LinearLayout>
 
</LinearLayout>

<? Xml version = "1.0" encoding = "UTF-8"?>

<LinearLayout xmlns: android = "http://schemas.android.com/apk/res/android"
Android: orientation = "vertical"
Android: layout_width = "match_parent"
Android: layout_height = "wrap_content">

<ProgressBar android: id = "@ + id/progress_horizontal"
Style = "? Android: attr/progressBarStyleHorizontal"
Android: layout_width = "200dip"
Android: layout_height = "wrap_content"
Android: max = "100"
Android: progress = "50"
Android: secondaryProgress = "75"/>

<TextView
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "Default progress bar"/>

<LinearLayout
Android: orientation = "horizontal"
Android: layout_width = "match_parent"
Android: layout_height = "wrap_content">

<Button android: id = "@ + id/decrease"
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "reduce"/>

<Button android: id = "@ + id/increase"
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "add"/>

</LinearLayout>

<TextView
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "Custom progress bar"/>

<LinearLayout
Android: orientation = "horizontal"
Android: layout_width = "match_parent"
Android: layout_height = "wrap_content">

<Button android: id = "@ + id/decrease_secondary"
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "second decrease"/>

<Button android: id = "@ + id/increase_secondary"
Android: layout_width = "wrap_content"
Android: layout_height = "wrap_content"
Android: text = "added second"/>

</LinearLayout>

</LinearLayout>

 

 

2. Java code

[Java]
Package wjq. WidgetDemo;
 
Import android. app. Activity;
Import android. OS. Bundle;
Import android. view. View;
Import android. view. Window;
Import android. widget. Button;
Import android. widget. ProgressBar;
 
Public class ProgressBarDemo extends Activity {
 
/* (Non-Javadoc)
* @ See android. app. Activity # onCreate (android. OS. Bundle)
*/
@ Override
Protected void onCreate (Bundle savedInstanceState ){
// TODO Auto-generated method stub
Super. onCreate (savedInstanceState );

RequestWindowFeature (Window. FEATURE_PROGRESS );
SetContentView (R. layout. probarpage );
SetProgressBarVisibility (true );

Final ProgressBar progressHorizontal = (ProgressBar) findViewById (R. id. progress_horizontal );
SetProgress (progressHorizontal. getProgress () * 100 );
SetSecondaryProgress (progressHorizontal. getSecondaryProgress () * 100 );

Button button = (Button) findViewById (R. id. increase );
Button. setOnClickListener (new Button. OnClickListener (){
Public void onClick (View v ){
ProgressHorizontal. incrementProgressBy (1 );
// Title progress is in range 0 .. 10000
SetProgress (100 * progressHorizontal. getProgress ());
}
});
 
Button = (Button) findViewById (R. id. decrease );
Button. setOnClickListener (new Button. OnClickListener (){
Public void onClick (View v ){
ProgressHorizontal. incrementProgressBy (-1 );
// Title progress is in range 0 .. 10000
SetProgress (100 * progressHorizontal. getProgress ());
}
});
 
Button = (Button) findViewById (R. id. increase_secondary );
Button. setOnClickListener (new Button. OnClickListener (){
Public void onClick (View v ){
ProgressHorizontal. incrementSecondaryProgressBy (1 );
// Title progress is in range 0 .. 10000
SetSecondaryProgress (100 * progressHorizontal. getSecondaryProgress ());
}
});
 
Button = (Button) findViewById (R. id. decrease_secondary );
Button. setOnClickListener (new Button. OnClickListener (){
Public void onClick (View v ){
ProgressHorizontal. incrementSecondaryProgressBy (-1 );
// Title progress is in range 0 .. 10000
SetSecondaryProgress (100 * progressHorizontal. getSecondaryProgress ());
}
});

}
 
}