Android Application Development Cookbook: 93 Recipes for Building Winning Apps

 
Recipe 2.1 using Buttons
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43
public void onClick(View view)
{
Toast.makeText(getBaseContext(),
((Button) view).getText() + " was clicked!",
Toast.LENGTH_LONG).show();
}
};
You then set the two buttons’ click event handler to this class:
//---the two buttons are wired to the same event handler--- 
Button btn4 = (Button) findViewById(R.id.button4);
btn4.setOnClickListener(btnListener);
Button btn5 = (Button) findViewById(R.id.button5); 
btn5.setOnClickListener(btnListener);
The 
ToggleButton
behaves just like the 
Button
except that it displays a blue line indicating whether 
it is toggled: 
public void onToggle(View view) {
ToggleButton btn = (ToggleButton) view;
Toast.makeText(this, "Toggle mode: " + btn.isChecked(), 
Toast.LENGTH_SHORT).show();
}
You can check whether a 
ToggleButton
is toggled by checking its 
isChecked()
method. 
Figure 2-1 shows the buttons in action.
Figure 2-1
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44
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ChAPter 2
using Views to design the user interFAce
reCiPe 2.2 
using iMAge buttons
Android Versions
Level 1 and above
permissions
None
source code to download from Wrox.com
ImageButtons.zip
The previous recipe showed the 
Button
and 
ToggleButton
in action and the various ways to handle 
their events. This recipe describes how to display images on buttons. As the saying goes, a picture is 
worth a thousand words. Hence, sometimes it would be more intuitive and descriptive to display a 
picture on top of a button rather than words. 
solution
Consider the following code snippet in the 
activity_main.xml
file:
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
android:id="@+id/imageButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/ic_launcher"
android:onClick="onToggle" />
android:id="@+id/imageTextButton1" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content"
android:drawableTop="@drawable/ic_launcher"
android:text="Android"/>
android:id="@+id/imageTextButton2" 
android:layout_width="wrap_content" 
android:layout_height="wrap_content"
android:drawableLeft="@drawable/ic_launcher"
android:text="Android"/>
android:id="@+id/imageTextButton3" 
android:layout_width="wrap_content" 
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