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revise code sample for callback interface

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Change-Id: I8e27e2579dcc5cb84a71c74769fb89bb639e16ba
This commit is contained in:
Scott Main
2012-10-17 10:42:54 -07:00
parent e249763db1
commit 07322102e5
1 changed files with 28 additions and 33 deletions
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61
docs/html/guide/topics/ui/dialogs.jd
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@ -119,7 +119,7 @@ onCreateDialog()} callback method.</p>
a {@link android.support.v4.app.DialogFragment}:</p>
<pre>
public class FireMissilesDialog extends DialogFragment {
public class FireMissilesDialogFragment extends DialogFragment {
&#64;Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
// Use the Builder class for convenient dialog construction
@ -469,7 +469,7 @@ public Dialog onCreateDialog(Bundle savedInstanceState) {
})
.setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
NoticeDialog.this.getDialog().cancel();
LoginDialogFragment.this.getDialog().cancel();
}
});
return builder.create();
@ -497,15 +497,15 @@ in the <a href="{@docRoot}guide/topics/manifest/activity-element.html">{@code
<p>When the user touches one of the dialog's action buttons or selects an item from its list,
your {@link android.support.v4.app.DialogFragment} might perform the necessary
action itself, but often you'll want to deliver the event to the activity or fragment that
opened the dialog. To do this, define an interface with a method for each type of click event,
then implement that interface in the host component that will
opened the dialog. To do this, define an interface with a method for each type of click event.
Then implement that interface in the host component that will
receive the action events from the dialog.</p>
<p>For example, here's a {@link android.support.v4.app.DialogFragment} that defines an
interface through which it delivers the events back to the host activity:</p>
<pre>
public class NoticeDialog extends DialogFragment {
public class NoticeDialogFragment extends DialogFragment {
/* The activity that creates an instance of this dialog fragment must
* implement this interface in order to receive event callbacks.
@ -516,48 +516,44 @@ public class NoticeDialog extends DialogFragment {
}
// Use this instance of the interface to deliver action events
static NoticeDialogListener mListener;
/* Call this to instantiate a new NoticeDialog.
* @param activity The activity hosting the dialog, which must implement the
* NoticeDialogListener to receive event callbacks.
* @returns A new instance of NoticeDialog.
* @throws ClassCastException if the host activity does not
* implement NoticeDialogListener
*/
public static NoticeDialog newInstance(Activity activity) {
NoticeDialogListener mListener;
// Override the Fragment.onAttach() method to instantiate the NoticeDialogListener
&#64;Override
public void onAttach(Activity activity) {
super.onAttach(activity);
// Verify that the host activity implements the callback interface
try {
// Instantiate the NoticeDialogListener so we can send events with it
// Instantiate the NoticeDialogListener so we can send events to the host
mListener = (NoticeDialogListener) activity;
} catch (ClassCastException e) {
// The activity doesn't implement the interface, throw exception
throw new ClassCastException(activity.toString()
+ " must implement NoticeDialogListener");
}
NoticeDialog frag = new NoticeDialog();
return frag;
}
...
}
</pre>
<p>The activity hosting the dialog creates and shows an instance of the dialog
by calling {@code NoticeDialog.newInstance()} and receives the dialog's
<p>The activity hosting the dialog creates an instance of the dialog
with the dialog fragment's constructor and receives the dialog's
events through an implementation of the {@code NoticeDialogListener} interface:</p>
<pre>
public class MainActivity extends FragmentActivity
implements NoticeDialog.NoticeDialogListener{
implements NoticeDialogFragment.NoticeDialogListener{
...
public void showNoticeDialog() {
// Create an instance of the dialog fragment and show it
DialogFragment dialog = NoticeDialog.newInstance(this);
dialog.show(getSupportFragmentManager(), "NoticeDialog");
DialogFragment dialog = new NoticeDialogFragment();
dialog.show(getSupportFragmentManager(), "NoticeDialogFragment");
}
// The dialog fragment receives a reference to this Activity through the
// Fragment.onAttach() callback, which it uses to call the following methods
// defined by the NoticeDialogFragment.NoticeDialogListener interface
&#64;Override
public void onDialogPositiveClick(DialogFragment dialog) {
// User touched the dialog's positive button
@ -573,11 +569,12 @@ public class MainActivity extends FragmentActivity
</pre>
<p>Because the host activity implements the {@code NoticeDialogListener}&mdash;which is
enforced by the {@code newInstance()} method shown above&mdash;the dialog fragment can use the
enforced by the {@link android.support.v4.app.Fragment#onAttach onAttach()}
callback method shown above&mdash;the dialog fragment can use the
interface callback methods to deliver click events to the activity:</p>
<pre>
public class NoticeDialog extends DialogFragment {
public class NoticeDialogFragment extends DialogFragment {
...
&#64;Override
@ -588,13 +585,13 @@ public class NoticeDialog extends DialogFragment {
.setPositiveButton(R.string.fire, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
// Send the positive button event back to the host activity
mListener.onDialogPositiveClick(NoticeDialog.this);
mListener.onDialogPositiveClick(NoticeDialogFragment.this);
}
})
.setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
// Send the negative button event back to the host activity
mListener.onDialogPositiveClick(NoticeDialog.this);
mListener.onDialogPositiveClick(NoticeDialogFragment.this);
}
});
return builder.create();
@ -604,8 +601,6 @@ public class NoticeDialog extends DialogFragment {
<h2 id="ShowingADialog">Showing a Dialog</h2>
<p>When you want to show your dialog, create an instance of your {@link
@ -621,7 +616,7 @@ android.support.v4.app.Fragment}. For example:</p>
<pre>
public void confirmFireMissiles() {
DialogFragment newFragment = FireMissilesDialog.newInstance(this);
DialogFragment newFragment = new FireMissilesDialogFragment();
newFragment.show(getSupportFragmentManager(), "missiles");
}
</pre>
@ -653,7 +648,7 @@ onCreateView()} callback.</p>
dialog or an embeddable fragment (using a layout named <code>purchase_items.xml</code>):</p>
<pre>
public class CustomLayoutDialog extends DialogFragment {
public class CustomDialogFragment extends DialogFragment {
/** The system calls this to get the DialogFragment's layout, regardless
of whether it's being displayed as a dialog or an embedded fragment. */
&#64;Override
@ -683,7 +678,7 @@ or a fullscreen UI, based on the screen size:</p>
<pre>
public void showDialog() {
FragmentManager fragmentManager = getSupportFragmentManager();
CustomLayoutDialog newFragment = new CustomLayoutDialog();
CustomDialogFragment newFragment = new CustomDialogFragment();
if (mIsLargeLayout) {
// The device is using a large layout, so show the fragment as a dialog