Android recognizing gestures
I imported the gesture example and created my own app. There is a button and the gestureoverlayview in the layout. The button starts the GestureBuilderActivity.class, where I can add or remove gestures (this is the example). Under the button, in the GestureOverlayView I can draw gestures. Layout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<Button
android:layout_width=开发者_如何学JAVA"fill_parent"
android:layout_height="wrap_content"
android:text="Click to see gestures"
android:id="@+id/Button01"
/>
<android.gesture.GestureOverlayView
android:id="@+id/gestures"
android:layout_width="fill_parent"
android:layout_height="0dip"
android:layout_weight="1.0" />
</LinearLayout>
From the example I know that this is where I find the gestures:
final String path = new File(Environment.getExternalStorageDirectory(),
"gestures").getAbsolutePath();
and the toast msg shows (still in the example) that the gesture is saved in /mnt/sdcard/gestures:
Toast.makeText(this, getString(R.string.save_success, path), Toast.LENGTH_LONG).show();
How can I make the app recognize the gesture I draw and show me its name in a toast msg?
First, I would read this short article that explains how to use gestures.
To recognize a gesture you need to provide an OnGesturePerformedListener to GestureOverlayView. In this example, I just had the Activity implement the OnGesturePerformedListener.
public class MyActivity extends Activity implements OnGesturePerformedListener {
private GestureLibrary mGestures;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// I use resources but you may want to use GestureLibraries.fromFile(path)
mGestures = GestureLibraries.fromRawResource(this, R.raw.gestures);
if (!mGestures.load()) {
showDialog(DIALOG_LOAD_FAIL);
finish();
}
// register the OnGesturePerformedListener (i.e. this activity)
GestureOverlayView gesturesView = (GestureOverlayView) findViewById(R.id.gestures);
gesturesView.addOnGesturePerformedListener(this);
}
public void onGesturePerformed(GestureOverlayView overlay, Gesture gesture) {
ArrayList<Prediction> predictions = mGestures.recognize(gesture);
// Determine if a gesture was performed.
// This can be tricky, here is a simple approach.
Prediction prediction = (predictions.size() != 0) ? predictions.get(0) : null;
prediction = (prediction.score >= 1.0) ? prediction: null;
if (prediction != null) {
// do something with the prediction
Toast.makeText(this, prediction.name + "(" + prediction.score + ")", Toast.LENGTH_LONG).show();
}
}
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