Android：手势识别
实现手势识别，首先必须有手势库，由一个应用GestureBuilder生成，生成的库放入res/raw文件夹下。
第一步：建立手势库
使用SDK自带例子GestureBuilder建立手势库（位置：android-sdk-windows\samples\android-8\GestureBuilder）。使用GestureBuilder之前，你需要恢复其到开发环境【拷贝一般工程的三个文件：default.properties、.class、.project】，然后进行编绎并部署到手机上。此时，就可以使用GestureBuilder建立手势库，生成的手势库文件在SCDard上，默认文件名称为：gestures
第二步：在应用中加载手势库文件，然后开发手势识别代码。
把手势库文件gestures文件拷贝到项目的res/raw目录下。然后在布局文件中添加用于手势绘制的View：
<android.gesture.GestureOverlayView
android:id="@+id/gestures"
android:layout_width="fill_parent“ android:layout_height="0dip"
android:layout_weight="1.0"
/>
大多数情况下，手势都是通过一笔完成。然而有一些特别的需求就需要通过多个笔画来实现，这时可以使用 gestureStrokeType 属性进行设置： Multiple:1<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<android.gesture.GestureOverlayView
android:id="@+id/gestures"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:gestureStrokeType="multiple"
/>
<Button
android:layout_weight="0"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/recognize"
android:onClick="find"
/>
</LinearLayout>
public class MainActivity extends Activity {
private static final String TAG = "MainActivity";
private GestureLibrary library;
private Gesture mgesture;
private GestureOverlayView overlayView;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
library = GestureLibraries.fromRawResource(this, R.raw.gestures);//从res/raw中的gestures库
library.load();
overlayView = (GestureOverlayView) this.findViewById(R.id.gestures);
//只针对单笔手势：overlayView.addOnGesturePerformedListener(new GesturePerformedListener());
overlayView.addOnGestureListener(new GestureListener());
}
public void find(View v){
recognize(mgesture);
overlayView.clear(true);
}
private final class GestureListener implements OnGestureListener{
public void onGestureStarted(GestureOverlayView overlay, MotionEvent event) {
Log.i(TAG, "onGestureStarted()");
}
public void onGesture(GestureOverlayView overlay, MotionEvent event) {
Log.i(TAG, "onGesture()");
}
public void onGestureEnded(GestureOverlayView overlay, MotionEvent event) {
Log.i(TAG, "onGestureEnded()");
mgesture = overlay.getGesture();
}
public void onGestureCancelled(GestureOverlayView overlay, MotionEvent event) {
Log.i(TAG, "onGestureCancelled()");
}
}
private final class GesturePerformedListener implements OnGesturePerformedListener{
public void onGesturePerformed(GestureOverlayView overlay, Gesture gesture) {
recognize(gesture);
}
}
private void recognize(Gesture gesture) {
ArrayList<Prediction> predictions = library.recognize(gesture);
if(!predictions.isEmpty()){
Prediction prediction = predictions.get(0);
if(prediction.score >= 6){
if("zhangxx".equals(prediction.name)){
Intent intent = new Intent(Intent.ACTION_CALL, Uri.parse("tel:1350505050"));
startActivity(intent);
}else if("close".equals(prediction.name)){
finish();//关闭Activity
}
}else{
Toast.makeText(getApplicationContext(), R.string.low, 1).show();
}
}else{
Toast.makeText(getApplicationContext(), R.string.notfind, 1).show();
}
}
@Override
protected void onDestroy() {
super.onDestroy();
android.os.Process.killProcess(android.os.Process.myPid());//关闭应用
}
}