Android手势操作(一)

mainActivity如下:

package cn.c;
import java.io.File;
import java.util.ArrayList;
import java.util.Set;
import android.app.Activity;
import android.gesture.Gesture;
import android.gesture.GestureLibraries;
import android.gesture.GestureLibrary;
import android.gesture.GestureOverlayView;
import android.gesture.GestureOverlayView.OnGestureListener;
import android.gesture.GestureOverlayView.OnGesturePerformedListener;
import android.gesture.Prediction;
import android.os.Bundle;
import android.os.Environment;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnKeyListener;
import android.widget.Button;
import android.widget.EditText;
/**
 * 需求描述:
 * 向手势库中保存一个手势
 * 错误总结:
 * 错误1:
 * 描述:在GestureOverlayView画一个手势后,该手势会
 * 里面消失,不会停留显示在GestureOverlayView控件上
 * 原因:
 * 没有在布局文件中为GestureOverlayView设置以下属性
 * android:gestureStrokeType="multiple"
 * 错误2:对于手势库文件gestureLibraryFile和手势库mGestureLibrary
 * 的理解有些偏差了.片面的理解为:这是两个独立的东西或者说
 * gestureLibraryFile中存放了一个mGestureLibrary
 * 应该这里理解:
 * mGestureLibrary就是一个文件!
 * 只是以前没有遇到这种文件,一时半会没有反应过来
 */
public class MainActivity extends Activity {
    private EditText mEditText;
    private GestureOverlayView mGestureOverlayView;
    private GestureLibrary mGestureLibrary;
    private Gesture mGesture;
    private Button mSaveButton;
    private Button mResetButton;
    private String mGestureLibraryPath;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        init();
    }

	private void init() {
		mEditText = (EditText) findViewById(R.id.editText);
		mEditText.setOnKeyListener(new OnKeyListener() {
			public boolean onKey(View v, int keyCode, KeyEvent event) {
				if (mGesture!=null&&mEditText.getText().toString().length()>0) {
					mSaveButton.setEnabled(true);
				} else {
					mSaveButton.setEnabled(false);
				}
				return false;
			}
		});
		mGestureOverlayView = 
		(GestureOverlayView) findViewById(R.id.gestureOverlayView);
		mSaveButton = (Button) findViewById(R.id.saveButton);
		mSaveButton.setOnClickListener(new ButtonOnClickListenerImpl());
		mSaveButton.setEnabled(false);
		mResetButton = (Button) findViewById(R.id.resetButton);
		mResetButton.setOnClickListener(new ButtonOnClickListenerImpl());
		//GestureLibrary文件的路径
		mGestureLibraryPath =
		Environment.getExternalStorageDirectory()+File.separator+"testgestures";
		//为GestureOverlayView添加监听事件
		mGestureOverlayView.addOnGestureListener(new GestureListenerImpl());
	}
	private class GestureListenerImpl implements OnGestureListener{
		//开始绘制手势
		public void onGestureStarted(GestureOverlayView overlay,MotionEvent event) {
			mSaveButton.setEnabled(false);
			mGesture=null;
		}
		public void onGesture(GestureOverlayView overlay, MotionEvent event) {
		}
        //手势绘制结束
		public void onGestureEnded(GestureOverlayView overlay, MotionEvent event) {
			mGesture=mGestureOverlayView.getGesture();
			if (mGesture!=null&&mEditText.getText().toString().length()>0) {
				mSaveButton.setEnabled(true);
			}
		}

		public void onGestureCancelled(GestureOverlayView overlay,MotionEvent event) {
		}
		
	}
	
	private class ButtonOnClickListenerImpl implements OnClickListener {
		public void onClick(View v) {
			switch (v.getId()) {
			case R.id.resetButton:
				mGestureOverlayView.clear(true);
				mSaveButton.setEnabled(false);
				mEditText.setText("");
				break;
			case R.id.saveButton:
				String gestureName = mEditText.getText().toString();
				try {
					File gestureLibraryFile = new File(mGestureLibraryPath);
					// 加载该路径下的手势库.
					// 若不存在,则会在路径下创建一个手势库
					mGestureLibrary = GestureLibraries.fromFile(mGestureLibraryPath);
					if (!gestureLibraryFile.exists()) {
						mGestureLibrary.addGesture(gestureName, mGesture);
						if (mGestureLibrary.save()) {
							//只有执行完mGestureLibrary.save()的时候
							//gestureLibraryFile文件才不为空
							//所以if只会执行一次,往后都执行else
							mSaveButton.setEnabled(false);
							mEditText.setText("");
							mGestureOverlayView.clear(true);
							System.out.println("xxxx0000 成功");
						} else {
							System.out.println("xxxx0000 失败");
						}
					} else {
						if (!mGestureLibrary.load()) {
							System.out.println("xxxx1111 加载手势库失败");
						} else {
							Set<String> gesturyies = mGestureLibrary.getGestureEntries();
							// 删除已经存在的同名的手势
							if (gesturyies.contains(gestureName)) {
								ArrayList<Gesture> list = mGestureLibrary.getGestures(gestureName);
								for (int i = 0; i < list.size(); i++) {
									mGestureLibrary.removeGesture(gestureName,list.get(i));
								}
							}
							// 添加手势
							mGestureLibrary.addGesture(gestureName, mGesture);
							// 判断手势是否保存成功
							if (mGestureLibrary.save()) {
								mGestureOverlayView.clear(true);
								mSaveButton.setEnabled(true);
								mEditText.setText("");
								System.out.println("xxxx1111 手势保存成功");
							} else {
								System.out.println("xxxx1111 手势保存失败");
							}

						}
					}
				} catch (Exception e) {
				}
				break;
			default:
				break;
			}
		}

	}
}

main.xml如下:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <LinearLayout
        android:id="@+id/linearLayout"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:orientation="horizontal" >

        <TextView
            android:id="@+id/textView"
            android:layout_width="100dip"
            android:layout_height="wrap_content"
            android:text="手势的名称:" />

        <EditText
            android:id="@+id/editText"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:hint="在此输入" />
    </LinearLayout>
 <android.gesture.GestureOverlayView
     android:id="@+id/gestureOverlayView"
     android:layout_width="fill_parent"
     android:layout_height="fill_parent"
     android:layout_below="@id/linearLayout"
     android:layout_marginBottom="50dip"
     android:gestureStrokeType="multiple"
  />
  <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="50dip"
        android:layout_alignParentBottom="true"
        android:orientation="horizontal" >
    <Button 
        android:id="@+id/saveButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="1" 
        android:text="保存"
        />
     <Button 
        android:id="@+id/resetButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="1" 
        android:text="重置"
        />
   </LinearLayout>
 
</RelativeLayout>