增加手势和识别手势

最新推荐文章于 2025-05-07 18:09:25 发布

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本文介绍如何使用Android的GestureOverlayView组件实现手势绘制与识别。详细展示了如何创建手势库、保存手势到文件及从文件加载手势进行比对识别的过程。

gestureoverlayview组件是Android提供给开发者所使用绘制手势的控件，但是这个控件不是标准的控件需要使用全名，android.gesture.GestureOverlayView。

下方代码是增加手势和识别手势的实例代码：

一、增加手势

1，xml界面文件

<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"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:id="@+id/textview"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="请在下方绘制手势" />

    <!-- 非绘图组件，而是绘制手势的一个组件。他不是标准的绘图组件,使用全名 -->
    <android.gesture.GestureOverlayView
        android:id="@+id/gesture"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gestureStrokeType="single" ><!-- 是否需要一笔完成，multiple（多笔） -->
    </android.gesture.GestureOverlayView>

</RelativeLayout>
--save.xml--
<pre name="code" class="java">  <LinearLayout android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <TextView android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="8dip"
            android:text="MyGesture"/>
        <EditText android:id="@+id/gesture_name"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>
    </LinearLayout>
    	<ImageView android:id="@+id/show"
    	    android:layout_width="128dp"
    	    android:layout_height="128dp"
    	    android:layout_marginTop="10dp"/>

JAVA 代码：

package com.example.gesturesave;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.DialogInterface.OnClickListener;
import android.gesture.Gesture;
import android.gesture.GestureLibraries;
import android.gesture.GestureLibrary;
import android.gesture.GestureOverlayView;
import android.gesture.GestureOverlayView.OnGesturePerformedListener;
import android.graphics.Bitmap;
import android.graphics.Color;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;

@SuppressLint("SdCardPath")
public class MainActivity extends Activity {

	EditText editText;
	GestureOverlayView gestureOverlayView;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		editText = (EditText) findViewById(R.id.gesture_name);
		gestureOverlayView = (GestureOverlayView) findViewById(R.id.gesture);
		gestureOverlayView.setGestureColor(Color.RED);
		gestureOverlayView.setGestureStrokeWidth(4);

		gestureOverlayView
				.addOnGesturePerformedListener(new OnGesturePerformedListener() {

					@Override
					public void onGesturePerformed(GestureOverlayView arg0,
							final Gesture gesture) {
						View saveDialogView = getLayoutInflater().inflate(
								R.layout.save, null);

						ImageView imageView = (ImageView) saveDialogView
								.findViewById(R.id.show);
						final EditText gestureName = (EditText) saveDialogView
								.findViewById(R.id.gesture_name);
						Bitmap bitmap = gesture.toBitmap(128, 128, 0,
								0xffff0000);
						imageView.setImageBitmap(bitmap);

						new AlertDialog.Builder(MainActivity.this)
								.setView(saveDialogView)
								.setPositiveButton("保存", new OnClickListener() {

									@Override
									public void onClick(DialogInterface dialog,
											int which) {
										// 核心代码
										//获取指定文件对应的手势库
										GestureLibrary gestureLibrary = GestureLibraries
												.fromFile("/sdcard/mygesture");
										//手势库
										gestureLibrary.addGesture(gestureName
												.getText().toString(), gesture);
										// 保存手势库
										Toast.makeText(MainActivity.this,
												""+gestureLibrary.save(), Toast.LENGTH_SHORT)
												.show();
//										MainActivity.this.startActivity(new Intent(MainActivity.this, MainActivityLoad.class));
									}
								}).setNegativeButton("取消", null).show();
					}
				});
	}

}

这样就可以向手机内部写入一个手势。手势是一个文件，手势是不能通过数据库的形式存储的。

二、识别手势

main.xml：

    <android.gesture.GestureOverlayView
        android:id="@+id/gesture"
        android:layout_width="match_parent"
        android:layout_height="match_parent" >
    </android.gesture.GestureOverlayView>

JAVA代码：

package com.example.gesturesave;

import java.util.ArrayList;

import android.os.Bundle;
import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.AlertDialog;
import android.gesture.Gesture;
import android.gesture.GestureLibraries;
import android.gesture.GestureLibrary;
import android.gesture.GestureOverlayView;
import android.gesture.Prediction;
import android.gesture.GestureOverlayView.OnGesturePerformedListener;
import android.view.Menu;
import android.widget.ArrayAdapter;
import android.widget.Toast;

@SuppressLint("SdCardPath")
public class MainActivityLoad extends Activity {

	GestureOverlayView gestureOverlayView;
	GestureLibrary gestureLibrary;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);

		gestureLibrary = GestureLibraries.fromFile("/sdcard/mygesture");
		if (gestureLibrary.load()) {
			Toast.makeText(this, "加载成功", 8000).show();
		} else {
			Toast.makeText(this, "加载失败", 8000).show();
		}

		gestureOverlayView = (GestureOverlayView) findViewById(R.id.gesture);
		gestureOverlayView
				.addOnGesturePerformedListener(new OnGesturePerformedListener() {

					@Override
					public void onGesturePerformed(
							GestureOverlayView overlayView, Gesture gesture) {

						ArrayList<Prediction> predictions = gestureLibrary
								.recognize(gesture);
						ArrayList<String> result = new ArrayList<String>();

						for (Prediction pred : predictions) {
							if (pred.score > 2.0) {
								result.add(" 与" + pred.name + "相似度为"
										+ pred.score);
							}
							if (result.size() > 0) {
								ArrayAdapter adapter = new ArrayAdapter(
										MainActivityLoad.this,
										android.R.layout.simple_dropdown_item_1line,
										result.toArray());
								new AlertDialog.Builder(MainActivityLoad.this).
								setAdapter(adapter, null)
								.setPositiveButton("保存", null).show();
							}else{
								Toast.makeText(MainActivityLoad.this, "没有找到匹配的手势", 8000).show();
							}
						}
					}
				});
	}

}

当然，这里面用到了一些需要得到访问权限的东西，所以还需要向manifest文件中添加一些权限。

<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

这样你就可以增加和识别手势了。