还是我，不过换了blog。
嗯，本人偷懒，在原来的项目上改了点儿东西。简洁了许多。
关于配置和一些用法，传送门：
我在摇杆上投入的心思也不算很多，一天左右，看了看官方的API文档，悲剧的发现了一个问题。
我们要监听摇杆啊？对不对，他摇杆摇了，我得要有个事件通知我。然后再实现自己想要的功能。
我做了一个小测试：
Touchpad touchpad = new Touchpad(0f, skin); touchpad.setPosition(0, 0); touchpad.setSize(300, 300); touchpad.addListener(new InputListener(){ @Override public boolean touchDown(InputEvent event, float x, float y, int pointer, int button) { // TODO Auto-generated method stub Gdx.app.log("DOWN", x+":"+y); return super.touchDown(event, x, y, pointer, button); } @Override public void touchUp(InputEvent event, float x, float y, int pointer, int button) { // TODO Auto-generated method stub Gdx.app.log("UP", x+":"+y); super.touchUp(event, x, y, pointer, button); } @Override public void touchDragged(InputEvent event, float x, float y, int pointer) { // TODO Auto-generated method stub Gdx.app.log("DRAG", x+":"+y); super.touchDragged(event, x, y, pointer); } }); 我们会惊奇的发现。控制台输出的内容只有 DOWN，坐标值。
我们想象中的UP ，和 DRAG 根本没实现。到底是不是我做错了什么~好吧，我承认我懒，没有深入研究下去。做了一个取巧的方法。
自己写了一个Touchpad，当然，继承于libgdx的Touchpad，代码如下
package com.cavacn.game;import com.badlogic.gdx.Gdx;import com.badlogic.gdx.graphics.g2d.SpriteBatch;import com.badlogic.gdx.scenes.scene2d.ui.Skin;import com.badlogic.gdx.scenes.scene2d.ui.Touchpad;public class cavaTouchpad extends Touchpad { private cavaTouchEvent event; public void addCavaListenner(cavaTouchEvent listener){ event = listener; } public void draw(SpriteBatch batch, float parentAlpha) { if(event!=null){ if(this.isTouched()){ event.handle(); } } // TODO Auto-generated method stub super.draw(batch, parentAlpha); } public cavaTouchpad(float deadzoneRadius, Skin skin, String styleName) { super(deadzoneRadius, skin, styleName); // TODO Auto-generated constructor stub } public cavaTouchpad(float deadzoneRadius, Skin skin) { super(deadzoneRadius, skin); // TODO Auto-generated constructor stub } public cavaTouchpad(float deadzoneRadius, TouchpadStyle style) { super(deadzoneRadius, style); // TODO Auto-generated constructor stub } } 当然，在这之前我们需要写一个类似委托的东西
package com.cavacn.game;import com.badlogic.gdx.scenes.scene2d.ui.Touchpad;public class cavaTouchEvent { private Touchpad touchpad; public cavaTouchEvent(Touchpad touchpad){ this.touchpad = touchpad; } public boolean handle() { if(this.touchpad==null){ return false;} cavaTouchDragged(this.touchpad.getKnobPercentX(),this.touchpad.getKnobPercentY()); return true; } public void cavaTouchDragged(float x,float y){ } } 我就这样，自己添加了两个类。然后场景实现代码如下：
package com.cavacn.game;import com.badlogic.gdx.ApplicationListener;import com.badlogic.gdx.Gdx;import com.badlogic.gdx.graphics.GL10;import com.badlogic.gdx.graphics.OrthographicCamera;import com.badlogic.gdx.graphics.Texture;import com.badlogic.gdx.graphics.Texture.TextureFilter;import com.badlogic.gdx.graphics.g2d.Sprite;import com.badlogic.gdx.graphics.g2d.SpriteBatch;import com.badlogic.gdx.graphics.g2d.TextureRegion;import com.badlogic.gdx.scenes.scene2d.InputEvent;import com.badlogic.gdx.scenes.scene2d.InputListener;import com.badlogic.gdx.scenes.scene2d.Stage;import com.badlogic.gdx.scenes.scene2d.ui.Skin;import com.badlogic.gdx.scenes.scene2d.ui.Touchpad;public class cavaGame implements ApplicationListener { private Stage stage; @Override public void create() { float width = 1280f; float height = 720f; stage = new Stage(width,height,false); Skin skin = new Skin(Gdx.files.internal("ui/uiskin.json")); /*Touchpad touchpad = new Touchpad(0f, skin); touchpad.setPosition(0, 0); touchpad.setSize(300, 300);*/ cavaTouchpad touchpad = new cavaTouchpad(0f, skin); touchpad.setPosition(0, 0); touchpad.setSize(400, 400); touchpad.addCavaListenner(new cavaTouchEvent(touchpad){ @Override public void cavaTouchDragged(float x,float y) { // TODO Auto-generated method stub Gdx.app.log("CAVACN", x+":"+y); } }); /*touchpad.addListener(new InputListener(){ @Override public boolean touchDown(InputEvent event, float x, float y, int pointer, int button) { // TODO Auto-generated method stub Gdx.app.log("DOWN", x+":"+y); return super.touchDown(event, x, y, pointer, button); } @Override public void touchUp(InputEvent event, float x, float y, int pointer, int button) { // TODO Auto-generated method stub Gdx.app.log("UP", x+":"+y); super.touchUp(event, x, y, pointer, button); } @Override public void touchDragged(InputEvent event, float x, float y, int pointer) { // TODO Auto-generated method stub Gdx.app.log("DRAG", x+":"+y); super.touchDragged(event, x, y, pointer); } });*/ stage.addActor(touchpad); } @Override public void dispose() { stage.dispose(); } @Override public void render() { Gdx.input.setInputProcessor(stage); Gdx.gl.glClearColor(0, 0, 0, 0); Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT); stage.act(); stage.draw(); } @Override public void resize(int width, int height) { } @Override public void pause() { } @Override public void resume() { }} 非常简单的一个Demo。不过总算我们可以在控制台当中看到 CAVACN 坐标值
特别声明，我这里出来的结果 x 是 the x-position of the knob as a percentage from the center of the touchpad to the edge of the circular movement area.
y 是 the y-position of the knob as a percentage from the center of the touchpad to the edge of the circular movement area.
从字面上理解是，x和y都是由中心点为原点的正负百分比。
到了文章的最后，我把demo发给大家，传送门：