本文实例为大家分享了android模拟实现航拍遥控的具体代码，供大家参考，具体内容如下
由于最近做一个航拍项目，手机端模拟遥控，控制无人机，之前在网上这方面的知识比较少，所有就贴出来demo供大家参考,废话少说，先贴图
左右两个点，在圈内活动，一个是控制油门，一个是控制方向，放手后会返回中心点，这些在游戏场景中经常看到，比如射击类的游戏，这里自定义view，继承ImageView，难点就在手指控制这部分，以下是源码。
package com.remotecontrol;
import android.annotation.TargetApi;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Point;
import android.graphics.Rect;
import android.os.Build;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.view.MotionEvent;
import android.view.WindowManager;
import android.widget.ImageView;
/**
* Created by qingyuan on 2016/5/20.
* 自定义view 模拟遥控器
*/
public class RemoteControl extends ImageView {
public final String TAG="RemoteControl";
public RemoteControl(Context context) {
super(context);
InitData( context);
}
public RemoteControl(Context context, AttributeSet attrs) {
super(context, attrs);
InitData( context);
}
public RemoteControl(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
InitData( context);
}
@TargetApi(Build.VERSION_CODES.LOLLIPOP)
public RemoteControl(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
InitData( context);
}
DisplayMetrics dm = new DisplayMetrics();
WindowManager manager;
//屏幕的宽跟高
int mDisplayWidth;
int mDisplayWidth_2;//屏幕宽的1/2
int mDisplayWidth_4;//屏幕宽的1/4
int mDisplayWidth_43;//屏幕宽的3/4
int mDisplayHeight;
int mDisplayHeight_2;//屏幕高的1/2
int mDisplayHeight_4;//屏幕高的1/4
int mDisplayHeight_43;//屏幕高的3/4
Point leftCenter;//左边中点的坐标
Point rightCenter;//右边中点的坐标
/********************右边的底图**************************/
Bitmap btm_bg;
Rect rectSrc_bg;
Rect rectDst_bg;
/********************左边的底图**************************/
Bitmap btm_bar;
Rect rectSrc_bar;
Rect rectDst_bar;
/********************左边的圆点**************************/
Bitmap btm_circle_left;
MyPoint leftPoint;
double leftDistance;//距离中心点的距离
double leftAngle;//atan2的角度值
int leftCircle_2;//圆的一半
/********************右边的圆点**************************/
Bitmap btm_circle_right;
MyPoint rightPoint;
double rightDistance;//距离中心点的距离
double rightAngle;//atan2的角度值
int rightCircle_2;//圆的一半
int stopRadius;//圆的半径,左右的半径是一样的
Matrix matrix;//矩阵，同过改变矩阵来改变bitmap的位置
final double degToRad = Math.PI/180.0;
final double radToDeg = 180.0/Math.PI;
public void InitData(Context context)
{
manager = (WindowManager) context
.getSystemService(Context.WINDOW_SERVICE);
manager.getDefaultDisplay().getMetrics(dm);
mDisplayWidth = dm.widthPixels;
mDisplayHeight = dm.heightPixels;
mDisplayWidth_2=mDisplayWidth/2;//屏幕宽的1/2
mDisplayWidth_4=mDisplayWidth/4;//屏幕宽的1/4
mDisplayWidth_43=mDisplayWidth*3/4;//屏幕宽的3/4
mDisplayHeight_2=mDisplayHeight/2;//屏幕高的1/2
mDisplayHeight_4=mDisplayHeight/4;//屏幕高的1/4
mDisplayHeight_43=mDisplayHeight*3/4;//屏幕高的3/4
btm_bg= BitmapFactory.decodeResource(context.getResources(),R.drawable.control_bg);
btm_circle_left= BitmapFactory.decodeResource(context.getResources(),R.drawable.records);
btm_circle_right= BitmapFactory.decodeResource(context.getResources(),R.drawable.help);
btm_bar= BitmapFactory.decodeResource(context.getResources(),R.drawable.shift_bar_bg);
matrix = new Matrix();
float scaleSize= (float) (mDisplayHeight*1.0/btm_bg.getWidth()*0.65f);//缩放为屏幕的0.65
matrix.postScale(scaleSize,scaleSize);
btm_bg = Bitmap.createBitmap(btm_bg,0,0,btm_bg.getWidth(),btm_bg.getHeight(),matrix,true);
btm_bar = Bitmap.createBitmap(btm_bar,0,0,btm_bar.getWidth(),btm_bar.getHeight(),matrix,true);
btm_circle_left = Bitmap.createBitmap(btm_circle_left,0,0,btm_circle_left.getWidth(),btm_circle_left.getHeight(),matrix,true);
btm_circle_right = Bitmap.createBitmap(btm_circle_right,0,0,btm_circle_right.getWidth(),btm_circle_right.getHeight(),matrix,true);
leftCircle_2=btm_circle_left.getWidth()/2;
rightCircle_2=btm_circle_right.getWidth()/2;
//左边中心点的位置设为
leftCenter=new Point();
leftCenter.set(mDisplayWidth_4,mDisplayHeight_2);
//右边中心点的位置设为
rightCenter=new Point();
rightCenter.set(mDisplayWidth_43,mDisplayHeight_2);
/***********************左边的地图位置***************************/
rectSrc_bar=new Rect(0,0,btm_bar.getWidth(),btm_bar.getHeight());
rectDst_bar=new Rect(
leftCenter.x-btm_bg.getWidth()/2,
leftCenter.y-btm_bg.getHeight()/2,
leftCenter.x+btm_bg.getWidth()/2,
leftCenter.y+btm_bg.getHeight()/2
);
/***********************左边的圆点位置***************************/
leftPoint=new MyPoint(leftCenter.x, leftCenter.y);
/***********************右边的圆底图位置***************************/
rectSrc_bg=new Rect(0,0,btm_bg.getWidth(),btm_bg.getHeight());
rectDst_bg=new Rect(
rightCenter.x-btm_bar.getWidth()/2,
rightCenter.y-btm_bar.getHeight()/2,
rightCenter.x+btm_bar.getWidth()/2,
rightCenter.y+btm_bar.getHeight()/2
);
/***********************右边边的圆点位置***************************/
rightPoint=new MyPoint(rightCenter.x,rightCenter.y);
//半径为底图的一半，这里决定了可移动圆的大小
stopRadius=btm_bg.getWidth()/2;
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawBitmap(btm_bg,rectSrc_bg,rectDst_bg,null);
canvas.drawBitmap(btm_bar,rectSrc_bar,rectDst_bar,null);
//更新的左中心点的位置
matrix.reset();
matrix.postTranslate(leftPoint.x-leftCircle_2,leftPoint.y-leftCircle_2);
canvas.drawBitmap(btm_circle_left,matrix,null);
//更新的右中心点的位置
matrix.reset();
matrix.postTranslate(rightPoint.x-rightCircle_2,rightPoint.y-rightCircle_2);
canvas.drawBitmap(btm_circle_right,matrix,null);
}
@TargetApi(Build.VERSION_CODES.ECLAIR)
@Override
public boolean onTouchEvent(MotionEvent event) {
float x;
float y;
double distance;//圆点离中心点的距离
double angle;//圆点tan2的角度
float x2;
float y2;
double angle2;
double distance2;
switch (MotionEvent.ACTION_MASK & event.getAction())
{
case MotionEvent.ACTION_DOWN:
//判断第一个手指按下的位置所在的区域
if(Math.abs(event.getX()-rightPoint.x)<btm_circle_right.getWidth()
&& Math.abs(event.getY()-rightPoint.y)<btm_circle_right.getHeight())
{
rightPoint.setPointerIndex(0);
rightPoint.setCanMove(true);
}
else if(Math.abs(event.getX()-leftPoint.x)<btm_circle_left.getWidth()
&& Math.abs(event.getY()-leftPoint.y)<btm_circle_left.getHeight())
{
leftPoint.setPointerIndex(0);
leftPoint.setCanMove(true);
}
break;
case MotionEvent.ACTION_POINTER_UP:
//获取离开手指的id
int pointerId = (event.getAction()&MotionEvent.ACTION_POINTER_ID_MASK)>>> MotionEvent.ACTION_POINTER_ID_SHIFT;
//根据手指离开的id判断是开了的是哪个移动的点
if(rightPoint.isCanMove() && rightPoint.getPointerIndex()==pointerId){
rightPoint.setCanMove(false);
//手指离开让圆点返回中心点
rightPoint.x=rightCenter.x;
rightPoint.y=rightCenter.y;
rightPoint.setPointerIndex(-1);
}
if(leftPoint.isCanMove() &&leftPoint.getPointerIndex()==pointerId)
{
leftPoint.setCanMove(false);
leftPoint.x=leftCenter.x;
leftPoint.y=rightCenter.y;
leftPoint.setPointerIndex(-1);
}
break;
case MotionEvent.ACTION_UP:
//全部手指离开之后
rightPoint.setCanMove(false);
rightPoint.x=rightCenter.x;
rightPoint.y=rightCenter.y;
rightPoint.setPointerIndex(0);
leftPoint.setCanMove(false);
leftPoint.x=leftCenter.x;
leftPoint.y=leftCenter.y;
leftPoint.setPointerIndex(0);
break;
case MotionEvent.ACTION_POINTER_DOWN:
//获取第二根手指的id
pointerId = (event.getAction()&MotionEvent.ACTION_POINTER_ID_MASK)>>> MotionEvent.ACTION_POINTER_ID_SHIFT;
//第二根手指按下
if(!rightPoint.isCanMove() && Math.abs(event.getX(pointerId)-rightPoint.x)<btm_circle_right.getWidth()
&& Math.abs(event.getY(pointerId)-rightPoint.y)<btm_circle_right.getHeight())
{
rightPoint.setPointerIndex(pointerId);
rightPoint.setCanMove(true);
}else if(!leftPoint.isCanMove() && Math.abs(event.getX(pointerId)-leftPoint.x)<btm_circle_left.getWidth()
&& Math.abs(event.getY(pointerId)-leftPoint.y)<btm_circle_left.getHeight())
{
leftPoint.setPointerIndex(pointerId);
leftPoint.setCanMove(true);
}
break;
case MotionEvent.ACTION_MOVE:
//如果是单指移动
if(event.getPointerCount()==1) {
if (rightPoint.isCanMove()) {
x=event.getX(0)-rightCenter.x;
y=event.getY(0)-rightCenter.y;
//计算角度，atan2的用法自己百度咯
angle = (Math.atan2( x, y )*radToDeg)-90;
distance = Math.sqrt((x*x)+(y*y));
//判断是不是超出了规定的半径长度
if( distance >= stopRadius ) {
distance = stopRadius;
double radAngle = angle*degToRad;
rightPoint.x = (int) (distance*Math.cos(radAngle))+rightCenter.x;
rightPoint.y = (int) (-distance*Math.sin(radAngle))+rightCenter.y;
}
else
{
rightPoint.x= (int) event.getX(0);
rightPoint.y = (int)event.getY(0);
}
rightDistance=distance;
rightAngle=angle;
}
else if(leftPoint.isCanMove())
{
x=event.getX(0)-leftCenter.x;
y=event.getY(0)-leftCenter.y;
angle = (Math.atan2( x, y )*radToDeg)-90;
distance = Math.sqrt((x*x)+(y*y));
if( distance >= stopRadius ) {
distance = stopRadius;
double radAngle = angle*degToRad;
leftPoint.x = (int) (distance*Math.cos(radAngle))+leftCenter.x;
leftPoint.y = (int) (-distance*Math.sin(radAngle))+leftCenter.y;
}
else
{
leftPoint.x = (int) event.getX(0);
leftPoint.y = (int) event.getY(0);
}
}
}
else
{ //双指移动
if (rightPoint.isCanMove() && rightPoint.getPointerIndex()!=-1 && rightPoint.getPointerIndex()<event.getPointerCount() ) {
x=event.getX(rightPoint.getPointerIndex())-rightCenter.x;
y=event.getY(rightPoint.getPointerIndex())-rightCenter.y;
angle = (Math.atan2( x, y )*radToDeg)-90;
distance = Math.sqrt((x*x)+(y*y));
if( distance >= stopRadius ) {
distance = stopRadius;
double radAngle = angle*degToRad;
rightPoint.x = (int) (distance*Math.cos(radAngle))+rightCenter.x;
rightPoint.y = (int) (-distance*Math.sin(radAngle))+rightCenter.y;
}
else
{
rightPoint.x = (int) event.getX(rightPoint.getPointerIndex());
rightPoint.y = (int) event.getY(rightPoint.getPointerIndex());
}
rightDistance=distance;
rightAngle=angle;
}
if(leftPoint.isCanMove() && leftPoint.getPointerIndex()!=-1 && leftPoint.getPointerIndex()<event.getPointerCount())
{
x2=event.getX(leftPoint.getPointerIndex())-leftCenter.x;
y2=event.getY(leftPoint.getPointerIndex())-leftCenter.y;
angle2 = (Math.atan2( x2, y2 )*radToDeg)-90;
distance2 = Math.sqrt((x2*x2)+(y2*y2));
if( distance2 >= stopRadius ) {
distance2 = stopRadius;
double radAngle = angle2*degToRad;
leftPoint.x = (int) (distance2*Math.cos(radAngle))+leftCenter.x;
leftPoint.y = (int) (-distance2*Math.sin(radAngle))+leftCenter.y;
}
else
{
leftPoint.x = (int) event.getX(leftPoint.getPointerIndex());
leftPoint.y = (int) event.getY(leftPoint.getPointerIndex());
}
leftDistance=distance2;
leftAngle=angle2;
}
}
break;
}
invalidate();
return true;
}
public double getRightDistance() {
return rightDistance;
}
public double getRightAngle() {
return rightAngle;
}
public double getLeftAngle() {
return leftAngle;
}
public double getLeftDistance() {
return leftDistance;
}
/**
* 自定义坐标点，添加了两个属性
*/
public class MyPoint extends Point{
//手指的index
private int pointerIndex=-1;
//是否能移动
private boolean isCanMove;
public boolean isCanMove() {
return isCanMove;
}
public void setCanMove(boolean canMove) {
isCanMove = canMove;
}
public MyPoint(int x, int y) {
super(x, y);
}
public int getPointerIndex() {
return pointerIndex;
}
public void setPointerIndex(int pointerIndex) {
this.pointerIndex = pointerIndex;
}
}
}
在我的真正项目中对内存性能要求比较高，所有我并没有直接用继承ImageView，而是使用了SurfaceView,双缓冲，单独线程刷新画面，还有局部刷新，基本上跟上面的差不多，只是将onDraw（）里面的刷新代码放到SurfaceView中，网上也有很多SurfaceView使用的例子，稍微借鉴一下就能转过来。
