Android App运行核心，Handler,Looper,Message

Posted 2022-05-27 QXXXD

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目标

在手机屏幕上显示指定的区域

两种方法

在已存在的图片上, 绘制矩形, 查看图片
在全屏透明悬浮窗上直接画矩形

已有图片绘制矩形

读取图片

let imgFilepath = files.path("./chess.png");
let img = images.read(imgFilepath);

设置绘制区域

let rect = 
  left: 52,
  top: 20,
  right: 138,
  bottom: 96,
;

设置画笔属性: 绿色, 空心

let paint = new Paint();
paint.setStrokeWidth(9);
paint.setColor(colors.parseColor("#00ff00"));
paint.setStyle(Paint.Style.STROKE);

在图片上画矩形

var canvas = new Canvas(img);
canvas.drawRect(left, top, right, bottom, paint);

把canvas的数据转成图片

var image = canvas.toImage();
let filePath = "/sdcard/脚本/showRect.png";
files.createWithDirs(filePath);
images.save(image, filePath);

回收资源

image.recycle();
img.recycle();

查看图片

app.viewFile(filePath);

在全屏透明悬浮窗上直接画矩形, 圆形, 文字

[外链图片转存失败,源站可能有防盗链机制,建议将图片保存下来直接上传(img-8wZJvH7V-1653557247873)(https://p3-juejin.byteimg.com/tos-cn-i-k3u1fbpfcp/97542b35b48c4f8bae83178b5e2a29ce~tplv-k3u1fbpfcp-zoom-in-crop-mark:1956:0:0:0.image)]

使用示例

let Board = require("./board");
let board = new Board();
setTimeout(() => 
  board.drawText(
    x: 100,
    y: 200,
    text: "Hello World",
  );
  sleep(1000);
  board.setPaintColor("#00ff00");
  board.drawCircle(
    x: 200,
    y: 400,
    radius: 100,
  );
  sleep(1000);
  board.setPaintColor("#0000ff");
  board.drawRect(
    left: 400,
    top: 300,
    right: 600,
    bottom: 500,
  );
, 1000);

把绘制方法封装成了一个模块Board

检查悬浮窗权限

function ensureFloatyPermission() 
  if (floaty.checkPermission()) 
    return true;
  
  toastLog("请授予悬浮窗权限");
  app.startActivity(
    action: "android.settings.action.MANAGE_OVERLAY_PERMISSION",
    data: "package:" + context.packageName,
  );
  throw new Error("请授予悬浮窗权限");

创建悬浮窗

function createFloatyWindow() 
  let floatyWindow = floaty.rawWindow(
    <frame bg="#88ff0000">
      <canvas id="board" w="*" h="*" />
    </frame>
  );
  ui.run(function () 
    floatyWindow.setSize(-1, -1);
    floatyWindow.setPosition(0, 0);
    let touchable = false;
    floatyWindow.setTouchable(touchable);
  );
  return floatyWindow;

创建画笔

function createPaint() 
  paint = new Paint();
  paint.setStyle(Paint.Style.FILL);
  paint.setTextSize(100);
  return paint;

设置画板draw事件

board.on("draw", (canvas) => 
  canvas.drawColor(android.graphics.Color.TRANSPARENT, android.graphics.PorterDuff.Mode.CLEAR);
  canvas.drawBitmap(fullScreenBitmap, 0, 0, paint);
);

绘制矩形

Board.prototype.drawRect = function (rect) 
  ensureFullScreenCanvas(fullScreenCanvas);
  ensureRectType(rect);
  fullScreenCanvas.drawRect(rect.left, rect.top, rect.right, rect.bottom, paint);
;

所有代码能拆的都拆了, 每个功能函数的行数都很少,

见名知意, 满分10分, 我打9分