android实现类似扫描二维码的界面
从zxing的项目里提取出来的，不过省去了配置一堆xml的麻烦
import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.LinearGradient;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Shader;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.view.View;
public final class ViewfinderView extends View {
private static final long ANIMATION_DELAY = 15L;
private static final int POINT_SIZE = 20;
private static final int CORNER_RECT_WIDTH = 8; //扫描区边角的宽
private static final int CORNER_RECT_HEIGHT = 40; //扫描区边角的高
private static final int SCANNER_LINE_MOVE_DISTANCE = 6; //扫描线移动距离
private static final int SCANNER_LINE_HEIGHT = 10; //扫描线宽度
private Paint paint;
private int maskColor = Color.parseColor("#60000000");;
private int frameColor = Color.parseColor("#7F1FB3E2");
private int laserColor = Color.parseColor("#FF1FB3E2");
private int cornerColor = Color.parseColor("#FF1FB3E2");
public int scannerStart = 0;
public int scannerEnd = 0;
private int frameWidth = 0;
private int frameHeight = 0;
private int screenWidth;
private int screenHeight;
private Rect frame;
public enum LaserStyle{
NONE(0),LINE(1),GRID(2);
private int mValue;
LaserStyle(int value){
mValue = value;
}
private static LaserStyle getFromInt(int value){
for(LaserStyle style : LaserStyle.values()){
if(style.mValue == value){
return style;
}
}
return LaserStyle.LINE;
}
}
private LaserStyle laserStyle = LaserStyle.LINE;;
private int gridColumn = 20;
private int gridHeight = 40;
public ViewfinderView(Context context) {
this(context,null);
}
public ViewfinderView(Context context, @Nullable AttributeSet attrs) {
this(context, attrs,0);
}
public ViewfinderView(Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init(context,attrs);
}
private DisplayMetrics getDisplayMetrics(){
return getResources().getDisplayMetrics();
}
private void init(Context context, AttributeSet attrs) {
paint = new Paint(Paint.ANTI_ALIAS_FLAG);
screenWidth = getDisplayMetrics().widthPixels;
screenHeight = getDisplayMetrics().heightPixels;
int size = (int)(Math.min(screenWidth,screenHeight) * 0.625f);
if(frameWidth<=0 || frameWidth > screenWidth){
frameWidth = size;
}
if(frameHeight<=0 || frameHeight > screenHeight){
frameHeight = size/2;
}
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
//扫码框默认居中，支持利用内距偏移扫码框
int leftOffset = (screenWidth - frameWidth) / 2 + getPaddingLeft() - getPaddingRight();
int topOffset = (screenHeight - frameHeight) / 2 + getPaddingTop() - getPaddingBottom() - 100;
frame = new Rect(leftOffset, topOffset, leftOffset + frameWidth, topOffset + frameHeight);
}
@SuppressLint("DrawAllocation")
@Override
public void onDraw(Canvas canvas) {
if (frame == null) {
return;
}
if(scannerStart == 0 || scannerEnd == 0) {
scannerStart = frame.top;
scannerEnd = frame.bottom - SCANNER_LINE_HEIGHT;
}
int width = canvas.getWidth();
int height = canvas.getHeight();
drawExterior(canvas,frame,width,height);
drawLaserScanner(canvas,frame);
drawFrame(canvas, frame);
drawCorner(canvas, frame);
postInvalidateDelayed(ANIMATION_DELAY,
frame.left - POINT_SIZE,
frame.top - POINT_SIZE,
frame.right + POINT_SIZE,
frame.bottom + POINT_SIZE);
}
private void drawExterior(Canvas canvas, Rect frame, int width, int height) {
paint.setColor(maskColor);
canvas.drawRect(0, 0, width, frame.top, paint);
canvas.drawRect(0, frame.top, frame.left, frame.bottom + 1, paint);
canvas.drawRect(frame.right + 1, frame.top, width, frame.bottom + 1, paint);
canvas.drawRect(0, frame.bottom + 1, width, height, paint);
}
private void drawFrame(Canvas canvas, Rect frame) {
paint.setColor(frameColor);
canvas.drawRect(frame.left, frame.top, frame.right + 1, frame.top + 2, paint);
canvas.drawRect(frame.left, frame.top + 2, frame.left + 2, frame.bottom - 1, paint);
canvas.drawRect(frame.right - 1, frame.top, frame.right + 1, frame.bottom - 1, paint);
canvas.drawRect(frame.left, frame.bottom - 1, frame.right + 1, frame.bottom + 1, paint);
}
private void drawCorner(Canvas canvas, Rect frame) {
paint.setColor(cornerColor);
//左上
canvas.drawRect(frame.left, frame.top, frame.left + CORNER_RECT_WIDTH, frame.top + CORNER_RECT_HEIGHT, paint);
canvas.drawRect(frame.left, frame.top, frame.left + CORNER_RECT_HEIGHT, frame.top + CORNER_RECT_WIDTH, paint);
//右上
canvas.drawRect(frame.right - CORNER_RECT_WIDTH, frame.top, frame.right, frame.top + CORNER_RECT_HEIGHT, paint);
canvas.drawRect(frame.right - CORNER_RECT_HEIGHT, frame.top, frame.right, frame.top + CORNER_RECT_WIDTH, paint);
//左下
canvas.drawRect(frame.left, frame.bottom - CORNER_RECT_WIDTH, frame.left + CORNER_RECT_HEIGHT, frame.bottom, paint);
canvas.drawRect(frame.left, frame.bottom - CORNER_RECT_HEIGHT, frame.left + CORNER_RECT_WIDTH, frame.bottom, paint);
//右下
canvas.drawRect(frame.right - CORNER_RECT_WIDTH, frame.bottom - CORNER_RECT_HEIGHT, frame.right, frame.bottom, paint);
canvas.drawRect(frame.right - CORNER_RECT_HEIGHT, frame.bottom - CORNER_RECT_WIDTH, frame.right, frame.bottom, paint);
}
public int shadeColor(int color) {
String hax = Integer.toHexString(color);
String result = "01"+hax.substring(2);
return Integer.valueOf(result, 16);
}
private void drawLineScanner(Canvas canvas,Rect frame){
//线性渐变
LinearGradient linearGradient = new LinearGradient(
frame.left, scannerStart,
frame.left, scannerStart + SCANNER_LINE_HEIGHT,
shadeColor(laserColor),
laserColor,
Shader.TileMode.MIRROR);
paint.setShader(linearGradient);
if(scannerStart <= scannerEnd) {
//椭圆
RectF rectF = new RectF(frame.left + 2 * SCANNER_LINE_HEIGHT, scannerStart, frame.right - 2 * SCANNER_LINE_HEIGHT, scannerStart + SCANNER_LINE_HEIGHT);
canvas.drawOval(rectF, paint);
scannerStart += SCANNER_LINE_MOVE_DISTANCE;
} else {
scannerStart = frame.top;
}
}
private void drawGridScanner(Canvas canvas,Rect frame){
int stroke = 2;
paint.setStrokeWidth(stroke);
//计算Y轴开始位置
int startY = gridHeight > 0 && scannerStart - frame.top > gridHeight ? scannerStart - gridHeight : frame.top;
LinearGradient linearGradient = new LinearGradient(frame.left + frame.width()/2, startY, frame.left + frame.width()/2, scannerStart, new int[]{shadeColor(laserColor), laserColor}, new float[]{0,1f}, LinearGradient.TileMode.CLAMP);
//给画笔设置着色器
paint.setShader(linearGradient);
float wUnit = frame.width() * 1.0f/ gridColumn;
float hUnit = wUnit;
//遍历绘制网格纵线
for (int i = 1; i < gridColumn; i++) {
canvas.drawLine(frame.left + i * wUnit, startY,frame.left + i * wUnit, scannerStart,paint);
}
int height = gridHeight > 0 && scannerStart - frame.top > gridHeight ? gridHeight : scannerStart - frame.top;
//遍历绘制网格横线
for (int i = 0; i <= height/hUnit; i++) {
canvas.drawLine(frame.left, scannerStart - i * hUnit,frame.right, scannerStart - i * hUnit,paint);
}
if(scannerStart