丰富方法实现,添加打印图片时的逻辑判断及排版处理

app/src/main/java/com/miya/hardware/PrintActivity.java

@@ -13,6 +13,7 @@ import android.widget.TextView;
 
 import com.miya.print.PrinterManager;
 import com.miya.print.PrinterStatusEnum;
+import com.miya.print.utils.BitmapUtils;
 
 public class PrintActivity extends Activity implements View.OnClickListener {
 
@@ -172,7 +173,7 @@ public class PrintActivity extends Activity implements View.OnClickListener {
                 break;
             case R.id.btnPrintImg:
                 if (PrinterManager.getInstance().isConnected()) {
-                    Bitmap bm = BitmapFactory.decodeResource(getResources(), R.drawable.logo_demo);
+                    Bitmap bm = BitmapUtils.scaleBitmap(BitmapFactory.decodeResource(getResources(), R.drawable.logo_demo), 240, 0);
                     try {
                         PrinterManager.getInstance().getPrinter().printImage(-1, bm, false);
                     } catch (Exception ex) {

app/src/main/res/layout/activity_print.xml

@@ -146,7 +146,8 @@
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:layout_weight="1"
-                android:text="设置成58mm打印纸" />
+                android:text="设置成58mm打印纸"
+                android:visibility="gone" />
         </TableRow>
 
         <TableRow>
@@ -156,7 +157,8 @@
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:layout_weight="1"
-                android:text="设置成80mm打印纸" />
+                android:text="设置成80mm打印纸"
+                android:visibility="gone" />
         </TableRow>
 
         <TableRow>

print/src/main/java/com/miya/print/ChuangjiePrinter.java

@@ -11,6 +11,7 @@ import android.hardware.usb.UsbManager;
 import android.text.TextUtils;
 import android.util.Log;
 
+import com.miya.print.utils.BitmapUtils;
 import com.miya.print.utils.D;
 import com.miya.print.utils.ImageUtils;
 import com.printsdk.cmd.PrintCmd;
@@ -49,6 +50,11 @@ public class ChuangjiePrinter extends BasePrinter {
      */
     int align = 0;
 
+    /**
+     * 80mm打印纸允许打印的最大图片的宽度,此为经验值
+     */
+    final static int MAX_IMG_WIDTH_80MM = 570;
+
     @Override
     public boolean init(Context context) {
         this.context = context;
@@ -260,8 +266,24 @@ public class ChuangjiePrinter extends BasePrinter {
 
     @Override
     public int printImage(int align, Bitmap bm, boolean isFeed) {
+        if (bm == null) {
+            return PrinterStatusEnum.CODE_FAILED.getStatus();
+        }
         int ret = setAlign(align);
-        ret = printQrcodeBitmap(bm);
+        Bitmap actualBm = null;
+        if (bm.getWidth() > MAX_IMG_WIDTH_80MM) {
+            actualBm = BitmapUtils.scaleBitmap(bm, MAX_IMG_WIDTH_80MM, 0);
+            ret = printQrcodeBitmap(actualBm);
+        } else {
+            //如果是居中打印，则拼接白色左边距
+            if (align == 1) {
+                actualBm = BitmapUtils.addWhiteLeftMargin(bm, (MAX_IMG_WIDTH_80MM - bm.getWidth()) / 2);
+                ret = printQrcodeBitmap(actualBm);
+            }
+        }
+        if (actualBm != null) {
+            actualBm.recycle();
+        }
         if (isFeed) {
             feedPaper();
         }
@@ -271,7 +293,16 @@ public class ChuangjiePrinter extends BasePrinter {
     @Override
     public int printQrcode(int align, String content, boolean isFeed) {
         int ret = setAlign(align);
-        ret = printQrcode(content, 0, 6, 1);
+        if (this.align == 0) {
+            //居左打印
+            ret = printQrcode(content, 0, 6, 1);
+        } else if (this.align == 1) {
+            //居中打印
+//            ret = printQrcode()
+        } else if (this.align == 2) {
+            //居右
+//            ret = printQrcode()
+        }
         if (isFeed) {
             ret = feedPaper();
         }

print/src/main/java/com/miya/print/utils/BitmapUtils.java

+package com.miya.print.utils;
+
+import android.graphics.Bitmap;
+import android.graphics.Canvas;
+import android.graphics.Matrix;
+import android.graphics.Paint;
+import android.graphics.Rect;
+import android.util.Log;
+
+/**
+ * bitmap处理工具类
+ */
+public class BitmapUtils {
+
+    /**
+     * 按指定宽高缩放源bitmap
+     *
+     * @param origin 源bitmap
+     * @param width  指定宽度，传0代表按height的比例进行缩放，比例计算公式：scale = origin.getHeight()/height
+     * @param height 指定高度，传0代表按width的比例进行缩放，比例计算公式：scale = origin.getWidth()/width
+     * @return width，height都传0代表不缩放，外部调用者注意bitmap回收
+     */
+    public static Bitmap scaleBitmap(Bitmap origin, int width, int height) {
+        if (origin == null) {
+            return null;
+        }
+        int widthOrigin = origin.getWidth();
+        int heightOrigin = origin.getHeight();
+        Matrix matrix = new Matrix();
+        float scaleX = (float) width / (float) widthOrigin;
+        float scaleY = (float) height / (float) heightOrigin;
+        if (width == 0) {
+            scaleX = scaleY;
+        }
+        if (height == 0) {
+            scaleY = scaleX;
+        }
+        if ((width == 0 && height == 0) || width < 0 || height < 0) {
+            //返回原图片
+            return origin;
+        }
+        matrix.preScale(scaleX, scaleY);
+        Bitmap newBM = Bitmap.createBitmap(origin, 0, 0, widthOrigin, heightOrigin, matrix, false);
+        if (newBM.equals(origin)) {
+            return newBM;
+        }
+        origin.recycle();
+        return newBM;
+    }
+
+    /**
+     * 给源bitmap添加白色左边距，用于打印对齐
+     *
+     * @param origin 源bitmap
+     * @param width  指定左边距宽度
+     * @return
+     */
+    public static Bitmap addWhiteLeftMargin(Bitmap origin, int width) {
+        if (origin == null) {
+            return null;
+        }
+        if (width <= 0) {
+            return origin;
+        }
+        Bitmap newBm = Bitmap.createBitmap(width + origin.getWidth(), origin.getHeight(), origin.getConfig());
+        Canvas canvas = new Canvas(newBm);
+        //绘制左边白色边距
+        canvas.drawColor(0xffffffff);
+        canvas.drawBitmap(origin, width, 0, null);
+        return newBm;
+    }
+}